svn commit: r1497602 - /maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java

[se...@apache.org]

Author: sebb
Date: Thu Jun 27 22:54:05 2013
New Revision: 1497602

URL: http://svn.apache.org/r1497602
Log:
Configure pluginId from plugin.xml

Modified:
    maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java

Modified: maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java
URL: http://svn.apache.org/viewvc/maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java?rev=1497602&r1=1497601&r2=1497602&view=diff
==============================================================================
--- maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java (original)
+++ maven/sandbox/trunk/plugins/maven-digest-plugin/src/main/java/org/apache/maven/plugins/digest/HelperMojo.java Thu Jun 27 22:54:05 2013
@@ -18,11 +18,23 @@
 
 package org.apache.maven.plugins.digest;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.parsers.ParserConfigurationException;
 
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugins.annotations.Mojo;
 import org.apache.maven.plugins.help.DescribeMojo;
+import org.w3c.dom.Document;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
+import org.xml.sax.SAXException;
 
 /**
  * Helper Mojo that extends the standard Maven help plugin describe goal. This is needed because the generated help mojo
@@ -32,6 +44,8 @@ import org.apache.maven.plugins.help.Des
 public class HelperMojo
     extends DescribeMojo
 {
+    // Where to find plugin config
+    private static final String PLUGIN_PATH = "/META-INF/maven/plugin.xml";
 
     // ----------------------------------------------------------------------
     // Mojo components
@@ -56,6 +70,7 @@ public class HelperMojo
     public void execute()
         throws MojoExecutionException
     {
+        final String pluginId = getpluginGA();
         Field f = null;
         boolean isAccessible = true; // assume accessible
         try
@@ -67,11 +82,7 @@ public class HelperMojo
             {
                 f.setAccessible( true );
             }
-            // N.B. Customise for each plugin
-            // We used to use project component to get the info, but that forces plugin to be used in a project
-            // Plugin should be able to be used standalone
-            final String plugin = "org.apache.maven.plugins:maven-digest-plugin";
-            f.set( this, plugin );
+            f.set( this, pluginId );
             super.execute();
         }
         catch ( Exception e )
@@ -93,6 +104,81 @@ public class HelperMojo
     // ----------------------------------------------------------------------
     // Private methods
     // ----------------------------------------------------------------------
+    private String getpluginGA() throws MojoExecutionException {
+        Document doc = build();
+        Node plugin = getSingleChild( doc, "plugin" );
+        String id = getValue( plugin, "groupId" ) + ":" + getValue( plugin, "artifactId" );
+        return id;
+    }
+
+    private Document build()
+        throws MojoExecutionException
+    {
+        getLog().debug( "load plugin-help.xml: " + PLUGIN_PATH );
+        InputStream is = getClass().getResourceAsStream( PLUGIN_PATH );
+        try
+        {
+            DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
+            DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
+            return dBuilder.parse( is );
+        }
+        catch ( IOException e )
+        {
+            throw new MojoExecutionException( e.getMessage(), e );
+        }
+        catch ( ParserConfigurationException e )
+        {
+            throw new MojoExecutionException( e.getMessage(), e );
+        }
+        catch ( SAXException e )
+        {
+            throw new MojoExecutionException( e.getMessage(), e );
+        }
+        finally
+        {
+            try {
+                is.close();
+            } catch (IOException e) {
+            }
+        }
+    }
+
+    private List<Node> findNamedChild( Node node, String elementName )
+    {
+        List<Node> result = new ArrayList<Node>();
+        NodeList childNodes = node.getChildNodes();
+        for ( int i = 0; i < childNodes.getLength(); i++ )
+        {
+            Node item = childNodes.item( i );
+            if ( elementName.equals( item.getNodeName() ) )
+            {
+                result.add( item );
+            }
+        }
+        return result;
+    }
+
+    private Node getSingleChild( Node node, String elementName )
+        throws MojoExecutionException
+    {
+        List<Node> namedChild = findNamedChild( node, elementName );
+        if ( namedChild.isEmpty() )
+        {
+            throw new MojoExecutionException( "Could not find " + elementName + " in plugin-help.xml" );
+        }
+        if ( namedChild.size() > 1 )
+        {
+            throw new MojoExecutionException( "Multiple " + elementName + " in plugin-help.xml" );
+        }
+        return namedChild.get( 0 );
+    }
+
+    private String getValue( Node node, String elementName )
+        throws MojoExecutionException
+    {
+        return getSingleChild( node, elementName ).getTextContent();
+    }
+
 
     // ----------------------------------------------------------------------
     // Static methods