PicoContainer example source code file (AbstractComponentMonitor.java)

This example PicoContainer source code file (AbstractComponentMonitor.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - PicoContainer tags/keywords

abstractcomponentmonitor, componentadapter, componentadapter, componentmonitor, componentmonitorstrategy, componentmonitorstrategy, constructor, constructor, exception, io, method, nullpointerexception, object, object, reflection, serializable

The PicoContainer AbstractComponentMonitor.java source code

/*****************************************************************************
 * Copyright (C) PicoContainer Organization. All rights reserved.            *
 * ------------------------------------------------------------------------- *
 * The software in this package is published under the terms of the BSD      *
 * style license a copy of which has been included with this distribution in *
 * the LICENSE.txt file.                                                     *
 *                                                                           *
 * Original code by Mauro Talevi                                             *
 *****************************************************************************/

package org.picocontainer.monitors;

import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Member;

import org.picocontainer.ComponentMonitor;
import org.picocontainer.ComponentMonitorStrategy;
import org.picocontainer.ComponentAdapter;
import org.picocontainer.MutablePicoContainer;
import org.picocontainer.PicoContainer;
import org.picocontainer.monitors.NullComponentMonitor;

/**
 * <p>
 * A {@link ComponentMonitor monitor} which delegates to another monitor.
 * It provides a {@link NullComponentMonitor default ComponentMonitor},
 * but does not allow to use <code>null for the delegate.
 * </p>
 * <p>
 * It also supports a {@link org.picocontainer.ComponentMonitorStrategy monitor strategy}
 * that allows to change the delegate.
 * </p>
 * 
 * @author Mauro Talevi
 * @version $Revision: $
 */
public class AbstractComponentMonitor implements ComponentMonitor, ComponentMonitorStrategy, Serializable {

    private  ComponentMonitor delegate;
    
    /**
     * Creates a AbstractComponentMonitor with a given delegate
     * @param delegate the ComponentMonitor to which this monitor delegates
     */
    public AbstractComponentMonitor(ComponentMonitor delegate) {
        checkMonitor(delegate);
        this.delegate = delegate;
    }

    /**
     * Creates a AbstractComponentMonitor with an instance of
     * {@link NullComponentMonitor}.
     */
    public AbstractComponentMonitor() {
        this(NullComponentMonitor.getInstance());
    }
    
    public Constructor instantiating(PicoContainer container, ComponentAdapter componentAdapter,
                                     Constructor constructor
    ) {
        return delegate.instantiating(container, componentAdapter, constructor);
    }

    public void instantiated(PicoContainer container, ComponentAdapter componentAdapter,
                             Constructor constructor,
                             Object instantiated,
                             Object[] injected,
                             long duration) {
        delegate.instantiated(container, componentAdapter, constructor, instantiated, injected, duration);
    }

    public void instantiationFailed(PicoContainer container,
                                    ComponentAdapter componentAdapter,
                                    Constructor constructor,
                                    Exception e) {
        delegate.instantiationFailed(container, componentAdapter, constructor, e);
    }

    public void invoking(PicoContainer container,
                         ComponentAdapter componentAdapter,
                         Member member,
                         Object instance) {
        delegate.invoking(container, componentAdapter, member, instance);
    }

    public void invoked(PicoContainer container,
                        ComponentAdapter componentAdapter,
                        Method method,
                        Object instance,
                        long duration) {
        delegate.invoked(container, componentAdapter, method, instance, duration);
    }

    public void invocationFailed(Member member, Object instance, Exception e) {
        delegate.invocationFailed(member, instance, e);
    }

    public void lifecycleInvocationFailed(MutablePicoContainer container,
                                          ComponentAdapter componentAdapter, Method method,
                                          Object instance,
                                          RuntimeException cause) {
        delegate.lifecycleInvocationFailed(container, componentAdapter, method,instance, cause);
    }

    public Object noComponentFound(MutablePicoContainer container, Object componentKey) {
        return delegate.noComponentFound(container, componentKey);
    }

    /**
     * If the delegate supports a {@link ComponentMonitorStrategy monitor strategy},
     * this is used to changed the monitor while keeping the same delegate.
     * Else the delegate is replaced by the new monitor.
     * {@inheritDoc}
     */
    public void changeMonitor(ComponentMonitor monitor) {
        checkMonitor(monitor);
        if ( delegate instanceof ComponentMonitorStrategy ){
            ((ComponentMonitorStrategy)delegate).changeMonitor(monitor);
        } else {
            delegate = monitor;
        }
    }

    public ComponentMonitor currentMonitor() {
        if ( delegate instanceof ComponentMonitorStrategy ){
            return ((ComponentMonitorStrategy)delegate).currentMonitor();
        } else {
            return delegate;
        }
    }
    
    private void checkMonitor(ComponentMonitor monitor) {
        if ( monitor == null ){
            throw new NullPointerException("monitor");
        }
    }

}