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Posted to commits@tuscany.apache.org by ke...@apache.org on 2007/06/12 11:57:40 UTC
svn commit: r546443 - in
/incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo:
SampleBase.java SampleInfrastructure.java
specCodeSnippets/ObtainingDataGraphFromXml.java
Author: kelvingoodson
Date: Tue Jun 12 02:57:39 2007
New Revision: 546443
URL: http://svn.apache.org/viewvc?view=rev&rev=546443
Log:
Restructured the ObtainingDataGraphFromXml.java sample, and added some infrastructure to help with making other samples be clearer.
Added:
incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java (with props)
incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java (with props)
Modified:
incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/specCodeSnippets/ObtainingDataGraphFromXml.java
Added: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java
URL: http://svn.apache.org/viewvc/incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java?view=auto&rev=546443
==============================================================================
--- incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java (added)
+++ incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java Tue Jun 12 02:57:39 2007
@@ -0,0 +1,104 @@
+/**
+ *
+ * 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.tuscany.samples.sdo;
+
+import java.io.InputStream;
+
+import org.apache.tuscany.sdo.api.SDOUtil;
+
+import commonj.sdo.helper.HelperContext;
+import commonj.sdo.helper.XSDHelper;
+import commonj.sdo.impl.HelperProvider;
+
+public class SampleBase extends SampleInfrastructure {
+
+ protected HelperContext scope;
+
+
+ public SampleBase(int userLevel) {
+ super(userLevel);
+
+ }
+
+
+ protected HelperContext createScopeForTypes() {
+ commentary(
+ NOVICE,
+ "All MetaData for SDO types can be viewed as being held in an instance of HelperContext\n" +
+ "The Helper Context instance provides access to a collection of other helpers\n" +
+ "that you will see exercised in the SDO samples\n" +
+ "All the Helpers related to a given helper context instance know about the same set of types\n\n" +
+ "The SDO specification doesn't currently state how an SDO implementation should create a HelperContext\n" +
+ "So we use a Tuscany specific API to do this ...\n\n" +
+ "HelperContext scope = SDOUtil.createHelperContext();",
+
+ "Setting a new HelperContext scope for types for the next sample run"
+ );
+
+ HelperContext scope = SDOUtil.createHelperContext();
+ return scope;
+ }
+
+ protected HelperContext useDefaultScopeForTypes() {
+ commentary(
+ NOVICE,
+ "All MetaData for SDO types can be viewed as being held in an instance of HelperContext\n" +
+ "The Helper Context instance provides access to a collection of other helpers\n" +
+ "that you will see exercised in the SDO samples\n" +
+ "All the Helpers related to a given helper context instance know about the same set of types\n\n" +
+ "For most cases it's best to take control of the type scope by creating a new HelperContext,\n" +
+ "but a default helper context is provided and can be accessed using ...\n\n" +
+ "HelperContext scope = HelperProvider.getDefaultContext();\n\n" +
+ "A case in point where the default scope must be used is when using some of the DataGraph APIs\n" +
+ "which don't all support the type scoping extensions which were introduced in the SDO 2.1 specification",
+
+ "Retrieving the default HelperContext scope for types for the next sample run"
+ );
+
+ HelperContext scope = HelperProvider.getDefaultContext();
+ return scope;
+ }
+
+
+ protected void loadXMLSchemaFromFile(HelperContext scope, String fileName) {
+ commentary(NOVICE,
+ "If you want to create types dynamically by loading an XML schema you\n" +
+ "use an instance of XSDHelper. You get that helper from a HelperContext.\n" +
+ "After successful loading of a schema, the new types are available to every\n" +
+ "other helper belonging to the HelperContext instance\n\n" +
+ "XSDHelper xsdHelper = scope.getXSDHelper();",
+
+ "Using an XSDHelper again to create types from an XML schema file"
+ );
+
+ XSDHelper xsdHelper = scope.getXSDHelper();
+
+ try {
+ InputStream is = null;
+ is = ClassLoader.getSystemResourceAsStream(fileName);
+ xsdHelper.define(is, null);
+ is.close();
+ } catch (Exception e) {
+ somethingUnexpectedHasHappened(e);
+ }
+ }
+
+}
Propchange: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java
------------------------------------------------------------------------------
svn:eol-style = native
Propchange: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleBase.java
------------------------------------------------------------------------------
svn:keywords = Rev Date
Added: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java
URL: http://svn.apache.org/viewvc/incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java?view=auto&rev=546443
==============================================================================
--- incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java (added)
+++ incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java Tue Jun 12 02:57:39 2007
@@ -0,0 +1,124 @@
+/**
+ *
+ * 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.tuscany.samples.sdo;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.apache.tuscany.sdo.api.SDOUtil;
+
+import commonj.sdo.helper.HelperContext;
+
+public class SampleInfrastructure {
+
+
+ /*
+ * sample program infrastructure
+ */
+ protected int userLevel = NOVICE;
+ private Set commentaryHistory = new HashSet();
+
+ public SampleInfrastructure (int userLevel) {
+ this.userLevel = userLevel;
+ }
+
+ private static String hrule = "********************************************";
+ protected static final int NOVICE = 1;
+ protected static final int INTERMEDIATE = 2;
+ protected static final int ADVANCED = 3;
+
+ protected static final String noviceStr = " novice ";
+ protected static final String intermediateStr = " intermediate ";
+ protected static final String advancedStr = " advanced ";
+
+ public void banner(char borderChar, String text) {
+ if(text == null || text.length() == 0) {
+ System.out.println(hrule);
+ return;
+ }
+ String [] lines = text.split("\n");
+ int maxlinelen = 0;
+
+ for(int i=0; i<lines.length; i++) {
+ maxlinelen = lines[i].length() > maxlinelen ? lines[i].length() : maxlinelen;
+ }
+
+ StringBuffer buf = new StringBuffer();
+ for (int p = 0; p < maxlinelen + 4; p++) {
+ buf.append(borderChar);
+ }
+ buf.append("\n");
+ for(int l=0; l<lines.length; l++) {
+ buf.append(borderChar).append(" ");
+ buf.append(lines[l]);
+ for(int rem=lines[l].length()+2; rem < maxlinelen+3; rem++) buf.append(" ");
+ buf.append(borderChar).append("\n");
+ }
+ for (int p = 0; p < maxlinelen + 4; p++) {
+ buf.append(borderChar);
+ }
+ buf.append("\n");
+ System.out.println(buf.toString());
+ }
+
+ public void banner(String text) {
+ banner('-', text);
+ }
+
+ protected void commentary(int commentLevel, String text, String repeatText) {
+
+ if(commentLevel < userLevel) return;
+
+ if(repeatText != null) {
+ boolean alreadySeen = commentaryHistory.contains(text);
+ if(alreadySeen) {
+ commentary(commentLevel, repeatText);
+ } else {
+ commentary(commentLevel, text);
+ commentaryHistory.add(text);
+ }
+ } else {
+ commentary(userLevel, text);
+ }
+
+ }
+
+ protected void commentary(int commentLevel, String text) {
+ if(commentLevel >= userLevel) {
+ banner(text);
+ }
+ }
+
+ protected void somethingUnexpectedHasHappened(Exception e) {
+ banner('!',
+ "Something unexpected has gone wrong with the execution of this sample program\n" +
+ "Please take a look at the exception and see if its something wrong with your environment\n" +
+ "If you can't figure it out please send a note to the tuscany-users@ws.apache.org mailing list\n" +
+ "including the text of the exception and any other useful information, thanks");
+
+ e.printStackTrace();
+ }
+
+
+
+
+
+}
Propchange: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java
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svn:eol-style = native
Propchange: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/SampleInfrastructure.java
------------------------------------------------------------------------------
svn:keywords = Rev Date
Modified: incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/specCodeSnippets/ObtainingDataGraphFromXml.java
URL: http://svn.apache.org/viewvc/incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/specCodeSnippets/ObtainingDataGraphFromXml.java?view=diff&rev=546443&r1=546442&r2=546443
==============================================================================
--- incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/specCodeSnippets/ObtainingDataGraphFromXml.java (original)
+++ incubator/tuscany/java/sdo/sample/src/main/java/org/apache/tuscany/samples/sdo/specCodeSnippets/ObtainingDataGraphFromXml.java Tue Jun 12 02:57:39 2007
@@ -20,11 +20,17 @@
package org.apache.tuscany.samples.sdo.specCodeSnippets;
+import java.io.FileInputStream;
import java.io.InputStream;
+import org.apache.tuscany.samples.sdo.SampleBase;
+import org.apache.tuscany.samples.sdo.SampleInfrastructure;
import org.apache.tuscany.samples.sdo.SdoSampleConstants;
+import org.apache.tuscany.sdo.api.SDOUtil;
-import org.apache.tuscany.sdo.util.SDOUtil;
+
+import commonj.sdo.helper.HelperContext;
+import commonj.sdo.helper.XMLDocument;
import commonj.sdo.helper.XMLHelper;
import commonj.sdo.helper.XSDHelper;
import commonj.sdo.DataObject;
@@ -32,9 +38,9 @@
import commonj.sdo.Sequence;
/**
- * Demonstrates a variety of methods available to obtain the root DataObject
+ * This sample program demonstrates a variety of methods available to obtain the root DataObject
* contained within an xml representation of a DataGraph. This is currently a grey
- * area of the specification and this samples demonstrates spec compliant means, as
+ * area of the specification and this sample demonstrates spec compliant methods, as
* well as utility methods that have been added to Tuscany to address issues within
* the specification.
*
@@ -88,97 +94,129 @@
* @see org.apache.tuscany.samples.sdo.specExampleSection.AccessDataObjectsUsingXPath
*/
-public class ObtainingDataGraphFromXml {
-
- /**
- * Execute this method in order to run the sample.
- *
- * @param args
- */
+public class ObtainingDataGraphFromXml extends SampleBase {
+
+
+
+ public ObtainingDataGraphFromXml(int userLevel) {
+ super(userLevel);
+ }
+
public static void main(String[] args) {
- System.out.println("***************************************");
- System.out.println("SDO Sample ObtainingDataGraphFromXml");
- System.out.println("***************************************");
- System.out.println("Demonstrates a vareity of methods available to obtain the root DataObject"
- + " contained within an xml representation of a DataGraph.");
- System.out.println("***************************************");
+
+ /*
+ * Create an instance of the sample program. Edit the "userLevel" argument to suit
+ * your experience, NOVICE, MASTERED_THE_BASICS or ADVANCED
+ */
+ ObtainingDataGraphFromXml sample = new ObtainingDataGraphFromXml(NOVICE);
+ sample.run();
+
+ }
+
+
+ public void run () {
+ banner('*',
+ "SDO Sample " + this.getClass().getName() + "\n\n" +
+
+ "This sample touches an area of the SDO API where the emphasis has changed over the various\n"+
+ "version of the specification, and so it's important to be clear what's going on\n"+
+ "First off lets be sure of our terminology ...\n"+
+ "1) A \"data graph\" is a just collection of DataObjects, all contained within a single\n"+
+ "containment hierarchy, with a single root object, and possibly having some non-containment\n"+
+ "references\n"+
+ "2) A \"DataGraph\" is an instance of the SDO DataGraph class, used as a container for the root\n"+
+ "DataObject of a data graph, and providing a means to access a change summary for the data graph.\n\n"+
+ "More recent versions of the SDO specification have provided alternative means of containment\n"+
+ "of a data graph ...\n"+
+ "3) The graph can be contained in a DataObject of a built-in SDO Type with namespace URI \"commonj.sdo\"\n" +
+ "and name \"DataGraph\": so this is a modeled version of the special DataGraph class.\n"+
+ "4) The Graph can be contained in an XMLDocument instance, which provides for things such as\n"+
+ "naming the root element of an XML instance document"
+ );
+
+ scope = useDefaultScopeForTypes();
+ loadXMLSchemaFromFile(scope, SdoSampleConstants.COMPANY_XSD);
- // define Types
- try {
- System.out.println("Defining Types using XSD");
- InputStream is = null;
- is = ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_XSD);
- XSDHelper.INSTANCE.define(is, null);
- is.close();
- System.out.println("Type definition completed");
- } catch (Exception e) {
- System.out.println("Exception caught defining types " + e.toString());
- e.printStackTrace();
- }
try {
+
+
- /**
- * A DataGraph is an optional envelope for a graph of DataObjects and an
- * associated ChangeSummary.
- *
- * The specification group is currently investigating options regarding
- * obtaining a DataGraph from an xml file as well as the role of the
- * DataGraph within the SDO specification.
- *
- * In order to obtain the rootObject contained within the specification
- * the specification demonstrates reading in an XML file and obtaining a
- * DataObject that represents the datagraph contained within the file.
- * Note, that the specification does not obtain a DataGraph - there are
- * not mechanisms within the specification for obtaining a DataGraph from
- * xml. Obtaining the root DataObject from this datagraph representation
- * is quite cumbersome and is demonstrated below.
- *
- * In order to address this current limitation within the specification
- * Tuscany has added a utility method to SDOUtil that allows a user to
- * obtain an actual DataGraph from xml.
- */
DataObject company = null;
- /**
- * Use specification mechanism for obtaining a DataObject that represents the datagraph
- */
- System.out.println("Using specification methods to obtain DataObject represeenting a datagraph from xml");
-
- // When the xml file represents a DataGraph the root Object
- // of the XMLDocument is a DataGraph
- DataObject dataObjectRepresentingDataGraph = XMLHelper.INSTANCE.load(
- ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML)).getRootObject();
-
- // Obtain the company DataObject from the DataObject representing the datagraph
- company = dataObjectRepresentingDataGraph.getDataObject("company");
+ commentary(INTERMEDIATE,
+ "Here we see the specification's example for obtaining dealing with\n"+
+ "loading a data graph which uses a method, XMLHelper.load(). This loads an XML instance document\n"+
+ "into an instance of XMLDocument ...\n\n"+
+ "XMLDocument doc = scope.getXMLHelper().load(\n"+
+ " ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML));"
+ );
+
+ InputStream is = ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML);
+ int x= is.available();
+ byte b[]= new byte[x];
+ is.read(b);
+ String instanceDoc = new String(b);
+
+ System.out.println(instanceDoc);
- System.out.println("Obtained DataObject representing datagraph");
+ XMLDocument doc = scope.getXMLHelper().load(
+ ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML));
+
+ commentary(INTERMEDIATE,
+ "Now we can get the wrapper for the data graph, which in this case is the DataObject\n"+
+ "of type commonj.sdo#DataGraph. Note how there's no magic here; no special class for\n"+
+ "DataGraph, no special handling, this is just a standard pattern of using a built in SDO Type.\n"+
+ "The wrapper is there purely because it was serialized\n"+
+ "into the XML document, using the standard serialization technique.\n\n" +
+ "DataObject dataObjectRepresentingDataGraph = doc.getRootObject();");
+
+ DataObject dataObjectRepresentingDataGraph = doc.getRootObject();
+
System.out.println(dataObjectRepresentingDataGraph);
- System.out.println("Obtained root DataObject from datagraph");
+
+ commentary(INTERMEDIATE,
+ "If you are confused by the fact that whatt we really get is an instance of DataGraphTypeImpl\n"+
+ "This really is a DataObject, but it is a generated class extending DataObjectImpl\n+"+
+ "representing the DataGraph model.");
+
+ company = dataObjectRepresentingDataGraph.getDataObject("company");
+
+ commentary(INTERMEDIATE,
+ "We've obtained a DataObject representing the data graph, and from that we have obtained\n"+
+ "the true root object of the business data");
+
System.out.println(company);
System.out.println();
-
- /**
- * Use utility method to obtain an actual DataGraph from the xml
- */
+ commentary(INTERMEDIATE,
+ "Using an instance of DataGraph can perhaps be seen as an older style pattern of wrapping a data graph\n"+
+ "and the first approach is likely to get more emphaissi and attention in future revisions of the spec.\n"+
+ "The SDO API has some limitations in the area of saving and loading instances of the\n"+
+ "Java DataGraph type, so Tuscany has an API for doing this ...\n\n"+
+ "DataGraph datagraph = SDOUtil.loadDataGraph(\n"+
+ " ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML), null);"
+
+ );
+
DataGraph datagraph = SDOUtil.loadDataGraph(ClassLoader.getSystemResourceAsStream(SdoSampleConstants.COMPANY_DATAGRAPH_XML), null);
- // Obtain the company DataObject from the actual DataGraph
- company = datagraph.getRootObject();
- System.out.println("Obtained actual DataGraph:");
+
System.out.println(datagraph);
- System.out.println("Obtained root DataObject from DataGraph:");
+
+ commentary(INTERMEDIATE,
+ "In this case we directly receive an instance of DataGraph and can retrieve the root\n"+
+ "business object from the DataGraph\n\n"+
+ "DataObject company = datagraph.getRootObject();");
+
+ company = datagraph.getRootObject();
System.out.println(company);
System.out.println();
} catch (Exception e) {
- System.out.println("Sorry there was an error encountered " + e.toString());
- e.printStackTrace();
+ somethingUnexpectedHasHappened(e);
}
- System.out.println("GoodBye");
}
}
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