Java tutorial
/** * 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.hadoop.security; import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTH_TO_LOCAL; import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTH_TO_LOCAL_MECHANISM; import java.io.IOException; import org.apache.hadoop.classification.InterfaceAudience; import org.apache.hadoop.classification.InterfaceStability; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.security.authentication.util.KerberosName; import org.apache.hadoop.security.authentication.util.KerberosUtil; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * This class implements parsing and handling of Kerberos principal names. In * particular, it splits them apart and translates them down into local * operating system names. */ @SuppressWarnings("all") @InterfaceAudience.LimitedPrivate({ "HDFS", "MapReduce" }) @InterfaceStability.Evolving public class HadoopKerberosName extends KerberosName { private static final Logger LOG = LoggerFactory.getLogger(HadoopKerberosName.class); /** * Create a name from the full Kerberos principal name. * @param name */ public HadoopKerberosName(String name) { super(name); } /** * Set the static configuration to get and evaluate the rules. * <p> * IMPORTANT: This method does a NOP if the rules have been set already. * If there is a need to reset the rules, the {@link KerberosName#setRules(String)} * method should be invoked directly. * * @param conf the new configuration * @throws IOException */ public static void setConfiguration(Configuration conf) throws IOException { final String defaultRule; switch (SecurityUtil.getAuthenticationMethod(conf)) { case KERBEROS: case KERBEROS_SSL: try { KerberosUtil.getDefaultRealm(); } catch (Exception ke) { throw new IllegalArgumentException("Can't get Kerberos realm", ke); } defaultRule = "DEFAULT"; break; default: // just extract the simple user name defaultRule = "RULE:[1:$1] RULE:[2:$1]"; break; } String ruleString = conf.get(HADOOP_SECURITY_AUTH_TO_LOCAL, defaultRule); setRules(ruleString); String ruleMechanism = conf.get(HADOOP_SECURITY_AUTH_TO_LOCAL_MECHANISM, DEFAULT_MECHANISM); setRuleMechanism(ruleMechanism); } public static void main(String[] args) throws Exception { setConfiguration(new Configuration()); for (String arg : args) { HadoopKerberosName name = new HadoopKerberosName(arg); System.out.println("Name: " + name + " to " + name.getShortName()); } } }