| /** |
| * 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.util; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.PrintWriter; |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.ThreadInfo; |
| import java.lang.management.ThreadMXBean; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.Method; |
| import java.util.Map; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configurable; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.io.DataInputBuffer; |
| import org.apache.hadoop.io.DataOutputBuffer; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.io.serializer.Deserializer; |
| import org.apache.hadoop.io.serializer.SerializationFactory; |
| import org.apache.hadoop.io.serializer.Serializer; |
| |
| /** |
| * General reflection utils |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Evolving |
| public class ReflectionUtils { |
| |
| private static final Class<?>[] EMPTY_ARRAY = new Class[]{}; |
| volatile private static SerializationFactory serialFactory = null; |
| |
| /** |
| * Cache of constructors for each class. Pins the classes so they |
| * can't be garbage collected until ReflectionUtils can be collected. |
| */ |
| private static final Map<Class<?>, Constructor<?>> CONSTRUCTOR_CACHE = |
| new ConcurrentHashMap<Class<?>, Constructor<?>>(); |
| |
| /** |
| * Check and set 'configuration' if necessary. |
| * |
| * @param theObject object for which to set configuration |
| * @param conf Configuration |
| */ |
| public static void setConf(Object theObject, Configuration conf) { |
| if (conf != null) { |
| if (theObject instanceof Configurable) { |
| ((Configurable) theObject).setConf(conf); |
| } |
| setJobConf(theObject, conf); |
| } |
| } |
| |
| /** |
| * This code is to support backward compatibility and break the compile |
| * time dependency of core on mapred. |
| * This should be made deprecated along with the mapred package HADOOP-1230. |
| * Should be removed when mapred package is removed. |
| */ |
| private static void setJobConf(Object theObject, Configuration conf) { |
| //If JobConf and JobConfigurable are in classpath, AND |
| //theObject is of type JobConfigurable AND |
| //conf is of type JobConf then |
| //invoke configure on theObject |
| try { |
| Class<?> jobConfClass = |
| conf.getClassByNameOrNull("org.apache.hadoop.mapred.JobConf"); |
| if (jobConfClass == null) { |
| return; |
| } |
| |
| Class<?> jobConfigurableClass = |
| conf.getClassByNameOrNull("org.apache.hadoop.mapred.JobConfigurable"); |
| if (jobConfigurableClass == null) { |
| return; |
| } |
| if (jobConfClass.isAssignableFrom(conf.getClass()) && |
| jobConfigurableClass.isAssignableFrom(theObject.getClass())) { |
| Method configureMethod = |
| jobConfigurableClass.getMethod("configure", jobConfClass); |
| configureMethod.invoke(theObject, conf); |
| } |
| } catch (Exception e) { |
| throw new RuntimeException("Error in configuring object", e); |
| } |
| } |
| |
| /** Create an object for the given class and initialize it from conf |
| * |
| * @param theClass class of which an object is created |
| * @param conf Configuration |
| * @return a new object |
| */ |
| @SuppressWarnings("unchecked") |
| public static <T> T newInstance(Class<T> theClass, Configuration conf) { |
| T result; |
| try { |
| Constructor<T> meth = (Constructor<T>) CONSTRUCTOR_CACHE.get(theClass); |
| if (meth == null) { |
| meth = theClass.getDeclaredConstructor(EMPTY_ARRAY); |
| meth.setAccessible(true); |
| CONSTRUCTOR_CACHE.put(theClass, meth); |
| } |
| result = meth.newInstance(); |
| } catch (Exception e) { |
| throw new RuntimeException(e); |
| } |
| setConf(result, conf); |
| return result; |
| } |
| |
| static private ThreadMXBean threadBean = |
| ManagementFactory.getThreadMXBean(); |
| |
| public static void setContentionTracing(boolean val) { |
| threadBean.setThreadContentionMonitoringEnabled(val); |
| } |
| |
| private static String getTaskName(long id, String name) { |
| if (name == null) { |
| return Long.toString(id); |
| } |
| return id + " (" + name + ")"; |
| } |
| |
| /** |
| * Print all of the thread's information and stack traces. |
| * |
| * @param stream the stream to |
| * @param title a string title for the stack trace |
| */ |
| public static void printThreadInfo(PrintWriter stream, |
| String title) { |
| final int STACK_DEPTH = 20; |
| boolean contention = threadBean.isThreadContentionMonitoringEnabled(); |
| long[] threadIds = threadBean.getAllThreadIds(); |
| stream.println("Process Thread Dump: " + title); |
| stream.println(threadIds.length + " active threads"); |
| for (long tid: threadIds) { |
| ThreadInfo info = threadBean.getThreadInfo(tid, STACK_DEPTH); |
| if (info == null) { |
| stream.println(" Inactive"); |
| continue; |
| } |
| stream.println("Thread " + |
| getTaskName(info.getThreadId(), |
| info.getThreadName()) + ":"); |
| Thread.State state = info.getThreadState(); |
| stream.println(" State: " + state); |
| stream.println(" Blocked count: " + info.getBlockedCount()); |
| stream.println(" Waited count: " + info.getWaitedCount()); |
| if (contention) { |
| stream.println(" Blocked time: " + info.getBlockedTime()); |
| stream.println(" Waited time: " + info.getWaitedTime()); |
| } |
| if (state == Thread.State.WAITING) { |
| stream.println(" Waiting on " + info.getLockName()); |
| } else if (state == Thread.State.BLOCKED) { |
| stream.println(" Blocked on " + info.getLockName()); |
| stream.println(" Blocked by " + |
| getTaskName(info.getLockOwnerId(), |
| info.getLockOwnerName())); |
| } |
| stream.println(" Stack:"); |
| for (StackTraceElement frame: info.getStackTrace()) { |
| stream.println(" " + frame.toString()); |
| } |
| } |
| stream.flush(); |
| } |
| |
| private static long previousLogTime = 0; |
| |
| /** |
| * Log the current thread stacks at INFO level. |
| * @param log the logger that logs the stack trace |
| * @param title a descriptive title for the call stacks |
| * @param minInterval the minimum time from the last |
| */ |
| public static void logThreadInfo(Log log, |
| String title, |
| long minInterval) { |
| boolean dumpStack = false; |
| if (log.isInfoEnabled()) { |
| synchronized (ReflectionUtils.class) { |
| long now = System.currentTimeMillis(); |
| if (now - previousLogTime >= minInterval * 1000) { |
| previousLogTime = now; |
| dumpStack = true; |
| } |
| } |
| if (dumpStack) { |
| ByteArrayOutputStream buffer = new ByteArrayOutputStream(); |
| printThreadInfo(new PrintWriter(buffer), title); |
| log.info(buffer.toString()); |
| } |
| } |
| } |
| |
| /** |
| * Return the correctly-typed {@link Class} of the given object. |
| * |
| * @param o object whose correctly-typed <code>Class</code> is to be obtained |
| * @return the correctly typed <code>Class</code> of the given object. |
| */ |
| @SuppressWarnings("unchecked") |
| public static <T> Class<T> getClass(T o) { |
| return (Class<T>)o.getClass(); |
| } |
| |
| // methods to support testing |
| static void clearCache() { |
| CONSTRUCTOR_CACHE.clear(); |
| } |
| |
| static int getCacheSize() { |
| return CONSTRUCTOR_CACHE.size(); |
| } |
| /** |
| * A pair of input/output buffers that we use to clone writables. |
| */ |
| private static class CopyInCopyOutBuffer { |
| DataOutputBuffer outBuffer = new DataOutputBuffer(); |
| DataInputBuffer inBuffer = new DataInputBuffer(); |
| /** |
| * Move the data from the output buffer to the input buffer. |
| */ |
| void moveData() { |
| inBuffer.reset(outBuffer.getData(), outBuffer.getLength()); |
| } |
| } |
| |
| /** |
| * Allocate a buffer for each thread that tries to clone objects. |
| */ |
| private static ThreadLocal<CopyInCopyOutBuffer> cloneBuffers |
| = new ThreadLocal<CopyInCopyOutBuffer>() { |
| protected synchronized CopyInCopyOutBuffer initialValue() { |
| return new CopyInCopyOutBuffer(); |
| } |
| }; |
| |
| private static SerializationFactory getFactory(Configuration conf) { |
| if (serialFactory == null) { |
| serialFactory = new SerializationFactory(conf); |
| } |
| return serialFactory; |
| } |
| |
| /** |
| * Make a copy of the writable object using serialization to a buffer |
| * @param dst the object to copy from |
| * @param src the object to copy into, which is destroyed |
| * @throws IOException |
| */ |
| @SuppressWarnings("unchecked") |
| public static <T> T copy(Configuration conf, |
| T src, T dst) throws IOException { |
| CopyInCopyOutBuffer buffer = cloneBuffers.get(); |
| buffer.outBuffer.reset(); |
| SerializationFactory factory = getFactory(conf); |
| Class<T> cls = (Class<T>) src.getClass(); |
| Serializer<T> serializer = factory.getSerializer(cls); |
| serializer.open(buffer.outBuffer); |
| serializer.serialize(src); |
| buffer.moveData(); |
| Deserializer<T> deserializer = factory.getDeserializer(cls); |
| deserializer.open(buffer.inBuffer); |
| dst = deserializer.deserialize(dst); |
| return dst; |
| } |
| |
| @Deprecated |
| public static void cloneWritableInto(Writable dst, |
| Writable src) throws IOException { |
| CopyInCopyOutBuffer buffer = cloneBuffers.get(); |
| buffer.outBuffer.reset(); |
| src.write(buffer.outBuffer); |
| buffer.moveData(); |
| dst.readFields(buffer.inBuffer); |
| } |
| } |