/*
* JBoss, Home of Professional Open Source
* Copyright 2011, Red Hat, Inc. and/or its affiliates, and individual
* contributors by the @authors tag. See the copyright.txt in the
* distribution for a full listing of individual contributors.
*
* 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.jboss.seam.persistence.util;
import java.lang.annotation.Annotation;
import java.lang.reflect.Member;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.HashSet;
import java.util.Set;
import javax.enterprise.context.spi.CreationalContext;
import javax.enterprise.inject.Instance;
import javax.enterprise.inject.spi.Annotated;
import javax.enterprise.inject.spi.Bean;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.InjectionPoint;
import org.jboss.seam.solder.literal.DefaultLiteral;
/**
* Utillity class that can get an Instance<T> from the bean manager
*
* @author stuart
*
*/
public class InstanceResolver
{
private InstanceResolver()
{
}
public static <T> Instance<T> getInstance(Class<T> type, BeanManager manager)
{
return getInstance(type, manager, DefaultLiteral.INSTANCE);
}
public static <T> Instance<T> getInstance(Class<T> type, BeanManager manager, Annotation... qualifiers)
{
Type instanceType = new InstanceParamatizedTypeImpl<T>(type);
Bean<?> bean = manager.resolve(manager.getBeans(instanceType, qualifiers));
CreationalContext ctx = manager.createCreationalContext(bean);
return (Instance<T>) manager.getInjectableReference(new InstanceInjectionPoint<T>(type, qualifiers), ctx);
}
private static class InstanceParamatizedTypeImpl<T> implements ParameterizedType
{
private final Class<T> type;
public InstanceParamatizedTypeImpl(Class<T> type)
{
this.type = type;
}
public Type[] getActualTypeArguments()
{
Type[] ret = new Type[1];
ret[0] = type;
return ret;
}
public Type getOwnerType()
{
return null;
}
public Type getRawType()
{
return Instance.class;
}
}
/**
* TODO: this is not portable, needs to be a proper implementation as this
* could cause a NPE due to some methods returning null
*/
private static class InstanceInjectionPoint<T> implements InjectionPoint
{
private final Class<T> type;
private final Set<Annotation> qualifiers;
public InstanceInjectionPoint(Class<T> type, Annotation... quals)
{
this.type = type;
qualifiers = new HashSet<Annotation>();
for (Annotation a : quals)
{
qualifiers.add(a);
}
}
public Annotated getAnnotated()
{
return null;
}
public Bean<?> getBean()
{
return null;
}
public Member getMember()
{
return null;
}
public Set<Annotation> getQualifiers()
{
return qualifiers;
}
public Type getType()
{
return new InstanceParamatizedTypeImpl<T>(type);
}
public boolean isDelegate()
{
return false;
}
public boolean isTransient()
{
return false;
}
}
}