org.apache.hadoop.security.NullGroupsMapping Maven / Gradle / Ivy
/*
* Copyright 2015 Apache Software Foundation.
*
* 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.apache.hadoop.security;
import java.util.Collections;
import java.util.List;
/**
* This class provides groups mapping for {@link UserGroupInformation} when the
* user group information will not be used.
*/
public class NullGroupsMapping implements GroupMappingServiceProvider {
/**
* Nothing is returned, so nothing is cached.
* @param groups ignored
*/
@Override
public void cacheGroupsAdd(List groups) {
}
/**
* Returns an empty list.
* @param user ignored
* @return an empty list
*/
@Override
public List getGroups(String user) {
return Collections.emptyList();
}
/**
* Nothing is returned, so nothing is cached.
*/
@Override
public void cacheGroupsRefresh() {
}
}