/**
* 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.yarn.client.api;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.hadoop.classification.InterfaceAudience.Private;
import org.apache.hadoop.classification.InterfaceAudience.Public;
import org.apache.hadoop.classification.InterfaceStability.Evolving;
import org.apache.hadoop.yarn.api.records.Token;
import com.google.common.annotations.VisibleForTesting;
/**
* It manages NMTokens required for communicating with Node manager. Its a
* static token cache.
*/
@Public
@Evolving
public class NMTokenCache {
private static ConcurrentHashMap<String, Token> nmTokens;
static {
nmTokens = new ConcurrentHashMap<String, Token>();
}
/**
* Returns NMToken, null if absent
* @param nodeAddr
* @return {@link Token} NMToken required for communicating with node
* manager
*/
@Public
@Evolving
public static Token getNMToken(String nodeAddr) {
return nmTokens.get(nodeAddr);
}
/**
* Sets the NMToken for node address
* @param nodeAddr node address (host:port)
* @param token NMToken
*/
@Public
@Evolving
public static void setNMToken(String nodeAddr, Token token) {
nmTokens.put(nodeAddr, token);
}
/**
* Returns true if NMToken is present in cache.
*/
@Private
@VisibleForTesting
public static boolean containsNMToken(String nodeAddr) {
return nmTokens.containsKey(nodeAddr);
}
/**
* Returns the number of NMTokens present in cache.
*/
@Private
@VisibleForTesting
public static int numberOfNMTokensInCache() {
return nmTokens.size();
}
/**
* Removes NMToken for specified node manager
* @param nodeAddr node address (host:port)
*/
@Private
@VisibleForTesting
public static void removeNMToken(String nodeAddr) {
nmTokens.remove(nodeAddr);
}
/**
* It will remove all the nm tokens from its cache
*/
@Private
@VisibleForTesting
public static void clearCache() {
nmTokens.clear();
}
}