001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.apache.hadoop.security;
020    
021    import java.io.IOException;
022    import java.util.List;
023    
024    import org.apache.commons.logging.Log;
025    import org.apache.commons.logging.LogFactory;
026    import org.apache.hadoop.util.NativeCodeLoader;
027    import org.apache.hadoop.util.PerformanceAdvisory;
028    
029    public class JniBasedUnixGroupsMappingWithFallback implements
030        GroupMappingServiceProvider {
031    
032      private static final Log LOG = LogFactory
033          .getLog(JniBasedUnixGroupsMappingWithFallback.class);
034      
035      private GroupMappingServiceProvider impl;
036    
037      public JniBasedUnixGroupsMappingWithFallback() {
038        if (NativeCodeLoader.isNativeCodeLoaded()) {
039          this.impl = new JniBasedUnixGroupsMapping();
040        } else {
041          PerformanceAdvisory.LOG.debug("Falling back to shell based");
042          this.impl = new ShellBasedUnixGroupsMapping();
043        }
044        if (LOG.isDebugEnabled()){
045          LOG.debug("Group mapping impl=" + impl.getClass().getName());
046        }
047      }
048    
049      @Override
050      public List<String> getGroups(String user) throws IOException {
051        return impl.getGroups(user);
052      }
053    
054      @Override
055      public void cacheGroupsRefresh() throws IOException {
056        impl.cacheGroupsRefresh();
057      }
058    
059      @Override
060      public void cacheGroupsAdd(List<String> groups) throws IOException {
061        impl.cacheGroupsAdd(groups);
062      }
063    
064    }