Java tutorial
/** * 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.raid; import java.io.InputStream; import java.io.OutputStream; import java.io.IOException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.FSDataInputStream; import org.apache.hadoop.fs.FSDataOutputStream; import org.apache.hadoop.fs.Path; import org.apache.hadoop.util.Progressable; import java.nio.ByteBuffer; public class PMOEncoder extends Encoder { native void pmoEncode(ByteBuffer message, ByteBuffer parity, int k, int m, int bufferSize, ByteBuffer r); int seq; static { System.loadLibrary("pmoencoder"); } public static final Log LOG = LogFactory.getLog("org.apache.hadoop.raid.PMOEncoder"); private final ByteBuffer reserve; private ByteBuffer dataBufs; private ByteBuffer parityBufs; public PMOEncoder(Configuration conf, int stripeSize, int paritySize) { super(conf, stripeSize, paritySize); LOG.info("bufsize: " + bufSize); dataBufs = ByteBuffer.allocateDirect(bufSize * stripeSize); parityBufs = ByteBuffer.allocateDirect(bufSize * paritySize); reserve = ByteBuffer.allocateDirect(1024); } protected void encodeStripe(InputStream[] blocks, long stripeStartOffset, long blockSize, OutputStream[] outs, Progressable reporter) throws IOException { int[] data = new int[stripeSize]; int[] code = new int[paritySize]; seq = 0; for (long encoded = 0; encoded < blockSize; encoded += bufSize) { // Read some data from each block = bufSize. LOG.info("anchor Encode_stripe " + seq + " Data_start_reading " + System.nanoTime()); for (int i = 0; i < blocks.length; i++) { RaidUtils.readTillEnd(blocks[i], readBufs[i], true); } LOG.info("anchor Encode_stripe " + seq + " Data_read " + System.nanoTime()); // Encode the data read. //for (int j = 0; j < bufSize; j++) { performEncode(readBufs, writeBufs); //} // Now that we have some data to write, send it to the temp files. for (int i = 0; i < paritySize; i++) { if (i == 0) { LOG.info("anchor Output_parity " + i + seq + " Start_output " + System.nanoTime()); } outs[i].write(writeBufs[i], 0, bufSize); if (i == 0) LOG.info("anchor Output_parity " + i + seq + " End_output " + System.nanoTime()); } LOG.info("anchor Encode_stripe " + seq + " Parity_written " + System.nanoTime()); if (reporter != null) { reporter.progress(); } seq++; } } void performEncode(byte[][] readBufs, byte[][] writeBufs) { /* for (int i = 0; i < 2; i++) { code[i] = 0; } for (int i = 0; i < stripeSize; i++) { data[i] = readBufs[i][idx] & 0x000000FF; } */ //pmCode.encode(data, code); /* for (int i = 0; i < 2; i++) { writeBufs[i][idx] = (byte)code[i]; } */ dataBufs.rewind(); parityBufs.rewind(); for (int i = 0; i < stripeSize; i++) { dataBufs.put(readBufs[i], 0, bufSize); } LOG.info("before doing pmo encode with bufSize" + bufSize + " and array size " + readBufs[0].length); LOG.info("anchor Encode_stripe " + seq + " Start_encoding " + System.nanoTime()); pmoEncode(dataBufs, parityBufs, stripeSize, paritySize, bufSize, reserve); LOG.info("anchor Encode_stripe " + seq + " Encoded " + System.nanoTime()); LOG.info("after doing pmo encode"); for (int i = 0; i < paritySize; i++) { parityBufs.get(writeBufs[i], 0, bufSize); } } @Override public Path getParityTempPath() { return new Path(RaidNode.pmTempPrefix(conf)); } }