Java tutorial
package org.apache.hawq.pxf.service; /* * 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. */ import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.security.UserGroupInformation; import java.io.IOException; /** * Thin wrapper around {@link UserGroupInformation} create and destroy methods. We mock this class * in tests to be able to detect when a UGI is created/destroyed, and to isolate our tests from * creating/destroying real UGI instances. */ class UGIProvider { /** * Wrapper for {@link UserGroupInformation} creation * * @param effectiveUser the name of the user that we want to impersonate * @return a {@link UserGroupInformation} for impersonation. * @throws IOException */ UserGroupInformation createProxyUGI(String effectiveUser) throws IOException { return UserGroupInformation.createProxyUser(effectiveUser, UserGroupInformation.getLoginUser()); } /** * Wrapper for {@link FileSystem}.closeAllForUGI method. * @param ugi the {@link UserGroupInformation} whose filesystem resources we want to free. * @throws IOException */ void destroy(UserGroupInformation ugi) throws IOException { FileSystem.closeAllForUGI(ugi); } }