/*
 * 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.jena.permissions.model.impl;

import org.apache.jena.permissions.SecuredItem;
import org.apache.jena.rdf.model.*;
import org.apache.jena.shared.AuthenticationRequiredException;
import org.apache.jena.shared.ReadDeniedException;

public class SecuredSelector implements Selector {
	private final SecuredItem securedItem;
	private final Selector selector;

	public SecuredSelector(final SecuredItem securedItem) {
		this(securedItem, new SimpleSelector());
	}

	public SecuredSelector(final SecuredItem securedItem,
			final Selector selector) {
		this.securedItem = securedItem;
		this.selector = selector;
	}

	@Override
	public RDFNode getObject() {
		return selector.getObject();
	}

	@Override
	public Property getPredicate() {
		return selector.getPredicate();
	}

	@Override
	public Resource getSubject() {
		return selector.getSubject();
	}

	@Override
	public boolean isSimple() {
		return selector.isSimple();
	}

	/**
	 * This method is designed to be over ridden by subclasses to define
	 * application specific constraints on the statements selected.
	 * 
	 * @param s
	 *            the statement to be tested
	 * @return true if the statement satisfies the constraint
	 * @throws ReadDeniedException
	 * @throws AuthenticationRequiredException
	 */
	@Override
	public boolean test(final Statement s) throws ReadDeniedException,
			AuthenticationRequiredException {
		if (securedItem.canRead(s)) {
			return selector.test(s);
		}
		return false;
	}

}