Java tutorial
/** 4MC Copyright (c) 2014, Carlo Medas BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. You can contact 4MC author at : - 4MC source repository : https://github.com/carlomedas/4mc LZ4 - Copyright (C) 2011-2014, Yann Collet - BSD 2-Clause License. You can contact LZ4 lib author at : - LZ4 source repository : http://code.google.com/p/lz4/ **/ package format; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FSDataInputStream; import org.apache.hadoop.fs.FileStatus; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.fs.PathFilter; import org.apache.hadoop.mapreduce.InputSplit; import org.apache.hadoop.mapreduce.JobContext; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.input.FileSplit; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.io.IOException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; /** * An {@link org.apache.hadoop.mapreduce.InputFormat} for 4mc compressed files. * This is the base class, mainly managing input splits, leveraging 4mc block index. * * Subclasses must only make sure to provide an implementation of createRecordReader. * See {@link com.hadoop.mapreduce.FourMcTextInputFormat} as example reading text files. * * <b>Note:</b> unlikely default hadoop, but exactly like the EB version * this recursively examines directories for matching files. */ public abstract class OverlapInputFormat<K, V> extends FileInputFormat<K, V> { private static final Log LOG = LogFactory.getLog(OverlapInputFormat.class.getName()); private final PathFilter hiddenPathFilter = new PathFilter() { // avoid hidden files and directories. public boolean accept(Path path) { String name = path.getName(); return !name.startsWith(".") && !name.startsWith("_"); } }; private final PathFilter visible4mcFilter = new PathFilter() { public boolean accept(Path path) { String name = path.getName(); return !name.startsWith(".") && !name.startsWith("_"); //&& FourMcInputFormatUtil.is4mcFile(name); } }; @Override protected List<FileStatus> listStatus(JobContext job) throws IOException { List<FileStatus> files = super.listStatus(job); List<FileStatus> results = new ArrayList<FileStatus>(); // Configuration conf = HadoopUtils.getConfiguration(job); Configuration conf = job.getConfiguration(); boolean recursive = conf.getBoolean("mapred.input.dir.recursive", false); Iterator<FileStatus> it = files.iterator(); while (it.hasNext()) { FileStatus fileStatus = it.next(); FileSystem fs = fileStatus.getPath().getFileSystem(conf); addInputPath(results, fs, fileStatus, recursive); } LOG.debug("Total pcap input paths to process: " + results.size()); return results; } protected void addInputPath(List<FileStatus> results, FileSystem fs, FileStatus pathStat, boolean recursive) throws IOException { Path path = pathStat.getPath(); if (pathStat.isDir()) { if (recursive) { for (FileStatus stat : fs.listStatus(path, hiddenPathFilter)) { addInputPath(results, fs, stat, recursive); } } } else if (visible4mcFilter.accept(path)) { results.add(pathStat); } } @Override protected boolean isSplitable(JobContext context, Path filename) { return true; } /****** @Override public List<InputSplit> getSplits(JobContext job) throws IOException { Configuration conf = HadoopUtils.getConfiguration(job); List<InputSplit> defaultSplits = super.getSplits(job); List<InputSplit> result = new ArrayList<InputSplit>(); Path prevFile = null; FourMcBlockIndex prevIndex = null; for (InputSplit genericSplit : defaultSplits) { // Load the index. FileSplit fileSplit = (FileSplit) genericSplit; Path file = fileSplit.getPath(); FileSystem fs = file.getFileSystem(conf); FourMcBlockIndex index; if (file.equals(prevFile)) { index = prevIndex; } else { index = FourMcBlockIndex.readIndex(fs, file); prevFile = file; prevIndex = index; } if (index == null) { throw new IOException("BlockIndex unreadable for " + file); } if (index.isEmpty()) { // leave the default split for empty block index result.add(fileSplit); continue; } long start = fileSplit.getStart(); long end = start + fileSplit.getLength(); long fourMcStart = index.alignSliceStartToIndex(start, end); long fourMcEnd = index.alignSliceEndToIndex(end, fs.getFileStatus(file).getLen()); if (fourMcStart != FourMcBlockIndex.NOT_FOUND && fourMcEnd != FourMcBlockIndex.NOT_FOUND) { result.add(new FileSplit(file, fourMcStart, fourMcEnd - fourMcStart, fileSplit.getLocations())); LOG.debug("Added 4mc split for " + file + "[start=" + fourMcStart + ", length=" + (fourMcEnd - fourMcStart) + "]"); } } return result; } ******/ @Override public List<InputSplit> getSplits(JobContext context) { List<InputSplit> splits = new ArrayList<InputSplit>(); FileSystem fs = null; Path file = OverlapInputFormat.getInputPaths(context)[0]; Configuration conf = context.getConfiguration(); long blocksize = Long.parseLong(conf.get("dfs.blocksize")); // long overlap = Long.parseLong(conf.get("pcap.defaultsize")); long overlap = 16; FSDataInputStream in = null; try { fs = FileSystem.get(context.getConfiguration()); in = fs.open(file); long pos = 0; while (in.available() > 0) { FileSplit split = new FileSplit(file, pos, blocksize + overlap, new String[] {}); splits.add(split); pos += blocksize; in.skip(blocksize + overlap); } } catch (IOException e) { LOG.error(e.getLocalizedMessage()); } finally { if (in != null) { try { in.close(); } catch (Exception e) { } } ; if (fs != null) { try { fs.close(); } catch (Exception e) { } } ; } return splits; } }