/**
 * 
 */
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;

/**
 * Class encapsulating 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);
        }
    }

}