/*
* 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 parquet.hadoop.util;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.Counter;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.JobID;
import org.apache.hadoop.mapreduce.MapContext;
import org.apache.hadoop.mapreduce.OutputCommitter;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.StatusReporter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.TaskAttemptID;
import org.apache.hadoop.mapreduce.TaskInputOutputContext;
/*
* This is based on ContextFactory.java from hadoop-2.0.x sources.
*/
/**
* Utility methods to allow applications to deal with inconsistencies between
* MapReduce Context Objects API between hadoop-0.20 and later versions.
*/
public class ContextUtil {
private static final boolean useV21;
private static final Constructor<?> JOB_CONTEXT_CONSTRUCTOR;
private static final Constructor<?> TASK_CONTEXT_CONSTRUCTOR;
private static final Constructor<?> MAP_CONTEXT_CONSTRUCTOR;
private static final Constructor<?> MAP_CONTEXT_IMPL_CONSTRUCTOR;
private static final Constructor<?> GENERIC_COUNTER_CONSTRUCTOR;
private static final Field READER_FIELD;
private static final Field WRITER_FIELD;
private static final Field OUTER_MAP_FIELD;
private static final Field WRAPPED_CONTEXT_FIELD;
private static final Method GET_CONFIGURATION_METHOD;
private static final Method GET_COUNTER_METHOD;
private static final Method INCREMENT_COUNTER_METHOD;
static {
boolean v21 = true;
final String PACKAGE = "org.apache.hadoop.mapreduce";
try {
Class.forName(PACKAGE + ".task.JobContextImpl");
} catch (ClassNotFoundException cnfe) {
v21 = false;
}
useV21 = v21;
Class<?> jobContextCls;
Class<?> taskContextCls;
Class<?> taskIOContextCls;
Class<?> mapCls;
Class<?> mapContextCls;
Class<?> innerMapContextCls;
Class<?> genericCounterCls;
try {
if (v21) {
jobContextCls =
Class.forName(PACKAGE + ".task.JobContextImpl");
taskContextCls =
Class.forName(PACKAGE + ".task.TaskAttemptContextImpl");
taskIOContextCls =
Class.forName(PACKAGE + ".task.TaskInputOutputContextImpl");
mapContextCls = Class.forName(PACKAGE + ".task.MapContextImpl");
mapCls = Class.forName(PACKAGE + ".lib.map.WrappedMapper");
innerMapContextCls =
Class.forName(PACKAGE + ".lib.map.WrappedMapper$Context");
genericCounterCls = Class.forName(PACKAGE + ".counters.GenericCounter");
} else {
jobContextCls =
Class.forName(PACKAGE + ".JobContext");
taskContextCls =
Class.forName(PACKAGE + ".TaskAttemptContext");
taskIOContextCls =
Class.forName(PACKAGE + ".TaskInputOutputContext");
mapContextCls = Class.forName(PACKAGE + ".MapContext");
mapCls = Class.forName(PACKAGE + ".Mapper");
innerMapContextCls =
Class.forName(PACKAGE + ".Mapper$Context");
genericCounterCls =
Class.forName("org.apache.hadoop.mapred.Counters$Counter");
}
} catch (ClassNotFoundException e) {
throw new IllegalArgumentException("Can't find class", e);
}
try {
JOB_CONTEXT_CONSTRUCTOR =
jobContextCls.getConstructor(Configuration.class, JobID.class);
JOB_CONTEXT_CONSTRUCTOR.setAccessible(true);
TASK_CONTEXT_CONSTRUCTOR =
taskContextCls.getConstructor(Configuration.class,
TaskAttemptID.class);
TASK_CONTEXT_CONSTRUCTOR.setAccessible(true);
GENERIC_COUNTER_CONSTRUCTOR =
genericCounterCls.getDeclaredConstructor(String.class,
String.class,
Long.TYPE);
GENERIC_COUNTER_CONSTRUCTOR.setAccessible(true);
if (useV21) {
MAP_CONTEXT_CONSTRUCTOR =
innerMapContextCls.getConstructor(mapCls,
MapContext.class);
MAP_CONTEXT_IMPL_CONSTRUCTOR =
mapContextCls.getDeclaredConstructor(Configuration.class,
TaskAttemptID.class,
RecordReader.class,
RecordWriter.class,
OutputCommitter.class,
StatusReporter.class,
InputSplit.class);
MAP_CONTEXT_IMPL_CONSTRUCTOR.setAccessible(true);
WRAPPED_CONTEXT_FIELD =
innerMapContextCls.getDeclaredField("mapContext");
WRAPPED_CONTEXT_FIELD.setAccessible(true);
Method get_counter_method;
try {
get_counter_method = Class.forName(PACKAGE + ".TaskAttemptContext").getMethod("getCounter", String.class,
String.class);
} catch (Exception e) {
get_counter_method = Class.forName(PACKAGE + ".TaskInputOutputContext").getMethod("getCounter",
String.class, String.class);
}
GET_COUNTER_METHOD = get_counter_method;
} else {
MAP_CONTEXT_CONSTRUCTOR =
innerMapContextCls.getConstructor(mapCls,
Configuration.class,
TaskAttemptID.class,
RecordReader.class,
RecordWriter.class,
OutputCommitter.class,
StatusReporter.class,
InputSplit.class);
MAP_CONTEXT_IMPL_CONSTRUCTOR = null;
WRAPPED_CONTEXT_FIELD = null;
GET_COUNTER_METHOD = taskIOContextCls.getMethod("getCounter", String.class, String.class);
}
MAP_CONTEXT_CONSTRUCTOR.setAccessible(true);
READER_FIELD = mapContextCls.getDeclaredField("reader");
READER_FIELD.setAccessible(true);
WRITER_FIELD = taskIOContextCls.getDeclaredField("output");
WRITER_FIELD.setAccessible(true);
OUTER_MAP_FIELD = innerMapContextCls.getDeclaredField("this$0");
OUTER_MAP_FIELD.setAccessible(true);
GET_CONFIGURATION_METHOD = Class.forName(PACKAGE + ".JobContext")
.getMethod("getConfiguration");
INCREMENT_COUNTER_METHOD = Class.forName(PACKAGE + ".Counter")
.getMethod("increment", Long.TYPE);
} catch (SecurityException e) {
throw new IllegalArgumentException("Can't run constructor ", e);
} catch (NoSuchMethodException e) {
throw new IllegalArgumentException("Can't find constructor ", e);
} catch (NoSuchFieldException e) {
throw new IllegalArgumentException("Can't find field ", e);
} catch (ClassNotFoundException e) {
throw new IllegalArgumentException("Can't find class", e);
}
}
/**
* Creates JobContext from a JobConf and jobId using the correct constructor
* for based on Hadoop version. <code>jobId</code> could be null.
*/
public static JobContext newJobContext(Configuration conf, JobID jobId) {
try {
return (JobContext)
JOB_CONTEXT_CONSTRUCTOR.newInstance(conf, jobId);
} catch (InstantiationException e) {
throw new IllegalArgumentException("Can't instantiate JobContext", e);
} catch (IllegalAccessException e) {
throw new IllegalArgumentException("Can't instantiate JobContext", e);
} catch (InvocationTargetException e) {
throw new IllegalArgumentException("Can't instantiate JobContext", e);
}
}
/**
* Creates TaskAttempContext from a JobConf and jobId using the correct
* constructor for based on Hadoop version.
*/
public static TaskAttemptContext newTaskAttemptContext(
Configuration conf, TaskAttemptID taskAttemptId) {
try {
return (TaskAttemptContext)
TASK_CONTEXT_CONSTRUCTOR.newInstance(conf, taskAttemptId);
} catch (InstantiationException e) {
throw new IllegalArgumentException("Can't instantiate TaskAttemptContext", e);
} catch (IllegalAccessException e) {
throw new IllegalArgumentException("Can't instantiate TaskAttemptContext", e);
} catch (InvocationTargetException e) {
throw new IllegalArgumentException("Can't instantiate TaskAttemptContext", e);
}
}
/**
* @return with Hadoop 2 : <code>new GenericCounter(args)</code>,<br>
* with Hadoop 1 : <code>new Counter(args)</code>
*/
public static Counter newGenericCounter(String name, String displayName, long value) {
try {
return (Counter)
GENERIC_COUNTER_CONSTRUCTOR.newInstance(name, displayName, value);
} catch (InstantiationException e) {
throw new IllegalArgumentException("Can't instantiate Counter", e);
} catch (IllegalAccessException e) {
throw new IllegalArgumentException("Can't instantiate Counter", e);
} catch (InvocationTargetException e) {
throw new IllegalArgumentException("Can't instantiate Counter", e);
}
}
/**
* Invoke getConfiguration() method on JobContext. Works with both
* Hadoop 1 and 2.
*/
public static Configuration getConfiguration(JobContext context) {
try {
return (Configuration) GET_CONFIGURATION_METHOD.invoke(context);
} catch (IllegalAccessException e) {
throw new IllegalArgumentException("Can't invoke method", e);
} catch (InvocationTargetException e) {
throw new IllegalArgumentException("Can't invoke method", e);
}
}
public static Counter getCounter(TaskInputOutputContext context,
String groupName, String counterName) {
return (Counter) invoke(GET_COUNTER_METHOD, context, groupName, counterName);
}
/**
* Invokes a method and rethrows any exception as runtime exceptions.
*/
private static Object invoke(Method method, Object obj, Object... args) {
try {
return method.invoke(obj, args);
} catch (IllegalAccessException e) {
throw new IllegalArgumentException("Can't invoke method " + method.getName(), e);
} catch (InvocationTargetException e) {
throw new IllegalArgumentException("Can't invoke method " + method.getName(), e);
}
}
public static void incrementCounter(Counter counter, long increment) {
invoke(INCREMENT_COUNTER_METHOD, counter, increment);
}
}