org.apache.wicket.guice.GuiceComponentInjector.java Source code

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Here is the source code for org.apache.wicket.guice.GuiceComponentInjector.java

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/*
 * 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.
 */
package org.apache.wicket.guice;

import com.google.inject.Guice;
import com.google.inject.ImplementedBy;
import com.google.inject.Injector;
import com.google.inject.Module;
import com.google.inject.Stage;
import org.apache.wicket.Application;
import org.apache.wicket.Component;
import org.apache.wicket.IBehaviorInstantiationListener;
import org.apache.wicket.Session;
import org.apache.wicket.application.IComponentInstantiationListener;
import org.apache.wicket.behavior.Behavior;
import org.apache.wicket.injection.IFieldValueFactory;
import org.apache.wicket.model.Model;

/**
 * Injects field members of components and behaviors using Guice.
 * <p>
 * Add this to your application in its {@link Application#init()} method like so:
 * 
 * <pre>
 * getComponentInstantiationListeners().add(new GuiceComponentInjector(this));
 * </pre>
 * 
 * <p>
 * There are different constructors for this object depending on how you want to wire things. See
 * the javadoc for the constructors for more information.
 * </p>
 * <p>
 * Only Wicket {@link Component}s and {@link Behavior}s are automatically injected, other classes
 * such as {@link Session}, {@link Model}, and any other POJO can be injected by calling
 * <code>Injector.get().inject(this)</code> in their constructor.
 * </p>
 * 
 * @author Alastair Maw
 */
public class GuiceComponentInjector extends org.apache.wicket.injection.Injector
        implements IComponentInstantiationListener, IBehaviorInstantiationListener {
    private final IFieldValueFactory fieldValueFactory;

    /**
     * Creates a new Wicket GuiceComponentInjector instance.
     * <p>
     * Internally this will create a new Guice {@link Injector} instance, with no {@link Module}
     * instances. This is only useful if your beans have appropriate {@link ImplementedBy}
     * annotations on them so that they can be automatically picked up with no extra configuration
     * code.
     * 
     * @param app
     */
    public GuiceComponentInjector(final Application app) {
        this(app, new Module[0]);
    }

    /**
     * Creates a new Wicket GuiceComponentInjector instance, using the supplied Guice {@link Module}
     * instances to create a new Guice {@link Injector} instance internally.
     * 
     * @param app
     * @param modules
     */
    public GuiceComponentInjector(final Application app, final Module... modules) {
        this(app, Guice.createInjector(app.usesDeploymentConfig() ? Stage.PRODUCTION : Stage.DEVELOPMENT, modules),
                true);
    }

    /**
     * Constructor
     * 
     * @param app
     * @param injector
     */
    public GuiceComponentInjector(final Application app, final Injector injector) {
        this(app, injector, true);
    }

    /**
     * Creates a new Wicket GuiceComponentInjector instance, using the provided Guice
     * {@link Injector} instance.
     * 
     * @param app
     * @param injector
     * @param wrapInProxies
     *            whether or not wicket should wrap dependencies with specialized proxies that can
     *            be safely serialized. in most cases this should be set to true.
     */
    public GuiceComponentInjector(final Application app, final Injector injector, final boolean wrapInProxies) {
        app.setMetaData(GuiceInjectorHolder.INJECTOR_KEY, new GuiceInjectorHolder(injector));
        fieldValueFactory = new GuiceFieldValueFactory(wrapInProxies);
        app.getBehaviorInstantiationListeners().add(this);
        bind(app);
    }

    @Override
    public void inject(final Object object) {
        inject(object, fieldValueFactory);
    }

    @Override
    public void onInstantiation(final Component component) {
        inject(component);
    }

    @Override
    public void onInstantiation(Behavior behavior) {
        inject(behavior);
    }
}