/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.envers.internal.entities.mapper.relation.lazy.proxy;

import java.io.Serializable;
import java.util.Collection;
import java.util.Iterator;

import org.hibernate.envers.internal.entities.mapper.relation.lazy.initializor.Initializor;

/**
 * @author Adam Warski (adam at warski dot org)
 */
public abstract class CollectionProxy<U, T extends Collection<U>> implements Collection<U>, Serializable {
	private static final long serialVersionUID = 8698249863871832402L;

	private transient org.hibernate.envers.internal.entities.mapper.relation.lazy.initializor.Initializor<T> initializor;
	protected T delegate;

	protected CollectionProxy() {
	}

	public CollectionProxy(Initializor<T> initializor) {
		this.initializor = initializor;
	}

	protected void checkInit() {
		if ( delegate == null ) {
			delegate = initializor.initialize();
		}
	}

	@Override
	public int size() {
		checkInit();
		return delegate.size();
	}

	@Override
	public boolean isEmpty() {
		checkInit();
		return delegate.isEmpty();
	}

	@Override
	public boolean contains(Object o) {
		checkInit();
		return delegate.contains( o );
	}

	@Override
	public Iterator<U> iterator() {
		checkInit();
		return delegate.iterator();
	}

	@Override
	public Object[] toArray() {
		checkInit();
		return delegate.toArray();
	}

	@Override
	public <V> V[] toArray(V[] a) {
		checkInit();
		return delegate.toArray( a );
	}

	@Override
	public boolean add(U o) {
		checkInit();
		return delegate.add( o );
	}

	@Override
	public boolean remove(Object o) {
		checkInit();
		return delegate.remove( o );
	}

	@Override
	public boolean containsAll(Collection<?> c) {
		checkInit();
		return delegate.containsAll( c );
	}

	@Override
	public boolean addAll(Collection<? extends U> c) {
		checkInit();
		return delegate.addAll( c );
	}

	@Override
	public boolean removeAll(Collection<?> c) {
		checkInit();
		return delegate.removeAll( c );
	}

	@Override
	public boolean retainAll(Collection<?> c) {
		checkInit();
		return delegate.retainAll( c );
	}

	@Override
	public void clear() {
		checkInit();
		delegate.clear();
	}

	@Override
	public String toString() {
		checkInit();
		return delegate.toString();
	}

	@SuppressWarnings({"EqualsWhichDoesntCheckParameterClass"})
	@Override
	public boolean equals(Object obj) {
		checkInit();
		return delegate.equals( obj );
	}

	@Override
	public int hashCode() {
		checkInit();
		return delegate.hashCode();
	}
}