Java tutorial
/* * Copyright 2012 NGDATA nv * * 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.lilyproject.repository.bulk.serial; import java.io.IOException; import java.util.Collections; import java.util.List; import java.util.concurrent.ArrayBlockingQueue; import java.util.concurrent.ThreadPoolExecutor; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicLong; import com.google.common.collect.Lists; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.lilyproject.repository.api.Record; import org.lilyproject.repository.bulk.BulkIngester; import org.lilyproject.repository.bulk.RecordWriter; import org.lilyproject.util.concurrent.WaitPolicy; import org.lilyproject.util.exception.ExceptionUtil; /** * Import writer for bulk imports where the import runs as a single (multi-threaded) process writing directly to Lily. */ public class ThreadedRecordWriter implements RecordWriter { private Log log = LogFactory.getLog(getClass()); private String lilyZk; private String repositoryName; private String tableName; private boolean bulkMode; private ThreadPoolExecutor executor; private AtomicLong recordsWritten = new AtomicLong(); private AtomicLong writeFailures = new AtomicLong(); private ThreadLocal<BulkIngester> threadLocalBulkIngesters; private List<BulkIngester> bulkIngesters; public ThreadedRecordWriter(String lilyZk, int numThreads, String repositoryName, String tableName, boolean bulkMode) { this.lilyZk = lilyZk; this.repositoryName = repositoryName; this.tableName = tableName; this.bulkMode = bulkMode; executor = new ThreadPoolExecutor(numThreads, numThreads, 10, TimeUnit.SECONDS, new ArrayBlockingQueue<Runnable>(5)); executor.setRejectedExecutionHandler(new WaitPolicy()); threadLocalBulkIngesters = new ThreadLocal<BulkIngester>(); bulkIngesters = Collections.synchronizedList(Lists.<BulkIngester>newArrayList()); } @Override public void write(final Record record) throws IOException, InterruptedException { executor.submit(new Runnable() { @Override public void run() { if (threadLocalBulkIngesters.get() == null) { BulkIngester bulkIngester = BulkIngester.newBulkIngester(lilyZk, 30000, repositoryName, tableName, bulkMode); bulkIngesters.add(bulkIngester); threadLocalBulkIngesters.set(bulkIngester); } BulkIngester bulkIngester = threadLocalBulkIngesters.get(); try { bulkIngester.write(record); recordsWritten.incrementAndGet(); } catch (Exception e) { ExceptionUtil.handleInterrupt(e); log.error("Error writing record " + record, e); writeFailures.incrementAndGet(); } } }); } @Override public void close() { this.executor.shutdown(); boolean successfulFinish; try { successfulFinish = executor.awaitTermination(10, TimeUnit.MINUTES); } catch (InterruptedException e) { throw new RuntimeException(e); } if (!successfulFinish) { throw new RuntimeException("JSON import executor did not end successfully."); } for (BulkIngester bulkIngester : bulkIngesters) { try { bulkIngester.close(); } catch (IOException e) { log.error("Error closing bulk ingester", e); } } } public long getNumWriteFailures() { return writeFailures.longValue(); } @Override public long getNumRecords() { return recordsWritten.longValue(); } }