MTOMCAT-100

Index: tomcat6-maven-plugin/src/main/java/org/apache/tomcat/maven/plugin/tomcat6/AbstractRunMojo.java
===================================================================
--- tomcat6-maven-plugin/src/main/java/org/apache/tomcat/maven/plugin/tomcat6/AbstractRunMojo.java  (revision 1345248)
+++ tomcat6-maven-plugin/src/main/java/org/apache/tomcat/maven/plugin/tomcat6/AbstractRunMojo.java  (working copy)
@@ -60,13 +60,14 @@
 import java.net.InetAddress;
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.security.Principal;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Hashtable;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import org.apache.naming.resources.FileDirContext;

 /**
  * Abstract goal that provides common configuration for embedded Tomcat goals.
@@ -433,6 +434,7 @@
      *
      * @return the webapp context path
      */
+    @Override
     protected String getPath()
     {
         return path;
@@ -465,6 +467,12 @@
             webappLoader.setLoaderClass( classLoaderClass );
         }

+        MultipleDirContext dc = this.getFileDirContext();
+        if (dc != null)
+        {
+            context.setResources(dc);
+        }
+
         context.setLoader( webappLoader );
         File contextFile = getContextFile();
         if ( contextFile != null )
@@ -615,7 +623,7 @@
                 {
                     throw new MojoExecutionException( " tomcatWebXml " + tomcatWebXml.getPath() + " not exists" );
                 }
-                //MTOMCAT-42  here it's a real file resources not a one coming with the mojo
+                //MTOMCAT-42  here it's a real file resources not a one coming with the mojo
                 FileUtils.copyFile( tomcatWebXml, new File( confDir, "web.xml" ) );
                 //copyFile( tomcatWebXml.getPath(), new File( confDir, "web.xml" ) );
             }
@@ -1003,4 +1011,122 @@
             host.addChild( staticContext );
         }
     }
+
+    /**
+     * Scan ${project.build.dir}/apache-tomcat-maven-plugin for directories. Every directory found
+     * is assumed to be a WAR overlay and is added to a MultipleDirContext
+     *
+     * @return
+     */
+    private MultipleDirContext getFileDirContext()
+    {
+        MultipleDirContext ret = null;
+
+        File f = new File(project.getBuild().getDirectory(), "apache-tomcat-maven-plugin");
+        if (f.isDirectory())
+        {
+            ret = new MultipleDirContext();
+            for (final File overlayRoot : f.listFiles())
+            {
+                if (overlayRoot.isDirectory())
+                {
+                    ret.addVirtualDocBase(overlayRoot.getPath());
+                }
+            }
+        }
+
+        return ret;
+    }
+
+    /**
+     * WAR overlays can contain other resources besides classes. This class overlays the extracted
+     * WAR overlay directory over the docBase; if a file is not found in the docBase then the WAR
+     * overlays are searched
+     *
+     * See http://blog.bazoud.com/post/2009-05-12-multiples-docbases-avec-tomcat.html
+     */
+    private static class MultipleDirContext extends FileDirContext
+    {
+        private final ArrayList<FileDirContextAdapter> virtualContexts = new ArrayList<FileDirContextAdapter>();
+
+        public MultipleDirContext()
+        {
+           super();
+        }
+
+        public MultipleDirContext(Hashtable env)
+        {
+           super(env);
+        }
+
+        public void addVirtualDocBase(final String virtualDocBase)
+        {
+           FileDirContextAdapter x = new FileDirContextAdapter();
+           x.setDocBase(virtualDocBase);
+           virtualContexts.add(x);
+        }
+
+        @Override
+        public void allocate()
+        {
+            super.allocate();
+
+            for (final FileDirContextAdapter x : virtualContexts)
+            {
+                x.allocate();
+            }
+        }
+
+        @Override
+        public void release()
+        {
+            super.release();
+            for (final FileDirContextAdapter x : virtualContexts)
+            {
+                x.release();
+            }
+        }
+
+        @Override
+        protected File file(String name)
+        {
+            File ret = super.file(name);
+
+            if (ret == null)
+            {
+                for (final FileDirContextAdapter x : virtualContexts)
+                {
+                    ret = x.file(name);
+                    if (ret != null)
+                    {
+                        break;
+                    }
+                }
+            }
+
+            return ret;
+        }
+    }
+
+    /**
+     * Used to make {@link FileDirContext#file(java.lang.String)} accessible from this context
+     */
+    private static class FileDirContextAdapter extends FileDirContext
+    {
+        FileDirContextAdapter()
+        {
+            super();
+        }
+
+        FileDirContextAdapter(Hashtable env)
+        {
+            super(env);
+        }
+
+        @Override
+        protected File file(String name)
+        {
+            return super.file(name);
+        }
+    }
 }