src/main/java/org/apache/maven/demo/extension/EventSpyDemo.java

package org.apache.maven.demo.extension;

/*
 * 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.
 */

import java.util.HashMap;
import java.util.Map;

import org.apache.maven.eventspy.AbstractEventSpy;
import org.apache.maven.eventspy.EventSpy;
import org.apache.maven.execution.ExecutionEvent;
import org.apache.maven.plugin.MojoExecution;
import org.apache.maven.project.MavenProject;
import org.codehaus.plexus.DefaultPlexusContainer;
import org.codehaus.plexus.classworlds.ClassWorld;
import org.codehaus.plexus.classworlds.realm.ClassRealm;
import org.codehaus.plexus.component.annotations.Component;
import org.eclipse.aether.RepositoryEvent;

/**
 * Event Spy demo (since Maven 3.0.2, with <a href="https://issues.apache.org/jira/browse/MNG-4936">MNG-4936</a>).
 * <p>Notice: event spies are not activated from POM build extensions.
 */
//@Named( "demo" )
//@Singleton
@Component( role = EventSpy.class, hint = "demo" ) // using Plexus Component annotations for Maven 3.0.x
public class EventSpyDemo
    extends AbstractEventSpy
{
    private Map<String, Integer> events = new HashMap<String, Integer>();

    private DefaultPlexusContainer container;

    public void init( Context context )
        throws Exception
    {
        System.err.println( "EventSpyDemo init:" );
        for ( Map.Entry<String, Object> entry : context.getData().entrySet() )
        {
            System.err.println( "             init context: - " + entry.getKey() + " = " + entry.getValue() );
        }
        container = (DefaultPlexusContainer) context.getData().get( "plexus" );
        dump( container.getClassWorld() );
    }

    public void onEvent( Object event )
        throws Exception
    {
        if ( event instanceof ExecutionEvent )
        {
            ExecutionEvent exec = (ExecutionEvent) event;
            MavenProject project = exec.getProject();
            MojoExecution mojoExec = exec.getMojoExecution();
            Exception ex = exec.getException();
            System.err.println( "EventSpyDemo onEvent: ExecutionEvent " + exec.getType()
                + ( project == null ? "" : ( " " + project.getId() ) )
                + ( mojoExec == null ? "" : ( " " + mojoExec ) )
                + ( ex == null ? "" : ( " " + ex ) ) );
        }
        else if ( event instanceof RepositoryEvent )
        {
            RepositoryEvent repo = (RepositoryEvent) event;
            if ( repo.getType() == RepositoryEvent.EventType.ARTIFACT_RESOLVING
                || repo.getType() == RepositoryEvent.EventType.ARTIFACT_RESOLVED )
            {
              // don't display these evens: too many artifacts resolved along execution
            }
            else
            {
              System.err.println( "EventSpyDemo onEvent: RepositoryEvent " + ( (RepositoryEvent) event ).getType() );
            }
        }
        else
        {
            System.err.println( "EventSpyDemo onEvent: " + event.getClass().getName() );
        }
        Integer count = events.get( event.getClass().getName() );
        if ( count == null )
        {
            count = 1;
        }
        else
        {
            count++;
        }
        events.put( event.getClass().getName(), count );
    }

    public void close()
        throws Exception
    {
        System.err.println( "EventSpyDemo close:" );
        for ( Map.Entry<String, Integer> entry : events.entrySet() )
        {
            System.err.println( "             - " + entry.getValue() + " " + entry.getKey() );
        }
        //dump( container.getClassWorld() );
    }

    private void dump( ClassWorld cw )
    {
        for ( ClassRealm cr : cw.getRealms() )
        {
            System.err.println( "EventSpyDemo - ClassRealm " + cr.getId() );
            cr.display( System.err );
        }
    }
}