com.marklogic.contentpump.BaseMapper Maven / Gradle / Ivy
/*
* Copyright (c) 2019 MarkLogic Corporation
*
* 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 com.marklogic.contentpump;
import java.io.IOException;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.mapreduce.InputSplit;
/**
* Content Pump base mapper with the capability to run in thread-safe mode.
*
* @author jchen
*
* @param
* @param
* @param
* @param
*/
public class BaseMapper extends
org.apache.hadoop.mapreduce.Mapper {
public static final Log LOG = LogFactory.getLog(BaseMapper.class);
public void runThreadSafe(Context outerCtx, Context subCtx)
throws IOException, InterruptedException {
setup(subCtx);
KEYIN key = null;
VALUEIN value = null;
try {
while (!ContentPump.shutdown) {
synchronized (outerCtx) {
if (!subCtx.nextKeyValue()) {
break;
}
key = subCtx.getCurrentKey();
value = subCtx.getCurrentValue();
}
map(key, value, subCtx);
}
} finally {
if (ContentPump.shutdown && LOG.isDebugEnabled()) {
LOG.debug("Aborting task...");
}
cleanup(subCtx);
}
}
public int getRequiredThreads() {
return 1;
}
public List> submitTasks(ExecutorService threadPool,
InputSplit inputSplit) {
return Collections.emptyList();
}
@Override
public void run(Context context) throws IOException, InterruptedException {
setup(context);
try {
while (!ContentPump.shutdown && context.nextKeyValue()) {
map(context.getCurrentKey(), context.getCurrentValue(), context);
}
} finally {
if (ContentPump.shutdown && LOG.isDebugEnabled()) {
LOG.debug("Aborting task...");
}
cleanup(context);
}
}
}