public void reduce( IntWritable key, Iterator<RecordStatsWritable> values, OutputCollector<IntWritable, RecordStatsWritable> output, Reporter reporter) throws IOException { long bytes = 0; long records = 0; int xor = 0; while (values.hasNext()) { RecordStatsWritable stats = values.next(); bytes += stats.getBytes(); records += stats.getRecords(); xor ^= stats.getChecksum(); } output.collect(key, new RecordStatsWritable(bytes, records, xor)); }
static void checkRecords(Configuration defaults, Path sortInput, Path sortOutput) throws IOException { FileSystem inputfs = sortInput.getFileSystem(defaults); FileSystem outputfs = sortOutput.getFileSystem(defaults); FileSystem defaultfs = FileSystem.get(defaults); JobConf jobConf = new JobConf(defaults, RecordStatsChecker.class); jobConf.setJobName("sortvalidate-recordstats-checker"); int noSortReduceTasks = outputfs.listStatus(sortOutput, sortPathsFilter).length; jobConf.setInt("sortvalidate.sort.reduce.tasks", noSortReduceTasks); int noSortInputpaths = inputfs.listStatus(sortInput).length; jobConf.setInputFormat(NonSplitableSequenceFileInputFormat.class); jobConf.setOutputFormat(SequenceFileOutputFormat.class); jobConf.setOutputKeyClass(IntWritable.class); jobConf.setOutputValueClass(RecordStatsChecker.RecordStatsWritable.class); jobConf.setMapperClass(Map.class); jobConf.setCombinerClass(Reduce.class); jobConf.setReducerClass(Reduce.class); jobConf.setNumMapTasks(noSortReduceTasks); jobConf.setNumReduceTasks(1); FileInputFormat.setInputPaths(jobConf, sortInput); FileInputFormat.addInputPath(jobConf, sortOutput); Path outputPath = new Path("/tmp/sortvalidate/recordstatschecker"); if (defaultfs.exists(outputPath)) { defaultfs.delete(outputPath, true); } FileOutputFormat.setOutputPath(jobConf, outputPath); // Uncomment to run locally in a single process // job_conf.set("mapred.job.tracker", "local"); Path[] inputPaths = FileInputFormat.getInputPaths(jobConf); System.out.println( "\nSortValidator.RecordStatsChecker: Validate sort " + "from " + inputPaths[0] + " (" + noSortInputpaths + " files), " + inputPaths[1] + " (" + noSortReduceTasks + " files) into " + FileOutputFormat.getOutputPath(jobConf) + " with 1 reducer."); Date startTime = new Date(); System.out.println("Job started: " + startTime); JobClient.runJob(jobConf); Date end_time = new Date(); System.out.println("Job ended: " + end_time); System.out.println( "The job took " + (end_time.getTime() - startTime.getTime()) / 1000 + " seconds."); // Check to ensure that the statistics of the // framework's sort-input and sort-output match SequenceFile.Reader stats = new SequenceFile.Reader(defaultfs, new Path(outputPath, "part-00000"), defaults); IntWritable k1 = new IntWritable(); IntWritable k2 = new IntWritable(); RecordStatsWritable v1 = new RecordStatsWritable(); RecordStatsWritable v2 = new RecordStatsWritable(); if (!stats.next(k1, v1)) { throw new IOException("Failed to read record #1 from reduce's output"); } if (!stats.next(k2, v2)) { throw new IOException("Failed to read record #2 from reduce's output"); } if ((v1.getBytes() != v2.getBytes()) || (v1.getRecords() != v2.getRecords()) || v1.getChecksum() != v2.getChecksum()) { throw new IOException( "(" + v1.getBytes() + ", " + v1.getRecords() + ", " + v1.getChecksum() + ") v/s (" + v2.getBytes() + ", " + v2.getRecords() + ", " + v2.getChecksum() + ")"); } }