PicoContainer example source code file (InstanceAdapter.java)

This example PicoContainer source code file (InstanceAdapter.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

abstractadapter, behavior, class, componentmonitor, instanceadapter, instanceadapter, lifecyclestrategy, lifecyclestrategy, nullpointerexception, nullpointerexception, object, object, picocompositionexception

The PicoContainer InstanceAdapter.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                                                          *
 *****************************************************************************/
package org.picocontainer.adapters;

import org.picocontainer.Behavior;
import org.picocontainer.PicoContainer;
import org.picocontainer.LifecycleStrategy;
import org.picocontainer.ComponentMonitor;
import org.picocontainer.PicoCompositionException;
import org.picocontainer.adapters.AbstractAdapter;

/**
 * <p>
 * Component adapter which wraps a component instance.
 * </p>
 * <p>
 * This component adapter supports both a {@link Behavior Behavior} and a
 * {@link org.picocontainer.LifecycleStrategy LifecycleStrategy} to control the lifecycle of the component.
 * The lifecycle manager methods simply delegate to the lifecycle strategy methods 
 * on the component instance.
 * </p>
 * 
 * @author Aslak Hellesøy
 * @author Paul Hammant
 * @author Mauro Talevi
 * @version $Revision: 3633 $
 */
public final class InstanceAdapter extends AbstractAdapter implements Behavior, LifecycleStrategy {
    private final Object componentInstance;
    private final LifecycleStrategy lifecycleStrategy;

    public InstanceAdapter(Object componentKey, Object componentInstance, LifecycleStrategy lifecycleStrategy, ComponentMonitor componentMonitor) throws PicoCompositionException {
        super(componentKey, getInstanceClass(componentInstance), componentMonitor);
        this.componentInstance = componentInstance;
        this.lifecycleStrategy = lifecycleStrategy;
    }

    private static Class getInstanceClass(Object componentInstance) {
        if (componentInstance == null) {
            throw new NullPointerException("componentInstance cannot be null");
        }
        return componentInstance.getClass();
    }

    public Object getComponentInstance(PicoContainer container) {
        return componentInstance;
    }
    
    public void verify(PicoContainer container) {
    }

    public void start(PicoContainer container) {
        start(componentInstance);
    }

    public void stop(PicoContainer container) {
        stop(componentInstance);
    }

    public void dispose(PicoContainer container) {
        dispose(componentInstance);
    }

    public boolean componentHasLifecycle() {
        return hasLifecycle(componentInstance.getClass());
    }

    // ~~~~~~~~ LifecycleStrategy ~~~~~~~~
    
    public void start(Object component) {
        lifecycleStrategy.start(componentInstance);
    }

    public void stop(Object component) {
        lifecycleStrategy.stop(componentInstance);
    }

    public void dispose(Object component) {
        lifecycleStrategy.dispose(componentInstance);
    }

    public boolean hasLifecycle(Class type) {
        return lifecycleStrategy.hasLifecycle(type);
    }

}