Author: rgoers
Date: Mon Mar 30 23:00:32 2009
New Revision: 760225
URL: http://svn.apache.org/viewvc?rev=760225&view=rev
Log:
CONFIGURATION-378 Add MergeCombiner
Added:
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/MergeCombiner.java
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/tree/TestMergeCombiner.java
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/NodeCombiner.java
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/TestDefaultConfigurationBuilder.java
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testMultiTenentConfigurationBuilder.xml
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine1.xml
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine2.xml
commons/proper/configuration/branches/configuration2_experimental/xdocs/changes.xml
commons/proper/configuration/branches/configuration2_experimental/xdocs/userguide/howto_combinedconfiguration.xml
Added:
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/MergeCombiner.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/MergeCombiner.java?rev=760225&view=auto
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/MergeCombiner.java
(added)
+++
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/MergeCombiner.java
Mon Mar 30 23:00:32 2009
@@ -0,0 +1,172 @@
+/*
+ * 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.commons.configuration2.tree;
+
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ArrayList;
+
+/**
+ * <p>
+ * A specialized implementation of the <code>NodeCombiner</code> interface
+ * that performs a merge from two passed in node hierarchies.
+ * </p>
+ * <p>
+ * This combiner performs the merge using a few rules:
+ * <ol>
+ * <li>Nodes can be merged when attributes that appear in both have the same
value.</li>
+ * <li>Only a single node in the second file is considered a match to the node
in the first file.</li>
+ * <li>Attributes in nodes that match are merged.
+ * <li>Nodes in both files that do not match are added to the result.</li>
+ * </ol>
+ * </p>
+ *
+ * @author <a
+ * href="http://commons.apache.org/configuration/team-list.html";>Commons
+ * Configuration team</a>
+ * @version $Id: $
+ * @since 1.7
+ */
+public class MergeCombiner extends NodeCombiner
+{
+ /**
+ * Combines the given nodes to a new union node.
+ *
+ * @param node1 the first source node
+ * @param node2 the second source node
+ * @return the union node
+ */
+
+ public ConfigurationNode combine(ConfigurationNode node1,
ConfigurationNode node2)
+ {
+ ConfigurationNode result = doCombine(node1, node2);
+ printTree(result);
+ return result;
+ }
+
+ public ConfigurationNode doCombine(ConfigurationNode node1,
ConfigurationNode node2)
+ {
+ ViewNode result = createViewNode();
+ result.setName(node1.getName());
+ result.setValue(node1.getValue());
+ addAttributes(result, node1, node2);
+
+ // Check if nodes can be combined
+ List children2 = new LinkedList(node2.getChildren());
+ for (Iterator it = node1.getChildren().iterator(); it.hasNext();)
+ {
+ ConfigurationNode child1 = (ConfigurationNode) it.next();
+ ConfigurationNode child2 = canCombine(node1, node2, child1,
children2);
+ if (child2 != null)
+ {
+ result.addChild(doCombine(child1, child2));
+ children2.remove(child2);
+ }
+ else
+ {
+ result.addChild(child1);
+ }
+ }
+
+ // Add remaining children of node 2
+ for (Iterator it = children2.iterator(); it.hasNext();)
+ {
+ result.addChild((ConfigurationNode) it.next());
+ }
+ return result;
+ }
+
+ /**
+ * Handles the attributes during a combination process. First all
attributes
+ * of the first node will be added to the result. Then all attributes of
the
+ * second node, which are not contained in the first node, will also be
+ * added.
+ *
+ * @param result the resulting node
+ * @param node1 the first node
+ * @param node2 the second node
+ */
+ protected void addAttributes(ViewNode result, ConfigurationNode node1,
+ ConfigurationNode node2)
+ {
+ result.appendAttributes(node1);
+ for (Iterator it = node2.getAttributes().iterator(); it.hasNext();)
+ {
+ ConfigurationNode attr = (ConfigurationNode) it.next();
+ if (node1.getAttributeCount(attr.getName()) == 0)
+ {
+ result.addAttribute(attr);
+ }
+ }
+ }
+
+ /**
+ * Tests if the first node can be combined with the second node. A node can
+ * only be combined if its attributes are all present in the second node
and
+ * they all have the same value.
+ *
+ * @param node1 the first node
+ * @param node2 the second node
+ * @param child the child node (of the first node)
+ * @return a child of the second node, with which a combination is possible
+ */
+ protected ConfigurationNode canCombine(ConfigurationNode node1,
+ ConfigurationNode node2, ConfigurationNode child, List children2)
+ {
+ List attrs1 = child.getAttributes();
+ List nodes = new ArrayList();
+
+ List children = node2.getChildren(child.getName());
+ Iterator it = children.iterator();
+ while (it.hasNext())
+ {
+ ConfigurationNode node = (ConfigurationNode) it.next();
+ Iterator iter = attrs1.iterator();
+ while (iter.hasNext())
+ {
+ ConfigurationNode attr1 = (ConfigurationNode) iter.next();
+ List list2 = node.getAttributes(attr1.getName());
+ if (list2.size() == 1
+ &&
!attr1.getValue().equals(((ConfigurationNode)list2.get(0)).getValue()))
+ {
+ node = null;
+ break;
+ }
+ }
+ if (node != null)
+ {
+ nodes.add(node);
+ }
+ }
+
+ if (nodes.size() == 1)
+ {
+ return (ConfigurationNode) nodes.get(0);
+ }
+ if (nodes.size() > 1 && !isListNode(child))
+ {
+ Iterator iter = nodes.iterator();
+ while (iter.hasNext())
+ {
+ children2.remove(iter.next());
+ }
+ }
+
+ return null;
+ }
+}
\ No newline at end of file
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/NodeCombiner.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/NodeCombiner.java?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/NodeCombiner.java
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/src/main/java/org/apache/commons/configuration2/tree/NodeCombiner.java
Mon Mar 30 23:00:32 2009
@@ -20,6 +20,8 @@
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
+import java.util.List;
+import java.io.PrintStream;
/**
* <p>
@@ -51,6 +53,9 @@
*/
public abstract class NodeCombiner
{
+ /** Stream to write debug output to */
+ private PrintStream debugStream = null;
+
/** Stores a list with node names that are known to be list nodes. */
protected Set<String> listNodes;
@@ -119,4 +124,51 @@
{
return new ViewNode();
}
+
+ /**
+ * Set the output stream to write the tree to.
+ * @param stream The OutputStream.
+ */
+ public void setDebugStream(PrintStream stream)
+ {
+ this.debugStream = stream;
+ }
+
+ protected void printTree(ConfigurationNode result)
+ {
+ if (debugStream != null)
+ {
+ printTree("", result);
+ }
+ }
+
+ private void printTree(String indent, ConfigurationNode result)
+ {
+ StringBuffer buffer = new
StringBuffer(indent).append("<").append(result.getName());
+ for (ConfigurationNode node : result.getAttributes())
+ {
+ buffer.append("
").append(node.getName()).append("='").append(node.getValue()).append("'");
+ }
+ buffer.append(">");
+ debugStream.print(buffer.toString());
+ if (result.getValue() != null)
+ {
+ debugStream.print(result.getValue());
+ }
+ boolean newline = false;
+ if (result.getChildrenCount() > 0)
+ {
+ debugStream.print("\n");
+ for (ConfigurationNode node : result.getChildren())
+ {
+ printTree(indent + " ", node);
+ }
+ newline = true;
+ }
+ if (newline)
+ {
+ debugStream.print(indent);
+ }
+ debugStream.println("</" + result.getName() + ">");
+ }
}
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/TestDefaultConfigurationBuilder.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/TestDefaultConfigurationBuilder.java?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/TestDefaultConfigurationBuilder.java
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/TestDefaultConfigurationBuilder.java
Mon Mar 30 23:00:32 2009
@@ -880,10 +880,6 @@
verify("1005", config, 50);
}
- /** This test doesn't pass and rightfully so. A new "MergeCombiner" needs
to be
- * created so it will.
- * @throws Exception
- */ /*
public void testMultiTenantConfigurationAt() throws Exception
{
factory.setFile(MULTI_TENENT_FILE);
@@ -895,7 +891,7 @@
HierarchicalConfiguration sub2 =
config.configurationAt("Channels/chann...@id='2']");
assertEquals("Channel 2", sub2.getString("Name"));
assertEquals("more test 2 data", sub2.getString("MoreChannelData"));
- } */
+ }
public void testMerge() throws Exception
{
Added:
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/tree/TestMergeCombiner.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/tree/TestMergeCombiner.java?rev=760225&view=auto
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/tree/TestMergeCombiner.java
(added)
+++
commons/proper/configuration/branches/configuration2_experimental/src/test/java/org/apache/commons/configuration2/tree/TestMergeCombiner.java
Mon Mar 30 23:00:32 2009
@@ -0,0 +1,172 @@
+/*
+ * 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.commons.configuration2.tree;
+
+import java.util.List;
+
+import org.apache.commons.configuration2.ConfigurationException;
+import org.apache.commons.configuration2.HierarchicalConfiguration;
+import org.apache.commons.configuration2.XMLConfiguration;
+import org.apache.commons.configuration2.tree.xpath.XPathExpressionEngine;
+
+/**
+ * Test class for MergeCombiner.
+ *
+ * @version $Id: $
+ */
+public class TestMergeCombiner extends AbstractCombinerTest
+{
+ /**
+ * Creates the combiner.
+ *
+ * @return the combiner
+ */
+ protected NodeCombiner createCombiner()
+ {
+ return new MergeCombiner();
+ }
+
+ /**
+ * Tests combination of simple elements.
+ */
+ public void testSimpleValues() throws ConfigurationException
+ {
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ assertEquals("Wrong number of bgcolors", 0, config
+ .getMaxIndex("gui.bgcolor"));
+ assertEquals("Wrong bgcolor", "green",
config.getString("gui.bgcolor"));
+ assertEquals("Wrong selcolor", "yellow", config
+ .getString("gui.selcolor"));
+ assertEquals("Wrong fgcolor", "blue", config.getString("gui.fgcolor"));
+ assertEquals("Wrong level", 1, config.getInt("gui.level"));
+ }
+
+ /**
+ * Tests combination of attributes.
+ */
+ public void testAttributes() throws ConfigurationException
+ {
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ assertEquals("Wrong value of min attribute", 1, config
+ .getInt("gui.lev...@min]"));
+ assertEquals("Wrong value of default attribute", 2, config
+ .getInt("gui.lev...@default]"));
+ assertEquals("Wrong number of id attributes", 0, config
+ .getMaxIndex("database.tables.table(0)[...@id]"));
+ assertEquals("Wrong value of table id", 1, config
+ .getInt("database.tables.table(0)[...@id]"));
+ }
+
+ /**
+ * Tests whether property values are correctly overridden.
+ */
+ public void testOverrideValues() throws ConfigurationException
+ {
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ assertEquals("Wrong user", "Admin", config
+ .getString("base.services.security.login.user"));
+ assertEquals("Wrong user type", "default", config
+ .getString("base.services.security.login.us...@type]"));
+ assertNull("Wrong password",
config.getString("base.services.security.login.passwd"));
+ assertEquals("Wrong password type", "secret", config
+ .getString("base.services.security.login.pass...@type]"));
+ }
+
+ /**
+ * Tests if a list from the first node structure overrides a list in the
+ * second structure.
+ */
+ public void testListFromFirstStructure() throws ConfigurationException
+ {
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ assertEquals("Wrong number of services", 0, config
+ .getMaxIndex("net.service.url"));
+ assertEquals("Wrong service", "http://service1.org";, config
+ .getString("net.service.url"));
+ assertFalse("Type attribute available", config
+ .containsKey("net.service.u...@type]"));
+ }
+
+ /**
+ * Tests if a list from the second structure is added if it is not defined
+ * in the first structure.
+ */
+ public void testListFromSecondStructure() throws ConfigurationException
+ {
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ assertEquals("Wrong number of servers", 3, config
+ .getMaxIndex("net.server.url"));
+ assertEquals("Wrong server", "http://testsvr.com";, config
+ .getString("net.server.url(2)"));
+ }
+
+ /**
+ * Tests the combination of the table structure. With the merge combiner
+ * both table 1 and table 2 should be present.
+ */
+ public void testCombinedTable() throws ConfigurationException
+ {
+ checkTable(createCombinedConfiguration());
+ }
+
+ public void testMerge() throws ConfigurationException
+ {
+ //combiner.setDebugStream(System.out);
+ HierarchicalConfiguration config = createCombinedConfiguration();
+ config.setExpressionEngine(new XPathExpressionEngine());
+ assertEquals("Wrong number of Channels", 3,
config.getMaxIndex("Channels/Channel"));
+ assertEquals("Bad Channel 1 Name", "My Channel",
+ config.getString("Channels/chann...@id='1']/Name"));
+ assertEquals("Bad Channel Type", "half",
+ config.getString("Channels/chann...@id='1']/@type"));
+ assertEquals("Bad Channel 2 Name", "Channel 2",
+ config.getString("Channels/chann...@id='2']/Name"));
+ assertEquals("Bad Channel Type", "full",
+ config.getString("Channels/chann...@id='2']/@type"));
+ assertEquals("Bad Channel Data", "test 1 data",
+ config.getString("Channels/chann...@id='1']/ChannelData"));
+ assertEquals("Bad Channel Data", "test 2 data",
+ config.getString("Channels/chann...@id='2']/ChannelData"));
+ assertEquals("Bad Channel Data", "more test 2 data",
+ config.getString("Channels/chann...@id='2']/MoreChannelData"));
+
+ }
+
+ /**
+ * Helper method for checking the combined table structure.
+ *
+ * @param config the config
+ * @return the node for the table element
+ */
+ private ConfigurationNode checkTable(HierarchicalConfiguration config)
+ {
+ assertEquals("Wrong number of tables", 1, config
+ .getMaxIndex("database.tables.table"));
+ HierarchicalConfiguration c = config
+ .configurationAt("database.tables.table(0)");
+ assertEquals("Wrong table name", "documents", c.getString("name"));
+ assertEquals("Wrong number of fields", 2, c
+ .getMaxIndex("fields.field.name"));
+ assertEquals("Wrong field", "docname", c
+ .getString("fields.field(1).name"));
+
+ List nds = config.getExpressionEngine().query(config.getRootNode(),
+ "database.tables.table");
+ assertFalse("No node found", nds.isEmpty());
+ return (ConfigurationNode) nds.get(0);
+ }
+}
\ No newline at end of file
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testMultiTenentConfigurationBuilder.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testMultiTenentConfigurationBuilder.xml?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testMultiTenentConfigurationBuilder.xml
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testMultiTenentConfigurationBuilder.xml
Mon Mar 30 23:00:32 2009
@@ -5,6 +5,7 @@
<result delimiterParsingDisabled="true" forceReloadCheck="true"
config-class="org.apache.commons.configuration2.DynamicCombinedConfiguration"
keyPattern="$${sys:Id}">
+ <nodeCombiner
config-class="org.apache.commons.configuration2.tree.MergeCombiner"/>
<expressionEngine
config-class="org.apache.commons.configuration2.tree.xpath.XPathExpressionEngine"/>
</result>
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine1.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine1.xml?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine1.xml
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine1.xml
Mon Mar 30 23:00:32 2009
@@ -49,4 +49,15 @@
</table>
</tables>
</database>
+ <Channels>
+ <Channel id="1" type="half">
+ <Name>My Channel</Name>
+ </Channel>
+ <Channel id="2">
+ <MoreChannelData>more test 2 data</MoreChannelData>
+ </Channel>
+ <Channel id="3" type="half">
+ <Name>Test Channel</Name>
+ </Channel>
+ </Channels>
</config>
Modified:
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine2.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine2.xml?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine2.xml
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/src/test/resources/testcombine2.xml
Mon Mar 30 23:00:32 2009
@@ -45,4 +45,18 @@
</table>
</tables>
</database>
+ <Channels>
+ <Channel id="1">
+ <Name>Channel 1</Name>
+ <ChannelData>test 1 data</ChannelData>
+ </Channel>
+ <Channel id="2" type="full">
+ <Name>Channel 2</Name>
+ <ChannelData>test 2 data</ChannelData>
+ </Channel>
+ <Channel id="3" type="full">
+ <Name>Channel 3</Name>
+ <ChannelData>test 3 data</ChannelData>
+ </Channel>
+ </Channels>
</config>
Modified:
commons/proper/configuration/branches/configuration2_experimental/xdocs/changes.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/xdocs/changes.xml?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/xdocs/changes.xml
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/xdocs/changes.xml
Mon Mar 30 23:00:32 2009
@@ -85,6 +85,10 @@
</release>
<release version="1.7" date="in SVN" description="">
+ <action dev="rgoers" type="add" issue="CONFIGURATION-378">
+ Added MergeCombiner to allow elements in two configurations to be
merged when the
+ element and attributes in the first file match those in the second
file.
+ </action>
<action dev="rgoers" type="add" issue="CONFIGURATION-340">
File system access has been abstracted to a FileSystem interface. Two
implementations
are provided, DefaultFileSystem that behaves in a backward compatible
manner and
Modified:
commons/proper/configuration/branches/configuration2_experimental/xdocs/userguide/howto_combinedconfiguration.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/configuration2_experimental/xdocs/userguide/howto_combinedconfiguration.xml?rev=760225&r1=760224&r2=760225&view=diff
==============================================================================
---
commons/proper/configuration/branches/configuration2_experimental/xdocs/userguide/howto_combinedconfiguration.xml
(original)
+++
commons/proper/configuration/branches/configuration2_experimental/xdocs/userguide/howto_combinedconfiguration.xml
Mon Mar 30 23:00:32 2009
@@ -85,10 +85,11 @@
takes the root nodes of two hierarchical configurations and returns the
root node of the combined node structure. It is up to a concrete
implementation how this combined structure will look like. Commons
- Configuration ships with the two concrete implementations
- <code><a
href="../apidocs/org/apache/commons/configuration2/tree/OverrideCombiner.html">OverrideCombiner</a></code>
+ Configuration ships with three concrete implementations
+ <code><a
href="../apidocs/org/apache/commons/configuration2/tree/OverrideCombiner.html">OverrideCombiner</a></code>,
+ <code><a
href="../apidocs/org/apache/commons/configuration/tree/MergeCombiner.html">MergeCombiner</a></code>
and <code><a
href="../apidocs/org/apache/commons/configuration2/tree/UnionCombiner.html">UnionCombiner</a></code>,
- which implement an override and a union semantics respective.
+ which implement an override, merge and union semantics respectively.
</p>
<p>
Constructing a combination of multiple node hierarchies is not a trivial
@@ -216,6 +217,471 @@
node combiner would have concluded itself that <code>table</code> is a
list
node and would have acted correspondigly.
</p>
+ <p>
+ The examples the follow are provided to further illustrate the
differences
+ between the combiners that are delivered with Commons Configuration. The
first
+ two files are the files that will be combined.
+ </p>
+ <table border='0'>
+ <tr>
+ <th width="50%">testfile1.xml</th>
+ <th width="50%">testfile2.xml</th>
+ </tr>
+ <tr><td width="50%">
+<source><![CDATA[<config>
+ <gui>
+ <bgcolor>green</bgcolor>
+ <selcolor>yellow</selcolor>
+ <level default="2">1</level>
+ </gui>
+ <net>
+ <proxy>
+ <url>http://www.url1.org</url>
+ <url>http://www.url2.org</url>
+ <url>http://www.url3.org</url>
+ </proxy>
+ <service>
+ <url>http://service1.org</url>
+ </service>
+ <server>
+ </server>
+ </net>
+ <base>
+ <services>
+ <security>
+ <login>
+ <user>Admin</user>
+ <passwd type="secret"/>
+ </login>
+ </security>
+ </services>
+ </base>
+ <database>
+ <tables>
+ <table id="1">
+ <name>documents</name>
+ <fields>
+ <field>
+ <name>docid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>docname</name>
+ <type>varchar</type>
+ </field>
+ <field>
+ <name>authorID</name>
+ <type>int</type>
+ </field>
+ </fields>
+ </table>
+ </tables>
+ </database>
+ <Channels>
+ <Channel id="1" type="half">
+ <Name>My Channel</Name>
+ </Channel>
+ <Channel id="2">
+ <MoreChannelData>more test 2 data</MoreChannelData>
+ </Channel>
+ <Channel id="3" type="half">
+ <Name>Test Channel</Name>
+ </Channel>
+ <Channel id="4">
+ <Name>Channel 4</Name>
+ </Channel>
+ </Channels>
+</config>
+]]></source></td><td width="50%">
+<source><![CDATA[<config>
+ <base>
+ <services>
+ <security>
+ <login>
+ <user type="default">scotty</user>
+ <passwd>BeamMeUp</passwd>
+ </login>
+ </security>
+ </services>
+ </base>
+ <gui>
+ <bgcolor>black</bgcolor>
+ <fgcolor>blue</fgcolor>
+ <level min="1">4</level>
+ </gui>
+ <net>
+ <server>
+ <url>http://appsvr1.com</url>
+ <url>http://appsvr2.com</url>
+ <url>http://testsvr.com</url>
+ <url>http://backupsvr.com</url>
+ </server>
+ <service>
+ <url type="2">http://service2.org</url>
+ <url type="2">http://service3.org</url>
+ </service>
+ </net>
+ <database>
+ <tables>
+ <table id="2">
+ <name>tasks</name>
+ <fields>
+ <field>
+ <name>taskid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>taskname</name>
+ <type>varchar</type>
+ </field>
+ </fields>
+ </table>
+ </tables>
+ </database>
+ <Channels>
+ <Channel id="1">
+ <Name>Channel 1</Name>
+ <ChannelData>test 1 data</ChannelData>
+ </Channel>
+ <Channel id="2" type="full">
+ <Name>Channel 2</Name>
+ <ChannelData>test 2 data</ChannelData>
+ </Channel>
+ <Channel id="3" type="full">
+ <Name>Channel 3</Name>
+ <ChannelData>test 3 data</ChannelData>
+ </Channel>
+ <Channel id="4" type="half">
+ <Name>Test Channel 1</Name>
+ </Channel>
+ <Channel id="4" type="full">
+ <Name>Test Channel 2</Name>
+ </Channel>
+ </Channels>
+</config>
+]]></source></td></tr></table>
+ <p>
+ The first listing shows the result of using the
<code>OverrideCombiner</code>.
+ </p>
+ <table>
+ <tr><th width="40%">OverrideCombiner Results</th><th
width="60%">Notes</th></tr>
+ <tr><td width="40%">
+ <source><![CDATA[<config>
+ <gui>
+ <bgcolor>green</bgcolor>
+ <selcolor>yellow</selcolor>
+ <level default='2' min='1'>1</level>
+ <fgcolor>blue</fgcolor>
+ </gui>
+ <net>
+ <proxy>
+ <url>http://www.url1.org</url>
+ <url>http://www.url2.org</url>
+ <url>http://www.url3.org</url>
+ </proxy>
+ <service>
+ <url>http://service1.org</url>
+ </service>
+ <server>
+ <url>http://appsvr1.com</url>
+ <url>http://appsvr2.com</url>
+ <url>http://testsvr.com</url>
+ <url>http://backupsvr.com</url>
+ </server>
+ </net>
+ <base>
+ <services>
+ <security>
+ <login>
+ <user type='default'>Admin</user>
+ <passwd type='secret'>BeamMeUp</passwd>
+ </login>
+ </security>
+ </services>
+ </base>
+ <database>
+ <tables>
+ <table id='1'>
+ <name>documents</name>
+ <fields>
+ <field>
+ <name>docid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>docname</name>
+ <type>varchar</type>
+ </field>
+ <field>
+ <name>authorID</name>
+ <type>int</type>
+ </field>
+ </fields>
+ </table>
+ </tables>
+ </database>
+ <Channels>
+ <Channel id='1' type='half'>
+ <Name>My Channel</Name>
+ </Channel>
+ <Channel id='2'>
+ <MoreChannelData>more test 2 data</MoreChannelData>
+ </Channel>
+ <Channel id='3' type='half'>
+ <Name>Test Channel</Name>
+ </Channel>
+ </Channels>
+</config>
+]]></source></td><td width="60%">
+ <p>
+ The features that are significant in this file are:
+ <ul>
+ <li>In the gui section each of the child elements only appears once.
The level element
+ merges the attributes from the two files and uses the element value
of the first file.</li>
+ <li>In the security section the user type attribute was obtained
from the second file
+ while the user value came from the first file. Alternately, the
password type was
+ obtained from the first file while the value came from the
second.</li>
+ <li>Only the data from table 1 was included.</li>
+ <li>Channel 1 in the first file completely overrode Channel 1 in the
second file.</li>
+ <li>Channel 2 in the first file completely overrode Channel 2 in the
second file. While
+ the attributes were merged in the case of the login elements the
type attribute
+ was not merged in this case.</li>
+ <li>Again, only Channel 3 from the first file was included.</li>
+ </ul>
+ </p>
+ <p>
+ How the Channel elements ended up may not at first be obvious. The
<code>OverrideCombiner</code>
+ simply noticed that the Channels element had three child elements
named Channel and
+ used that to determine that only the contents of the Channels element
in the first file
+ would be used.
+ </p></td></tr></table>
+ <p>
+ The next file is the the result of using the <code>UnionCombiner</code>
+ </p>
+ <table>
+ <tr>
+ <th width="40%">UnionCombiner Results</th>
+ <th width="60%">Notes</th>
+ </tr>
+ <tr><td width="40%">
+ <source><![CDATA[<config>
+ <gui>
+ <bgcolor>green</bgcolor>
+ <selcolor>yellow</selcolor>
+ <level default='2'>1</level>
+ <bgcolor>black</bgcolor>
+ <fgcolor>blue</fgcolor>
+ <level min='1'>4</level>
+ </gui>
+ <net>
+ <proxy>
+ <url>http://www.url1.org</url>
+ <url>http://www.url2.org</url>
+ <url>http://www.url3.org</url>
+ </proxy>
+ <service>
+ <url>http://service1.org</url>
+ <url type='2'>http://service2.org</url>
+ <url type='2'>http://service3.org</url>
+ </service>
+ <server></server>
+ <server>
+ <url>http://appsvr1.com</url>
+ <url>http://appsvr2.com</url>
+ <url>http://testsvr.com</url>
+ <url>http://backupsvr.com</url>
+ </server>
+ </net>
+ <base>
+ <services>
+ <security>
+ <login>
+ <user>Admin</user>
+ <passwd type='secret'></passwd>
+ <user type='default'>scotty</user>
+ <passwd>BeamMeUp</passwd>
+ </login>
+ </security>
+ </services>
+ </base>
+ <database>
+ <tables>
+ <table id='1' id='2'>
+ <name>documents</name>
+ <fields>
+ <field>
+ <name>docid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>docname</name>
+ <type>varchar</type>
+ </field>
+ <field>
+ <name>authorID</name>
+ <type>int</type>
+ </field>
+ <field>
+ <name>taskid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>taskname</name>
+ <type>varchar</type>
+ </field>
+ </fields>
+ <name>tasks</name>
+ </table>
+ </tables>
+ </database>
+ <Channels>
+ <Channel id='1' type='half'>
+ <Name>My Channel</Name>
+ </Channel>
+ <Channel id='2'>
+ <MoreChannelData>more test 2 data</MoreChannelData>
+ </Channel>
+ <Channel id='3' type='half'>
+ <Name>Test Channel</Name>
+ </Channel>
+ <Channel id='1'>
+ <Name>Channel 1</Name>
+ <ChannelData>test 1 data</ChannelData>
+ </Channel>
+ <Channel id='2' type='full'>
+ <Name>Channel 2</Name>
+ <ChannelData>test 2 data</ChannelData>
+ </Channel>
+ <Channel id='3' type='full'>
+ <Name>Channel 3</Name>
+ <ChannelData>test 3 data</ChannelData>
+ </Channel>
+ </Channels>
+</config>
+]]></source></td><td width="60%">
+ <p>
+ The feature that is significant in this file is rather obvious. It is
just a simple
+ union of the contents of the two files.
+ </p>
+ </td></tr></table>
+ <p>
+ Finally, the last file is the result of using the
<code>MergeCombiner</code>
+ </p>
+ <table>
+ <tr>
+ <th width="40%">MergeCombiner Results</th>
+ <th width="60%">Notes</th>
+ </tr>
+ <tr><td width="40%">
+<source><![CDATA[<config>
+ <gui>
+ <bgcolor>green</bgcolor>
+ <selcolor>yellow</selcolor>
+ <level default='2' min='1'>1</level>
+ <fgcolor>blue</fgcolor>
+ </gui>
+ <net>
+ <proxy>
+ <url>http://www.url1.org</url>
+ <url>http://www.url2.org</url>
+ <url>http://www.url3.org</url>
+ </proxy>
+ <service>
+ <url>http://service1.org</url>
+ </service>
+ <server>
+ <url>http://appsvr1.com</url>
+ <url>http://appsvr2.com</url>
+ <url>http://testsvr.com</url>
+ <url>http://backupsvr.com</url>
+ </server>
+ </net>
+ <base>
+ <services>
+ <security>
+ <login>
+ <user type='default'>Admin</user>
+ <passwd type='secret'></passwd>
+ </login>
+ </security>
+ </services>
+ </base>
+ <database>
+ <tables>
+ <table id='1'>
+ <name>documents</name>
+ <fields>
+ <field>
+ <name>docid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>docname</name>
+ <type>varchar</type>
+ </field>
+ <field>
+ <name>authorID</name>
+ <type>int</type>
+ </field>
+ </fields>
+ </table>
+ <table id='2'>
+ <name>tasks</name>
+ <fields>
+ <field>
+ <name>taskid</name>
+ <type>long</type>
+ </field>
+ <field>
+ <name>taskname</name>
+ <type>varchar</type>
+ </field>
+ </fields>
+ </table>
+ </tables>
+ </database>
+ <Channels>
+ <Channel id='1' type='half'>
+ <Name>My Channel</Name>
+ <ChannelData>test 1 data</ChannelData>
+ </Channel>
+ <Channel id='2' type='full'>
+ <MoreChannelData>more test 2 data</MoreChannelData>
+ <Name>Channel 2</Name>
+ <ChannelData>test 2 data</ChannelData>
+ </Channel>
+ <Channel id='3' type='half'>
+ <Name>Test Channel</Name>
+ </Channel>
+ <Channel id='3' type='full'>
+ <Name>Channel 3</Name>
+ <ChannelData>test 3 data</ChannelData>
+ </Channel>
+ </Channels>
+</config>
+]]></source></td><td width="60%">
+ <p>
+ The features that are significant in this file are:
+ <ul>
+ <li>In the gui section the elements were merged.</li>
+ <li>In the net section the elements were merged, with the exception
of the urls.</li>
+ <li>In the security section the user and password were merged.
Notice that the
+ empty value for the password from the first file overrode the
password in the
+ second file.</li>
+ <li>Both table elements appear</li>
+ <li>Channel 1 and Channel 2 were merged</li>
+ <li>Both Channel 3 elements appear as they were determined to not be
the same.</li>
+ </ul>
+ </p>
+ <p>
+ When merging elements attributes play a critical role. If an element
has an attribute that
+ appears in both sources, the value of that attribute must be the same
for the elements to be
+ merged. Merging is only allowed between a single node in each of the
files, so if an element
+ in the first file matches more than one element in the second file no
merging will take
+ place and the element from the first file (and its contents) are
included and the elements
+ in the second file are not. If the element is marked as a list node
then the elements from
+ the second file will also be included.
+ </p></td></tr></table>
</subsection>
<subsection name="Constructing a CombinedConfiguration">
