Factory.java

/*
 * 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.graph.impl;

import org.apache.jena.graph.Graph ;
import org.apache.jena.permissions.SecurityEvaluator;
import org.apache.jena.permissions.graph.SecuredGraph;
import org.apache.jena.permissions.graph.SecuredPrefixMapping;
import org.apache.jena.permissions.impl.ItemHolder;
import org.apache.jena.permissions.impl.SecuredItemInvoker;
import org.apache.jena.shared.PrefixMapping ;

public class Factory
{

	/**
	 * Create an instance of SecuredPrefixMapping
	 * 
	 * @param graph
	 *            The SecuredGraph that contains the prefixmapping.
	 * @param prefixMapping
	 *            The prefixmapping returned from the base graph.
	 * @return The SecuredPrefixMapping.
	 */
	static SecuredPrefixMapping getInstance( final SecuredGraphImpl graph,
			final PrefixMapping prefixMapping )
	{

		final ItemHolder<PrefixMapping, SecuredPrefixMapping> holder = new ItemHolder<PrefixMapping, SecuredPrefixMapping>(
				prefixMapping);
		final SecuredPrefixMappingImpl checker = new SecuredPrefixMappingImpl(
				graph, holder);
		// if we are going to create a duplicate proxy just return this one.
		if (prefixMapping instanceof SecuredPrefixMapping)
		{
			if (checker.isEquivalent((SecuredPrefixMapping) prefixMapping))
			{
				return (SecuredPrefixMapping) prefixMapping;
			}
		}

		return holder.setSecuredItem(new SecuredItemInvoker(prefixMapping
				.getClass(), checker));
	}

	/**
	 * Create an instance of the SecuredGraph
	 * 
	 * @param securityEvaluator
	 *            The security evaluator to use
	 * @param graphIRI
	 *            The IRI for the graph.
	 * @param graph
	 *            The graph that we are wrapping.
	 * @return the secured graph
	 */
	public static SecuredGraph getInstance(
			final SecurityEvaluator securityEvaluator, final String graphIRI,
			final Graph graph )
	{

		final ItemHolder<Graph, SecuredGraphImpl> holder = new ItemHolder<Graph, SecuredGraphImpl>(
				graph);
		final SecuredGraphImpl checker = new SecuredGraphImpl(
				securityEvaluator, graphIRI, holder) {
		};

		// If we going to create a duplicate proxy return this one.
		if (graph instanceof SecuredGraphImpl)
		{
			if (checker.isEquivalent((SecuredGraphImpl) graph))
			{
				return (SecuredGraph) graph;
			}
		}
		return holder.setSecuredItem(new SecuredItemInvoker(graph.getClass(),
				checker));
	}

}