svn commit: r527197 - /incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java

[tt...@apache.org]

Author: tterm
Date: Tue Apr 10 09:58:29 2007
New Revision: 527197

URL: http://svn.apache.org/viewvc?view=rev&rev=527197
Log:
SM-929 eip message filter switch predicate where you can easily turn on/off the exchange flow in a message filter depending on a property

Added:
    incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java

Added: incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java
URL: http://svn.apache.org/viewvc/incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java?view=auto&rev=527197
==============================================================================
--- incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java (added)
+++ incubator/servicemix/trunk/deployables/serviceengines/servicemix-eip/src/main/java/org/apache/servicemix/eip/support/SwitchPredicate.java Tue Apr 10 09:58:29 2007
@@ -0,0 +1,170 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.servicemix.eip.support;
+
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.DefaultResourceLoader;
+import org.springframework.beans.factory.InitializingBean;
+
+import javax.jbi.messaging.MessageExchange;
+import javax.jbi.messaging.NormalizedMessage;
+import java.io.File;
+import java.io.IOException;
+import java.util.Properties;
+
+/**
+ * switch (on/off) predicate based on a property that can come from
+ * 1. a system property
+ * 2. a property from a property file (specified as Spring resource)
+ * 3. a property from the exchange
+ * 4. swtich on/off via JMX MBean (not yet implemented)
+ * <p/>
+ * the property is interpreted as a boolean value
+ * If fromExchange is true --> 3.
+ * If propertyResource is specified --> 2.
+ * else --> 1.
+ *
+ * @org.apache.xbean.XBean element="switch-predicate"
+ */
+public class SwitchPredicate implements InitializingBean, Predicate {
+
+    private static final Log log = LogFactory.getLog(SwitchPredicate.class);
+
+    // property resource optionally
+    private Resource propertyResource;
+
+    // use property from exchange
+    private boolean fromExchange = false;
+
+    // property name
+    private String propertyName = "on";
+
+    private Boolean on = Boolean.FALSE;
+
+    private File propertyFile = null;
+
+    private boolean dirty = false;
+
+    public void afterPropertiesSet() throws Exception {
+        try {
+            Properties props = null;
+            if (propertyResource != null && propertyResource.exists()) {
+                // get property from properties file
+                propertyFile = propertyResource.getFile();
+                if (log.isDebugEnabled()) {
+                    log.debug("loading property file: " + propertyFile.getAbsolutePath());
+                }
+                props = new Properties();
+                props.load(propertyResource.getInputStream());
+            } else {
+                // property is a system property
+                props = System.getProperties();
+            }
+            String value = props.getProperty(propertyName);
+            if (value != null) {
+                on = Boolean.valueOf(value);
+            }
+        } catch (IOException e) {
+            log.error("could not load switch property file - filter is off", e);
+            on = Boolean.FALSE;
+        }
+        dirty = false;
+    }
+
+    public boolean isOn() {
+        return on.booleanValue();
+    }
+
+    public void setOn(boolean status) {
+        on = new Boolean(status);
+    }
+
+    public String getPropertyName() {
+        return propertyName;
+    }
+
+    public void setPropertyName(String newPropertyName) {
+        propertyName = newPropertyName;
+        dirty = true;
+    }
+
+    public Resource getPropertyResource() {
+        return propertyResource;
+    }
+
+    public void setPropertyResource(Resource newPropertyResource) {
+        propertyResource = newPropertyResource;
+    }
+
+    public boolean getFromExchange() {
+        return fromExchange;
+    }
+
+    public void setFromExchange(boolean fromExchange) {
+        this.fromExchange = fromExchange;
+    }
+
+    public void createResource(String resource) {
+        if (resource != null) {
+            DefaultResourceLoader resourceLoader = new DefaultResourceLoader();
+            Resource tempPropertyResource = resourceLoader.getResource(resource);
+            if (tempPropertyResource != null && tempPropertyResource.exists()) {
+                propertyResource = tempPropertyResource;
+                dirty = true;
+            }
+        }
+    }
+
+    public String showResource() throws IOException {
+        return propertyResource.getURL().toExternalForm();
+    }
+
+    /* (non-Javadoc)
+    * @see org.apache.servicemix.components.eip.RoutingRule#matches(javax.jbi.messaging.MessageExchange)
+    */
+    public boolean matches(MessageExchange exchange) {
+        if (dirty) {
+            try {
+                afterPropertiesSet();
+            } catch (Exception e) {
+                return false;
+            }
+
+        }
+        Boolean match = Boolean.FALSE;
+        if (fromExchange) {
+            // property comes from exchange
+            try {
+                NormalizedMessage in = exchange.getMessage("in");
+                Object value = exchange.getProperty(propertyName);
+                if (value != null) {
+                    match = Boolean.valueOf(value.toString());
+                }
+            } catch (Exception e) {
+                log.warn("Could not evaluate xpath expression", e);
+                match = Boolean.FALSE;
+            }
+        } else {
+            // property comes in from external - use pre-evaluated value
+            match = on;
+        }
+        return match.booleanValue();
+    }
+}