/*
 * Copyright 2005-2010 the original author or authors.
 * 
 * Licensed 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.wamblee.cdi;

import javax.enterprise.context.spi.CreationalContext;
import javax.enterprise.inject.spi.AnnotatedType;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.InjectionTarget;

import org.wamblee.inject.Injector;

/**
 * Class encapsulating bean injection into a specific non-contextual object of a
 * given class.
 * 
 * @author Erik Brakkee
 */
public class CdiInjector implements Injector {
    private Class clazz;
    private InjectionTarget target;
    private CreationalContext ctx;

    /**
     * Constructs the injector.
     * 
     * @param aMgr
     *            Bean manager.
     * @param aClass
     *            Class to analyse for injection.
     */
    public CdiInjector(BeanManager aMgr, Class<?> aClass) {
        clazz = aClass;
        AnnotatedType<?> type = aMgr.createAnnotatedType(aClass);
        target = aMgr.createInjectionTarget(type);
        ctx = aMgr.createCreationalContext(null);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.wamblee.cdi.Injector#inject(java.lang.Object)
     */
    public void inject(Object aComponent) {
        if (aComponent != null) {
            if (!clazz.isInstance(aComponent)) {
                throw new RuntimeException("Object '" + aComponent +
                    "' is of type " + aComponent.getClass().getName() +
                    " but expected " + clazz.getName());
            }
            target.inject(aComponent, ctx);
        }
    }

}