MockIdMapper.java

/* $HeadURL$
 * $Id$
 *
 * Copyright (c) 2009-2010 DuraSpace
 * http://duraspace.org
 *
 * In collaboration with Topaz Inc.
 * http://www.topazproject.org
 *
 * 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.akubraproject.map;

import java.net.URI;

/**
 * Simple {@link IdMapper} implementation for testing. Internal ids are
 * the same as external ids, optionally prepended with a given
 * <code>uriPrefix</code>.
 *
 * @author Chris Wilper
 */
public class MockIdMapper implements IdMapper {
  private final String uriPrefix;
  private final boolean prefixMappable;

  public MockIdMapper() {
    this(null, true);
  }

  /**
   * Creates an instance.
   *
   * @param uriPrefix the uriPrefix to use for internal ids, "" or <code>null</code>
   *        if no prefix should be used.
   * @param prefixMappable for the purpose of testing, whether prefixes should
   *        be considered mappable or not. If <code>false</code>, requests
   *        to {@link #getInternalPrefix} will always return <code>null</code>.
   */
  public MockIdMapper(String uriPrefix, boolean prefixMappable) {
    if (uriPrefix == null)
      this.uriPrefix = "";
    else
      this.uriPrefix = uriPrefix;
    this.prefixMappable = prefixMappable;
  }

  public URI getExternalId(URI internalId) throws NullPointerException {
    if (internalId == null)
      throw new NullPointerException();
    if (!internalId.toString().startsWith(uriPrefix))
      throw new IllegalArgumentException();
    return URI.create(internalId.toString().substring(uriPrefix.length()));
  }

  public URI getInternalId(URI externalId) throws NullPointerException {
    if (externalId == null)
      throw new NullPointerException();
    return URI.create(uriPrefix + externalId);
  }

  public String getInternalPrefix(String externalPrefix) throws NullPointerException {
    if (externalPrefix == null)
      throw new NullPointerException();
    if (prefixMappable)
      return uriPrefix + externalPrefix;
    else
      return null;
  }

}