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Posted to commits@marmotta.apache.org by wi...@apache.org on 2013/02/19 13:52:00 UTC

[21/52] [partial] code contribution, initial import of relevant modules of LMF-3.0.0-SNAPSHOT based on revision 4bf944319368 of the default branch at https://code.google.com/p/lmf/

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ClassificationClient.java
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diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ClassificationClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ClassificationClient.java
new file mode 100644
index 0000000..9e6aee6
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+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ClassificationClient.java
@@ -0,0 +1,362 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.model.classification.Classification;
+import at.newmedialab.lmf.client.model.rdf.URI;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import com.google.common.base.Preconditions;
+import com.google.common.io.ByteStreams;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpDelete;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.ContentProducer;
+import org.apache.http.entity.EntityTemplate;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.util.Collection;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * A client supporting access to the LMF Classification Services. Allows creating and removing classifiers as
+ * well as training classifiers with sample data and the classification of textual documents.
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class ClassificationClient {
+
+    private static Logger log = LoggerFactory.getLogger(ClassificationClient.class);
+
+    private static final String URL_CLASSIFICATION_SERVICE = "/classifier";
+
+
+    private ClientConfiguration config;
+
+    public ClassificationClient(ClientConfiguration config) {
+        this.config = config;
+    }
+
+
+    /**
+     * Create a new classifier with the given name. The service will take care of creating the appropriate
+     * configuration entries and work files in the LMF work directory.
+     *
+     * @param name a string identifying the classifier; should only consist of alphanumeric characters (no white spaces)
+     */
+    public boolean createClassifier(String name) throws LMFClientException, IOException {
+        Preconditions.checkArgument(name.matches("^\\p{Alnum}+$"));
+
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpPost post = new HttpPost(config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + name);
+        
+        try {
+
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 403:
+                    log.debug("classifier {} already existed, not creating new",name);
+                    return true;
+                case 200:
+                    log.debug("classifier {} created",name);
+                    return true;
+                default:
+                    log.error("error creating classifier {}: {} {}",new Object[] {name,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    return true;
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            return false;
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Remove the classifier with the given name from the system configuration.
+     *
+     * @param name       a string identifying the classifier; should only consist of alphanumeric characters (no white spaces)
+     * @param removeData also remove all training and model data of this classifier from the file system
+     */
+    public void removeClassifier(String name, boolean removeData) throws LMFClientException, IOException {
+        Preconditions.checkArgument(name.matches("^\\p{Alnum}+$"));
+
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpDelete delete = new HttpDelete(config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + name + (removeData?"?removeData=true":""));
+            
+            try {
+            
+            HttpResponse response = httpClient.execute(delete);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classifier {} deleted", name);
+                    break;
+                case 404:
+                    log.error("classifier {} does not exist, cannot delete", name);
+                    break;
+                default:
+                    log.error("error deleting classifier {}: {} {}",new Object[] {name,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            delete.abort();
+            log.error("could not encode URI parameter",e);
+        } finally {
+            delete.releaseConnection();
+        }
+    }
+
+
+    /**
+     * List all classifiers registered in the classification service.
+     *
+     * @return a collection of Classifier instances representing all registered classifiers
+     */
+    public Collection<String> listClassifiers() throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/list";
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+
+        try {
+            
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classifiers listed successfully");
+                    ObjectMapper mapper = new ObjectMapper();
+                    List<String> result = mapper.readValue(response.getEntity().getContent(),new TypeReference<List<String>>(){});
+                    
+                    return result;
+                default:
+                    log.error("error retrieving list of classifiers: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving list of classifiers: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Add training data to the classifier identified by the given name and for the concept passed as argument. Note
+     * that training data is not immediately taken into account by the classifier. Retraining of the classifier will
+     * take place when a certain threshold of training datasets has been added or when a certain (configurable) time has
+     * passed.
+     *
+     * @param name        a string identifying the classifier; should only consist of alphanumeric characters (no white spaces)
+     * @param concept_uri the URI of the concept which to train with the sample text
+     * @param sampleText  the sample text for the concept
+     */
+    public void trainClassifier(String name, String concept_uri, final String sampleText) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + URLEncoder.encode(name,"utf-8") + "/train?concept=" + URLEncoder.encode(concept_uri,"utf-8");
+
+        HttpPost post = new HttpPost(serviceUrl);
+        post.setHeader("Content-Type", "text/plain");
+        
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(new ByteArrayInputStream(sampleText.getBytes("utf-8")), outstream);
+            }
+        };
+        
+        post.setEntity(new EntityTemplate(cp));
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classifier {} updated successfully",name);
+                    break;
+                default:
+                    log.error("error updating classifier {}: {} {}",new Object[] {name,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating classifier "+name+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Retrain the classifier with the given name immediately. Will read in the training data and create a new
+     * classification model.
+     *
+     * @param name
+     * @throws LMFClientException
+     */
+    public void retrainClassifier(String name) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + URLEncoder.encode(name,"utf-8") + "/retrain";
+
+        HttpPost post = new HttpPost(serviceUrl);
+        
+        try {
+            
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classifier {} retrained successfully",name);
+                    break;
+                default:
+                    log.error("error retraining classifier {}: {} {}",new Object[] {name,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating classifier "+name+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Get classifications from the given classifier for the given text. The classifications will be ordered by
+     * descending probability, so that classifications with higher probability will be first. A classification object
+     * consists of a KiWiUriResource identifying the classified concept and a probability indicating how likely it is
+     * that the text matches the given concept.
+     *
+     * @param classifier a string identifying the classifier; should only consist of alphanumeric characters (no white spaces)
+     * @param text       the text to classify
+     * @return a list of classifications ordered by descending probability
+     */
+    public List<Classification> getAllClassifications(String classifier, final String text) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + classifier+"/classify";
+
+        HttpPost post = new HttpPost(serviceUrl);
+        post.setHeader("Content-Type", "text/plain");
+        
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(new ByteArrayInputStream(text.getBytes("utf-8")), outstream);
+            }
+        };
+        
+        post.setEntity(new EntityTemplate(cp));
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classification {} executed successfully",classifier);
+                    ObjectMapper mapper = new ObjectMapper();
+                    List<Map<String,String>> jsonResult =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<List<Map<String,String>>>(){});
+
+                    List<Classification> result = new LinkedList<Classification>();
+                    for(Map<String,String> entry : jsonResult) {
+                        result.add(new Classification(new URI(entry.get("concept")), Double.parseDouble(entry.get("probability"))));
+                    }
+                    return result;
+                default:
+                    log.error("error executing classifier {}: {} {}",new Object[] {classifier,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error executing classifier "+classifier+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Get classifications from the given classifier for the given text. The classifications will be ordered by
+     * descending probability, so that classifications with higher probability will be first. Only classifications with
+     * a probability higher than the threshold will be considered. A classification object
+     * consists of a KiWiUriResource identifying the classified concept and a probability indicating how likely it is
+     * that the text matches the given concept.
+     *
+     * @param classifier a string identifying the classifier; should only consist of alphanumeric characters (no white spaces)
+     * @param text       the text to classify
+     * @param threshold  the minimum probability of a classification to be considered in the result
+     * @return a list of classifications ordered by descending probability, all having higher probability than threshold
+     */
+    public List<Classification> getAllClassifications(String classifier, final String text, double threshold) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CLASSIFICATION_SERVICE + "/" + classifier+"/classify?threshold="+threshold;
+
+        HttpPost post = new HttpPost(serviceUrl);
+        post.setHeader("Content-Type", "text/plain");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(new ByteArrayInputStream(text.getBytes("utf-8")), outstream);
+            }
+        };
+        post.setEntity(new EntityTemplate(cp));
+        
+        try {
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("classification {} executed successfully",classifier);
+                    ObjectMapper mapper = new ObjectMapper();
+                    List<Map<String,String>> jsonResult =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<List<Map<String,String>>>(){});
+
+                    List<Classification> result = new LinkedList<Classification>();
+                    for(Map<String,String> entry : jsonResult) {
+                        result.add(new Classification(new URI(entry.get("concept")), Double.parseDouble(entry.get("probability"))));
+                    }
+                    return result;
+                default:
+                    log.error("error executing classifier {}: {} {}",new Object[] {classifier,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error executing classifier "+classifier+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ConfigurationClient.java
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diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ConfigurationClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ConfigurationClient.java
new file mode 100644
index 0000000..1d5dd5a
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ConfigurationClient.java
@@ -0,0 +1,264 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.exception.NotFoundException;
+import at.newmedialab.lmf.client.model.config.Configuration;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpDelete;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.ContentProducer;
+import org.apache.http.entity.EntityTemplate;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.net.URLEncoder;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * A client that supports accessing the configuration webservice of the Linked Media Framework. May be used for
+ * retrieving as well as changing properties.
+ *
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class ConfigurationClient {
+    private static Logger log = LoggerFactory.getLogger(ConfigurationClient.class);
+
+    private static final String URL_CONFIG_SERVICE = "/config";
+
+
+    private ClientConfiguration config;
+
+    public ConfigurationClient(ClientConfiguration config) {
+        this.config = config;
+    }
+
+    /**
+     * Return a list of all configuration keys that are currently set in the LMF configuration.
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Set<String> listConfigurationKeys() throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpGet get = new HttpGet(config.getLmfUri() + URL_CONFIG_SERVICE + "/list");
+        get.setHeader("Accept", "application/json");
+
+        try {
+            
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("configurations listed successfully");
+                    ObjectMapper mapper = new ObjectMapper();
+                    Map<String,Map<String,Object>> result =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,Map<String,Object>>>(){});
+                    return result.keySet();
+                default:
+                    log.error("error retrieving list of configuration keys: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving list of configuration keys: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Return a list of all configurations (keys and values) that are currently set in the LMF configuration.
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Set<Configuration> listConfigurations(String prefix) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CONFIG_SERVICE + "/list" + (prefix != null? "?prefix="+ URLEncoder.encode(prefix,"utf-8") : "");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("configurations listed successfully");
+                    ObjectMapper mapper = new ObjectMapper();
+                    Map<String,Map<String,Object>> resultMap =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,Map<String,Object>>>(){});
+                    
+                    Set<Configuration> result = new HashSet<Configuration>();
+                    for(Map.Entry<String,Map<String,Object>> entry : resultMap.entrySet()) {
+                        result.add(new Configuration(entry.getKey(),entry.getValue().get("value")));
+                    }
+                    return result;
+                default:
+                    log.error("error retrieving list of configuration keys: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving list of configuration keys: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Return the configuration with the given key, or null if it does not exist
+     * @param key
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Configuration getConfiguration(String key) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CONFIG_SERVICE + "/data/" + URLEncoder.encode(key,"utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("configuration {} retrieved successfully",key);
+                    ObjectMapper mapper = new ObjectMapper();
+                    Map<String,Object> resultMap =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,Object>>(){});
+
+                    if(resultMap.isEmpty()) {
+                        return null;
+                    } else {
+                        return new Configuration(key,resultMap.get(key));
+                    }
+                case 404:
+                    log.info("configuration with key {} does not exist", key);
+                    return null;
+                default:
+                    log.error("error retrieving configuration {}: {} {}",new Object[] {key,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving configuration "+key+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Update the configuration "key" with the given value. Value can be either a list of values or one of the
+     * primitive types String, Boolean, Integer, Double
+     * @param key
+     * @param value
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void setConfiguration(String key, final Object value) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CONFIG_SERVICE + "/data/" + URLEncoder.encode(key,"utf-8");
+
+        HttpPost post = new HttpPost(serviceUrl);
+        post.setHeader("Content-Type", "application/json");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ObjectMapper mapper = new ObjectMapper();
+                if(value instanceof Collection) {
+                    mapper.writeValue(outstream,value);
+                } else {
+                    mapper.writeValue(outstream, Collections.singletonList(value.toString()));
+                }
+            }
+        };
+        post.setEntity(new EntityTemplate(cp));
+        
+        try {
+
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("configuration {} updated successfully",key);
+                    break;
+                case 404:
+                    log.error("configuration with key {} does not exist",key);
+                    throw new NotFoundException("configuration with key "+key+" does not exist");
+                default:
+                    log.error("error updating configuration {}: {} {}",new Object[] {key,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating configuration "+key+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }        
+    }
+
+    /**
+     * Remove the configuration with the given key.
+     *
+     * @param key
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void deleteConfiguration(String key) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CONFIG_SERVICE + "/data/" + URLEncoder.encode(key,"utf-8");
+
+        HttpDelete delete = new HttpDelete(serviceUrl);
+            
+        try {
+            HttpResponse response = httpClient.execute(delete);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("configuration {} deleted successfully",key);
+                    break;
+                case 404:
+                    log.error("configuration with key {} does not exist",key);
+                    throw new NotFoundException("configuration with key "+key+" does not exist");
+                default:
+                    log.error("error deleting configuration {}: {} {}",new Object[] {key,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error deleting configuration "+key+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            delete.releaseConnection();
+        }
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ContextClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ContextClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ContextClient.java
new file mode 100644
index 0000000..a066e47
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ContextClient.java
@@ -0,0 +1,80 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpDelete;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+
+/**
+ * Context Client 
+ * 	
+ * @author Sergio Fernández
+ *
+ */
+public class ContextClient {
+	
+    private static Logger log = LoggerFactory.getLogger(ContextClient.class);
+
+    private ClientConfiguration config;
+
+    public ContextClient(ClientConfiguration config) {
+        this.config = config;
+    }
+    
+    public boolean delete(String uri) {
+    	boolean result = false;
+        HttpClient httpClient = HTTPUtil.createClient(config);
+       
+        HttpDelete delete = new HttpDelete(uri);
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(delete);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug(uri + "cleanned");
+                    result = true;
+                    break;
+                case 404:
+                    log.error(uri + " is not a suitable context");
+                    result = false;
+                default:
+                    log.error("error cleanning context: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});                
+            }
+        
+        } catch (ClientProtocolException e) {
+			log.error(e.getMessage(), e);
+			result = false;
+		} catch (IOException e) {
+			log.error(e.getMessage(), e);
+			result = false;
+		} finally {
+		    delete.releaseConnection();
+        }
+        return result;
+
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/CoresClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/CoresClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/CoresClient.java
new file mode 100644
index 0000000..4092a55
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/CoresClient.java
@@ -0,0 +1,297 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.exception.NotFoundException;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import com.google.common.io.ByteStreams;
+import com.google.common.io.CharStreams;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpDelete;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.client.methods.HttpPut;
+import org.apache.http.entity.ContentProducer;
+import org.apache.http.entity.EntityTemplate;
+import org.codehaus.jackson.JsonParser;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.net.URLEncoder;
+import java.util.List;
+
+/**
+ * A client allowing to retrieve and configure the SOLR cores that are registered in the LMF server.
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class CoresClient {
+
+    private static Logger log = LoggerFactory.getLogger(CoresClient.class);
+
+    private static final String URL_CORES_SERVICE  = "/solr/cores";
+
+    private ClientConfiguration config;
+
+    public CoresClient(ClientConfiguration config) {
+        this.config = config;
+    }
+
+
+    /**
+     * Retrieve a list of all core names registered and activated in the LMF server.
+     * 
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public List<String> listCores() throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CORES_SERVICE;
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("active cores retrieved successfully");
+                    ObjectMapper mapper = new ObjectMapper();
+                    mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
+                    List<String> result =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<List<String>>(){});
+
+                    return result;
+
+                default:
+                    log.error("error retrieving active cores: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving active cores: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Return the LDPath program configured for the core with the name passed as argument. 
+     * 
+     * Note that this library provides no further functionality for evaluating LDPath programs. You may use the
+     * separate LDPath libraries at http://code.google.com/p/ldpath/.
+     * 
+     * @param coreName name of the core for which to retrieve the LDPath program
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public String getCoreConfiguration(String coreName) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CORES_SERVICE + "/" + URLEncoder.encode(coreName,"utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "text/plain");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("core {} retrieved successfully",coreName);
+                    return CharStreams.toString(new InputStreamReader(response.getEntity().getContent(),"utf-8"));
+                default:
+                    log.error("error retrieving core {}: {} {}",new Object[] {coreName,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving core "+coreName+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Create the core configuration for the given core using the LDPath program passed  as argument.
+     *
+     * Note that this library provides no further functionality for evaluating LDPath programs. You may use the
+     * separate LDPath libraries at http://code.google.com/p/ldpath/.
+     *
+     * @param coreName     the name of the core to update
+     * @param coreProgram  the LDPath program to use as core configuration
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void createCoreConfiguration(String coreName, final String coreProgram) throws IOException, LMFClientException {
+        createCoreConfiguration(coreName, new ByteArrayInputStream(coreProgram.getBytes("utf-8")));
+    }
+
+
+    /**
+     * Update the core configuration for the given core using the LDPath program passed  as argument.
+     *
+     * Note that this library provides no further functionality for evaluating LDPath programs. You may use the
+     * separate LDPath libraries at http://code.google.com/p/ldpath/.
+     *
+     * @param coreName     the name of the core to update
+     * @param coreProgram  InputStream providing the LDPath program to use as core configuration
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void createCoreConfiguration(String coreName, final InputStream coreProgram) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CORES_SERVICE + "/" + URLEncoder.encode(coreName,"utf-8");
+
+        HttpPost post = new HttpPost(serviceUrl);
+        post.setHeader("Content-Type", "text/plain");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(coreProgram,outstream);
+            }
+        };
+        post.setEntity(new EntityTemplate(cp));
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(post);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("core {} updated successfully",coreName);
+                    break;
+                default:
+                    log.error("error updating core {}: {} {}",new Object[] {coreName,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating core "+coreName+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Set/update the core configuration for the given core using the LDPath program passed  as argument.
+     *
+     * Note that this library provides no further functionality for evaluating LDPath programs. You may use the
+     * separate LDPath libraries at http://code.google.com/p/ldpath/.
+     *
+     * @param coreName     the name of the core to update
+     * @param coreProgram  the LDPath program to use as core configuration
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void updateCoreConfiguration(String coreName, final String coreProgram) throws IOException, LMFClientException {
+        updateCoreConfiguration(coreName,new ByteArrayInputStream(coreProgram.getBytes("utf-8")));
+    }
+
+    /**
+     * Update the core configuration for the given core using the LDPath program passed  as argument.
+     *
+     * Note that this library provides no further functionality for evaluating LDPath programs. You may use the
+     * separate LDPath libraries at http://code.google.com/p/ldpath/.
+     *
+     * @param coreName     the name of the core to update
+     * @param coreProgram  InputStream providing the LDPath program to use as core configuration
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void updateCoreConfiguration(String coreName, final InputStream coreProgram) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CORES_SERVICE + "/" + URLEncoder.encode(coreName,"utf-8");
+
+        HttpPut put = new HttpPut(serviceUrl);
+        put.setHeader("Content-Type", "text/plain");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(coreProgram,outstream);
+            }
+        };
+        put.setEntity(new EntityTemplate(cp));
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(put);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("core {} updated successfully",coreName);
+                    break;
+                default:
+                    log.error("error updating core {}: {} {}",new Object[] {coreName,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating core "+coreName+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            put.releaseConnection();
+        }
+    }
+
+
+    /**
+     * Remove the core with the name passed as argument.
+     *
+     * @param coreName   name of the core to delete
+     * @throws IOException
+     * @throws NotFoundException  in case the core with this name does not exist
+     * @throws LMFClientException
+     */
+    public void deleteCore(String coreName) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_CORES_SERVICE + "/" + URLEncoder.encode(coreName,"utf-8");
+
+        HttpDelete delete = new HttpDelete(serviceUrl);
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(delete);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("core {} deleted successfully",coreName);
+                    break;
+                case 404:
+                    log.error("core {} does not exist and could not be deleted", coreName);
+                    throw new NotFoundException("core "+coreName+" does not exist and could not be deleted");
+                default:
+                    log.error("error deleting core {}: {} {}",new Object[] {coreName,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating core "+coreName+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            delete.releaseConnection();
+        }
+    }
+    
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ImportClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ImportClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ImportClient.java
new file mode 100644
index 0000000..e389e5d
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ImportClient.java
@@ -0,0 +1,173 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import com.google.common.io.ByteStreams;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.ResponseHandler;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.ContentProducer;
+import org.apache.http.entity.EntityTemplate;
+import org.apache.http.util.EntityUtils;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * This client class provides support for importing ontologies in various formats into the Linked Media Framework.
+ * 
+ * Author: Sebastian Schaffert
+ */
+public class ImportClient {
+
+    private static Logger log = LoggerFactory.getLogger(ImportClient.class);
+
+    private static final String URL_TYPES_SERVICE = "/import/types";
+    private static final String URL_UPLOAD_SERVICE = "/import/upload";
+
+    private ClientConfiguration config;
+    
+    private Set<String> acceptableTypes;
+
+    public ImportClient(ClientConfiguration config) {
+        this.acceptableTypes = new HashSet<String>();
+        this.config = config;
+        try {
+            this.acceptableTypes = getSupportedTypes();
+        } catch (IOException e) {
+            log.error("I/O Exception while trying to retrieve supported types",e);
+        } catch (LMFClientException e) {
+            log.error("Client Exception while trying to retrieve supported types",e);
+        }
+    }
+
+    /**
+     * Return a set of mime types representing the types that are accepted by the LMF server.
+     * 
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Set<String> getSupportedTypes() throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_TYPES_SERVICE;
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("list of import types retrieved successfully");
+                    ObjectMapper mapper = new ObjectMapper();
+                    Set<String> result =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Set<String>>(){});
+                    return result;
+                 default:
+                    log.error("error retrieving list of import types: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving list of import types: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Upload/Import a dataset in the LMF Server. The dataset is given as an Inputstream that contains data of the
+     * mime type passed as argument. The mime type must be one of the acceptable types of the server.
+     *
+     * @param in InputStream to read the dataset from; will be consumed by this method
+     * @param mimeType mime type of the input data
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void uploadDataset(final InputStream in, final String mimeType) throws IOException, LMFClientException {
+        //Preconditions.checkArgument(acceptableTypes.contains(mimeType));
+
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpPost post = HTTPUtil.createPost(URL_UPLOAD_SERVICE, config);
+        post.setHeader("Content-Type", mimeType);
+        
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(in,outstream);
+            }
+        };
+        post.setEntity(new EntityTemplate(cp));
+        
+        ResponseHandler<Boolean> handler = new ResponseHandler<Boolean>() {
+            @Override
+            public Boolean handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
+                EntityUtils.consume(response.getEntity());
+                switch(response.getStatusLine().getStatusCode()) {
+                    case 200:
+                        log.debug("dataset uploaded updated successfully");
+                        return true;
+                    case 412:
+                        log.error("mime type {} not acceptable by import service",mimeType);
+                        return false;
+                    default:
+                        log.error("error uploading dataset: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                        return false;
+                }
+            }
+        };
+
+        try {
+            httpClient.execute(post, handler);
+        } catch(IOException ex) {
+            post.abort();
+            throw ex;
+        } finally {
+            post.releaseConnection();
+        }
+
+    }
+
+    /**
+     * Upload the data contained in the string using the given mime type; convenience method wrapping the generic
+     * InputStream-based method.
+     *
+     * @param data
+     * @param mimeType
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void uploadDataset(String data, String mimeType) throws IOException, LMFClientException {
+        uploadDataset(new ByteArrayInputStream(data.getBytes("utf-8")), mimeType);
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/LDPathClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/LDPathClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/LDPathClient.java
new file mode 100644
index 0000000..c581e9f
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/LDPathClient.java
@@ -0,0 +1,164 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.ContentFormatException;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.exception.NotFoundException;
+import at.newmedialab.lmf.client.model.rdf.RDFNode;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import at.newmedialab.lmf.client.util.RDFJSONParser;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.codehaus.jackson.JsonParser;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.net.URLEncoder;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Add file description here!
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class LDPathClient {
+
+    private static Logger log = LoggerFactory.getLogger(LDPathClient.class);
+
+    private static final String URL_PATH_SERVICE  = "/ldpath/path";
+    private static final String URL_PROGRAM_SERVICE = "/ldpath/program";
+
+
+    private ClientConfiguration config;
+
+    public LDPathClient(ClientConfiguration config) {
+        this.config = config;
+    }
+
+
+    /**
+     * Evaluate the path query passed as second argument, starting at the resource with the uri given as first argument.
+     * Returns a List of RDFNode objects.
+     *
+     *
+     * @param uri  the uri of the resource where to start the path evaluation
+     * @param path the path to evaluate
+     * @return a list of RDFNodes representing the result of the path evaluation as returned by the server
+     * @throws LMFClientException
+     * @throws IOException
+     */
+    public List<RDFNode> evaluatePath(String uri, String path) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_PATH_SERVICE + "?path=" + URLEncoder.encode(path, "utf-8")
+                                                                  + "&uri="  + URLEncoder.encode(uri, "utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("LDPath Path Query {} evaluated successfully",path);
+                    ObjectMapper mapper = new ObjectMapper();
+                    mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
+                    List<Map<String,String>> serverResult =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<List<Map<String,String>>>(){});
+
+                    
+                    List<RDFNode> result = new ArrayList<RDFNode>();
+                    for(Map<String,String> value : serverResult) {
+                        result.add(RDFJSONParser.parseRDFJSONNode(value));
+                    }
+                    return result;
+                case 400:
+                    log.error("the server did not accept the uri ({}) or path ({}) arguments",uri,path);
+                    throw new ContentFormatException("the server did not accept the uri ("+uri+") or path ("+path+") arguments");
+                case 404:
+                    log.error("the resource with URI {} does not exist on the server",uri);
+                    throw new NotFoundException("the resource with URI "+uri+" does not exist on the server");
+                default:
+                    log.error("error evaluating LDPath Path Query {}: {} {}",new Object[] {path,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error evaluating LDPath Path Query "+path+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+
+    }
+    
+    
+    public Map<String,List<RDFNode>> evaluateProgram(String uri, String program) throws LMFClientException, IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_PROGRAM_SERVICE + "?program=" + URLEncoder.encode(program, "utf-8")
+                                                                                   + "&uri="  + URLEncoder.encode(uri, "utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("LDPath Program Query evaluated successfully:\n{}",program);
+                    ObjectMapper mapper = new ObjectMapper();
+                    mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
+                    Map<String,List<Map<String,String>>> serverResult =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,List<Map<String,String>>>>(){});
+
+
+                    Map<String,List<RDFNode>> result = new HashMap<String, List<RDFNode>>();
+                    for(Map.Entry<String,List<Map<String,String>>> field : serverResult.entrySet()) {
+                        List<RDFNode> row = new ArrayList<RDFNode>();
+                        for(Map<String,String> node : field.getValue()) {
+                            row.add(RDFJSONParser.parseRDFJSONNode(node));
+                        }
+                        result.put(field.getKey(),row);
+                    }
+                    return result;
+                case 400:
+                    log.error("the server did not accept the uri ({}) or program ({}) arguments",uri,program);
+                    throw new ContentFormatException("the server did not accept the uri ("+uri+") or program ("+program+") arguments");
+                case 404:
+                    log.error("the resource with URI {} does not exist on the server",uri);
+                    throw new NotFoundException("the resource with URI "+uri+" does not exist on the server");
+                default:
+                    log.error("error evaluating LDPath Program Query: {} {}",new Object[] {response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error evaluating LDPath Program Query: "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ResourceClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ResourceClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ResourceClient.java
new file mode 100644
index 0000000..616be9d
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/ResourceClient.java
@@ -0,0 +1,372 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.ContentFormatException;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.exception.NotFoundException;
+import at.newmedialab.lmf.client.model.content.Content;
+import at.newmedialab.lmf.client.model.content.StreamContent;
+import at.newmedialab.lmf.client.model.meta.Metadata;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import at.newmedialab.lmf.client.util.RDFJSONParser;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.io.ByteStreams;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.ResponseHandler;
+import org.apache.http.client.methods.HttpDelete;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpOptions;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.client.methods.HttpPut;
+import org.apache.http.entity.ContentProducer;
+import org.apache.http.entity.EntityTemplate;
+import org.apache.http.util.EntityUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.util.Map;
+
+/**
+ * Add file description here!
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class ResourceClient {
+
+    private static Logger log = LoggerFactory.getLogger(ResourceClient.class);
+
+    private static final String URL_RESOURCE_SERVICE = "/resource";
+    
+    private ClientConfiguration config;
+
+    public ResourceClient(ClientConfiguration config) {
+        this.config = config;
+
+    }
+
+    /**
+     * Create a resource in the remote LMF installation
+     * @param uri
+     * @return
+     * @throws IOException
+     */
+    public boolean createResource(String uri) throws IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+            
+        HttpPost post = new HttpPost(getServiceUrl(uri));
+        
+        try {
+            
+            HttpResponse response = httpClient.execute(post);
+            
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200: 
+                    log.debug("resource {} already existed, not creating new",uri);
+                    return true;
+                case 201: 
+                    log.debug("resource {} created",uri);
+                    return true;
+                default:
+                    log.error("error creating resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    return true;
+            }
+            
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            return false;
+        } finally {
+            post.releaseConnection();
+        }
+    }
+
+    /**
+     * Test whether the resource with the provided URI exists.
+     * <p/>
+     * Uses an OPTIONS call to the resource web service to determine whether the resource exists or not
+     *
+     * @param uri
+     * @return
+     * @throws IOException
+     */
+    public boolean existsResource(String uri) throws IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpOptions options = new HttpOptions(getServiceUrl(uri));
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(options);
+
+            if(response.containsHeader("Access-Control-Allow-Methods") && response.getFirstHeader("Access-Control-Allow-Methods").getValue().equals("POST")) {
+                return false;
+            } else if(response.containsHeader("Access-Control-Allow-Methods") && response.getFirstHeader("Access-Control-Allow-Methods").getValue().contains("GET")) {
+                return true;
+            } else {
+                log.warn("OPTIONS response did not contain a access-control-allow-methods header");
+                return false; 
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            return false;
+        } finally {
+            options.releaseConnection();
+        }
+    }
+
+    /**
+     * Return the resource metadata for the resource with the given URI, if it exists. Returns null if the
+     * resource exists but there is no metadata. Throws an exception if the resource does not exist or some
+     * other error code was returned.
+     *
+     * @param uri
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Metadata getResourceMetadata(String uri) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpGet get = new HttpGet(getServiceUrl(uri));
+        get.setHeader("Accept", "application/rdf+json; rel=meta");
+        
+        try {
+            
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("metadata for resource {} retrieved",uri);
+                    Map<String,Metadata> result = RDFJSONParser.parseRDFJSON(response.getEntity().getContent());
+                    if(result.containsKey(uri)) {
+                        return result.get(uri);
+                    } else {
+                        return null;
+                    }
+                case 406:
+                    log.error("server does not support metadata type application/json for resource {}, cannot retrieve", uri);
+                    throw new ContentFormatException("server does not support metadata type application/json for resource "+uri);
+                case 404:
+                    log.error("resource {} does not exist, cannot retrieve", uri);
+                    throw new NotFoundException("resource "+uri+" does not exist, cannot retrieve");
+                default:
+                    log.error("error retrieving resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving resource "+uri+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            throw new LMFClientException("could not encode URI parameter");
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Update (overwrite) the metadata of the resource identified by the given uri. The metadata will be serialised to
+     * application/json and sent to the Linked Media Framework server. The given metadata will override any metadata
+     * for the resource already existing on the server. The resource has to exist or be created before updating, otherwise
+     * the method will throw a NotFoundException.
+     *
+     * @param uri        the URI of the resource to update
+     * @param metadata   the metadata to upload to the resource
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void updateResourceMetadata(final String uri, final Metadata metadata) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpPut put = new HttpPut(getServiceUrl(uri));
+        put.setHeader("Content-Type", "application/rdf+json; rel=meta");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                RDFJSONParser.serializeRDFJSON(ImmutableMap.of(uri, metadata), outstream);
+            }
+        };
+        put.setEntity(new EntityTemplate(cp));
+
+        try {
+            
+            HttpResponse response = httpClient.execute(put);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("metadata for resource {} updated",uri);
+                    break;
+                case 415:
+                    log.error("server does not support metadata type application/json for resource {}, cannot update", uri);
+                    throw new ContentFormatException("server does not support metadata type application/json for resource "+uri);
+                case 404:
+                    log.error("resource {} does not exist, cannot update", uri);
+                    throw new NotFoundException("resource "+uri+" does not exist, cannot update");
+                default:
+                    log.error("error updating resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error updating resource "+uri+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            throw new LMFClientException("could not encode URI parameter");
+        } finally {
+            put.releaseConnection();
+        }
+    }
+
+    /**
+     * Retrieve the (human-readable) content of the given mimeType of the given resource. Will return a content
+     * object that allows reading the input stream. In case no content of the given mime type exists for the resource,
+     * will throw a ContentFormatException.
+     *
+     * @param uri
+     * @param mimeType
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public Content getResourceContent(String uri, String mimeType) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpGet get = new HttpGet(getServiceUrl(uri));
+        get.setHeader("Accept", mimeType+"; rel=content");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("metadata for resource {} retrieved",uri);
+                    Content content = new StreamContent(response.getEntity().getContent(),response.getEntity().getContentType().getValue(),response.getEntity().getContentLength());
+                    return content;
+                case 406:
+                    log.error("server does not offer content type {} for resource {}, cannot retrieve", mimeType, uri);
+                    throw new ContentFormatException("server does not offer content type "+mimeType+" for resource "+uri);
+                case 404:
+                    log.error("resource {} does not exist, cannot retrieve content", uri);
+                    throw new NotFoundException("resource "+uri+" does not exist, cannot retrieve");
+                default:
+                    log.error("error retrieving resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error retrieving resource "+uri+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+            throw new LMFClientException("could not encode URI parameter");
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Update the content of the resource identified by the URI given as argument. The resource has to exist before
+     * content can be uploaded to it. Any existing content will be overridden. The stream of the content object
+     * will be consumed by this method. Throws ContentFormatException if the content type is not supported,
+     * NotFoundException if the resource does not exist.
+     * @param uri
+     * @param content
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public void updateResourceContent(final String uri, final Content content) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpPut put = new HttpPut(getServiceUrl(uri));
+        put.setHeader("Content-Type", content.getMimeType()+"; rel=content");
+        ContentProducer cp = new ContentProducer() {
+            @Override
+            public void writeTo(OutputStream outstream) throws IOException {
+                ByteStreams.copy(content.getStream(),outstream);
+            }
+        };
+        put.setEntity(new EntityTemplate(cp));
+        
+        ResponseHandler<Boolean> handler = new ResponseHandler<Boolean>() {
+            @Override
+            public Boolean handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
+                EntityUtils.consume(response.getEntity());
+                switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("content for resource {} updated",uri);
+                    return true;
+                case 406:
+                    log.error("server does not support content type {} for resource {}, cannot update", content.getMimeType(),uri);
+                    return false;
+                case 404:
+                    log.error("resource {} does not exist, cannot update", uri);
+                    return false;
+                default:
+                    log.error("error updating resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    return false;
+                }
+            }
+        };
+
+        try {
+            httpClient.execute(put, handler);
+        } catch(IOException ex) {
+            put.abort();
+            throw ex;
+        } finally {
+            put.releaseConnection();
+        }
+
+    }
+    
+    
+    public void deleteResource(String uri) throws IOException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        HttpDelete delete = new HttpDelete(getServiceUrl(uri));
+        
+        try {
+            
+            HttpResponse response = httpClient.execute(delete);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("resource {} deleted",uri);
+                    break;
+                case 400:
+                    log.error("resource {} invalid, cannot delete", uri);
+                    break;
+                case 404:
+                    log.error("resource {} does not exist, cannot delete", uri);
+                    break;
+                default:
+                    log.error("error deleting resource {}: {} {}",new Object[] {uri,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+            }
+
+        } catch (UnsupportedEncodingException e) {
+            log.error("could not encode URI parameter",e);
+        } finally {
+            delete.releaseConnection();
+        }
+    }
+    
+    private String getServiceUrl(String uri) throws UnsupportedEncodingException {
+        return config.getLmfUri() + URL_RESOURCE_SERVICE + "?uri=" + URLEncoder.encode(uri,"utf-8");    
+    }
+    
+}

http://git-wip-us.apache.org/repos/asf/incubator-marmotta/blob/c32963d5/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/SPARQLClient.java
----------------------------------------------------------------------
diff --git a/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/SPARQLClient.java b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/SPARQLClient.java
new file mode 100644
index 0000000..4524928
--- /dev/null
+++ b/lmf-client/lmf-client-java/src/main/java/at/newmedialab/lmf/client/clients/SPARQLClient.java
@@ -0,0 +1,227 @@
+/**
+ * Copyright (C) 2013 Salzburg Research.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package at.newmedialab.lmf.client.clients;
+
+import at.newmedialab.lmf.client.ClientConfiguration;
+import at.newmedialab.lmf.client.exception.LMFClientException;
+import at.newmedialab.lmf.client.model.rdf.BNode;
+import at.newmedialab.lmf.client.model.rdf.Literal;
+import at.newmedialab.lmf.client.model.rdf.RDFNode;
+import at.newmedialab.lmf.client.model.rdf.URI;
+import at.newmedialab.lmf.client.model.sparql.SPARQLResult;
+import at.newmedialab.lmf.client.util.HTTPUtil;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.codehaus.jackson.JsonParser;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.type.TypeReference;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.net.URLEncoder;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Add file description here!
+ * <p/>
+ * Author: Sebastian Schaffert
+ */
+public class SPARQLClient {
+
+    private static Logger log = LoggerFactory.getLogger(SPARQLClient.class);
+
+    private static final String URL_QUERY_SERVICE  = "/sparql/select";
+    private static final String URL_UPDATE_SERVICE = "/sparql/update";
+
+    private ClientConfiguration config;
+
+    public SPARQLClient(ClientConfiguration config) {
+        this.config = config;
+    }
+
+    /**
+     * Run a SPARQL Select query against the LMF Server and return the results as SPARQL Result. Results will be
+     * transfered and parsed using the SPARQL JSON format.
+     * @param query a SPARQL Select query to run on the database
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    @SuppressWarnings("unchecked")
+    public SPARQLResult select(String query) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_QUERY_SERVICE + "?query=" + URLEncoder.encode(query, "utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/sparql-results+json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("SPARQL Query {} evaluated successfully",query);
+                    ObjectMapper mapper = new ObjectMapper();
+                    mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
+                    Map<String,Map<String,List<?>>> resultMap =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,Map<String,List<?>>>>(){});
+
+                    if(resultMap.isEmpty()) {
+                        return null;
+                    } else {
+                        List<?> head = resultMap.get("head").get("vars");
+                        Set<String> fieldNames = new HashSet<String>();
+                        for(Object o : head) {
+                            if(o instanceof String) {
+                                fieldNames.add((String)o);
+                            }
+                        }
+
+                        SPARQLResult result = new SPARQLResult(fieldNames);
+
+                        List<?> bindings = resultMap.get("results").get("bindings");
+                        for(Object o : bindings) {
+                            if(o instanceof Map) {
+                                Map<String,RDFNode> row = new HashMap<String, RDFNode>();
+                                for(Map.Entry<String,?> entry : ((Map<String,?>)o).entrySet()) {
+                                    Map<String,String> nodeDef = (Map<String,String>) entry.getValue();
+                                    RDFNode node = null;
+                                    if("uri".equalsIgnoreCase(nodeDef.get("type"))) {
+                                        node = new URI(nodeDef.get("value"));
+                                    } else if("literal".equalsIgnoreCase(nodeDef.get("type")) ||
+                                              "typed-literal".equalsIgnoreCase(nodeDef.get("type"))) {
+                                        String lang = nodeDef.get("xml:lang");
+                                        String datatype = nodeDef.get("datatype");
+
+                                        if(lang != null) {
+                                            node = new Literal(nodeDef.get("value"),lang);
+                                        } else if(datatype != null) {
+                                            node = new Literal(nodeDef.get("value"),new URI(datatype));
+                                        } else {
+                                            node = new Literal(nodeDef.get("value"));
+                                        }
+                                    } else if("bnode".equalsIgnoreCase(nodeDef.get("type"))) {
+                                        node = new BNode(nodeDef.get("value"));
+                                    } else {
+                                        log.error("unknown result node type: {}",nodeDef.get("type"));
+                                    }
+                                    
+                                    if(node != null) {
+                                        row.put(entry.getKey(),node);
+                                    }
+                                }
+                                result.add(row);
+                            }
+                        }
+                        return result;
+                    }
+                default:
+                    log.error("error evaluating SPARQL Select Query {}: {} {}",new Object[] {query,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error evaluating SPARQL Select Query "+query+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Carry out a SPARQL ASK Query and return either true or false, depending on the query result.
+     *
+     * @param askQuery
+     * @return
+     * @throws IOException
+     * @throws LMFClientException
+     */
+    public boolean ask(String askQuery) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_QUERY_SERVICE + "?query=" + URLEncoder.encode(askQuery, "utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        get.setHeader("Accept", "application/sparql-results+json");
+        
+        try {
+
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("SPARQL ASK Query {} evaluated successfully",askQuery);
+                    ObjectMapper mapper = new ObjectMapper();
+                    mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
+                    Map<String,Object> resultMap =
+                            mapper.readValue(response.getEntity().getContent(),new TypeReference<Map<String,Object>>(){});
+
+                    if(resultMap.isEmpty()) {
+                        return false;
+                    } else {
+                        Boolean result = resultMap.get("boolean") != null && ((String)resultMap.get("boolean")).equalsIgnoreCase("true");
+                        return result;
+                    }
+                default:
+                    log.error("error evaluating SPARQL ASK Query {}: {} {}",new Object[] {askQuery,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error evaluating SPARQL ASK Query "+askQuery+": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+
+    /**
+     * Execute a SPARQL Update query according to the SPARQL 1.1 standard. The query will only be passed to the server,
+     * which will react either with ok (in this the method simply returns) or with error (in this case, the method
+     * throws an LMFClientException).
+     *
+     * @param updateQuery         the SPARQL Update 1.1 query string
+     * @throws IOException        in case a connection problem occurs
+     * @throws LMFClientException in case the server returned and error and did not execute the update
+     */
+    public void update(String updateQuery) throws IOException, LMFClientException {
+        HttpClient httpClient = HTTPUtil.createClient(config);
+
+        String serviceUrl = config.getLmfUri() + URL_UPDATE_SERVICE + "?update=" + URLEncoder.encode(updateQuery, "utf-8");
+
+        HttpGet get = new HttpGet(serviceUrl);
+        
+        try {
+                
+            HttpResponse response = httpClient.execute(get);
+
+            switch(response.getStatusLine().getStatusCode()) {
+                case 200:
+                    log.debug("SPARQL UPDATE Query {} evaluated successfully",updateQuery);
+                    break;
+                default:
+                    log.error("error evaluating SPARQL UPDATE Query {}: {} {}",new Object[] {updateQuery,response.getStatusLine().getStatusCode(),response.getStatusLine().getReasonPhrase()});
+                    throw new LMFClientException("error evaluating SPARQL UPDATE Query "+updateQuery +": "+response.getStatusLine().getStatusCode() + " " + response.getStatusLine().getReasonPhrase());
+            }
+
+        } finally {
+            get.releaseConnection();
+        }
+    }
+    
+}