[HUDSON-5360] add a new classloader ("a la" child first for plugin)

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@35076 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/PluginFirstClassLoader.java

@@ -0,0 +1,105 @@
+/*
+ * The MIT License
+ * 
+ * Copyright (c) 2004-2009, Sun Microsystems, Inc., Olivier Lamy
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Enumeration;
+import java.util.List;
+
+import org.apache.tools.ant.AntClassLoader;
+
+/**
+ * classLoader which use first /WEB-INF/lib/*.jar and /WEB-INF/classes before core classLoader
+ * <b>you must use the pluginFirstClassLoader true in the maven-hpi-plugin</b>
+ * @author olamy
+ * @since 1.371
+ */
+public class PluginFirstClassLoader
+    extends AntClassLoader
+    implements Closeable
+{
+    
+    private List<URL> urls = new ArrayList<URL>();
+
+    public void addPathFiles( Collection<File> paths )
+        throws IOException
+    {
+        for ( File f : paths )
+        {
+            urls.add( f.toURI().toURL() );
+            addPathFile( f );
+        }
+    }
+
+    /**
+     * @return List of jar used by the plugin /WEB-INF/lib/*.jar and classes directory /WEB-INF/classes
+     */
+    public List<URL> getURLs() 
+    {
+        return urls;
+    }
+    
+    public void close()
+        throws IOException
+    {
+        cleanup();
+    }
+
+    @Override
+    protected Enumeration findResources( String arg0, boolean arg1 )
+        throws IOException
+    {
+        Enumeration enu = super.findResources( arg0, arg1 );
+        return enu;
+    }
+
+    @Override
+    protected Enumeration findResources( String name )
+        throws IOException
+    {
+        Enumeration enu = super.findResources( name );
+        return enu;
+    }
+
+    @Override
+    public URL getResource( String arg0 )
+    {
+        URL url = super.getResource( arg0 );
+        return url;
+    }
+
+    @Override
+    public InputStream getResourceAsStream( String name )
+    {
+        InputStream is = super.getResourceAsStream( name );
+        return is;
+    }   
+    
+}