org.springframework.yarn.support.compat.NMTokenCacheCompat Maven / Gradle / Ivy
/*
* Copyright 2013 the original author or authors.
*
* 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.springframework.yarn.support.compat;
import java.lang.reflect.Method;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.yarn.client.api.NMTokenCache;
import org.springframework.util.ReflectionUtils;
/**
* Compat class for {@link NMTokenCache}.
*
* @author Janne Valkealahti
* @author Thomas Risberg
*/
public class NMTokenCacheCompat {
private final static Log log = LogFactory.getLog(NMTokenCacheCompat.class);
private static NMTokenCache nmTokenCache;
/** NMTokenCache init lock */
private final static Object lock = new Object();
/**
* Gets the Hadoop {@code NMTokenCache}. Access token cache via singleton
* method if exists, otherwise assumes that class is hadoop vanilla
* implementation with static methods where we can just use default
* constructor and further access for those static method would
* got via instance itself.
*
* This is due to a fact that i.e. cloudera modified this class by
* removing static methods and made access to it via singleton pattern.
*
* @return the token cache
*/
public static NMTokenCache getNMTokenCache() {
if (nmTokenCache == null) {
synchronized (lock) {
if (nmTokenCache == null) {
Method singletonMethod = ReflectionUtils.findMethod(NMTokenCache.class, "getSingleton");
if (singletonMethod != null) {
if (log.isDebugEnabled()) {
log.debug("Creating NMTokenCache using NMTokenCache.getSingleton()");
}
nmTokenCache = (NMTokenCache) ReflectionUtils.invokeMethod(singletonMethod, null);
} else {
log.debug("Creating NMTokenCache using constructor, further access via instance static methods.");
nmTokenCache = new NMTokenCache();
}
}
}
}
return nmTokenCache;
}
public static boolean containsToken(NMTokenCache nmTokenCache, String nodeId) {
if (nmTokenCache != null) {
Method method = ReflectionUtils.findMethod(NMTokenCache.class, "containsNMToken", String.class);
if (method == null) {
method = ReflectionUtils.findMethod(NMTokenCache.class, "containsToken", String.class);
}
if (method != null) {
boolean results = (Boolean)ReflectionUtils.invokeMethod(method, nmTokenCache, nodeId);
log.debug("NMTokenCache method " + method.getName() + " returned " + results);
return results;
} else {
log.debug("Unable to determine the name for 'containsToken' method on NMTokenCache class");
}
}
return false;
}
}