Java tutorial
/* CountKmer.java 2012 CloudBrush, developed by Chien-Chih Chen (rocky@iis.sinica.edu.tw), released under Apache License 2.0 (http://www.apache.org/licenses/LICENSE-2.0) at: https://github.com/ice91/CloudBrush*/ package Brush; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.Set; import java.util.List; import java.util.Map; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.conf.Configured; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.mapred.FileInputFormat; import org.apache.hadoop.mapred.FileOutputFormat; import org.apache.hadoop.mapred.JobClient; import org.apache.hadoop.mapred.JobConf; import org.apache.hadoop.mapred.MapReduceBase; import org.apache.hadoop.mapred.Mapper; import org.apache.hadoop.mapred.OutputCollector; import org.apache.hadoop.mapred.Reducer; import org.apache.hadoop.mapred.Reporter; import org.apache.hadoop.mapred.RunningJob; import org.apache.hadoop.mapred.TextInputFormat; import org.apache.hadoop.mapred.TextOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; import org.apache.log4j.Logger; public class CountKmer extends Configured implements Tool { private static final Logger sLogger = Logger.getLogger(MatchPrefix.class); public static class CountKmerMapper extends MapReduceBase implements Mapper<LongWritable, Text, Text, Text> { public static int K = 0; public static int TRIM5 = 0; public static int TRIM3 = 0; public void configure(JobConf job) { K = Integer.parseInt(job.get("K")); } public void map(LongWritable lineid, Text nodetxt, OutputCollector<Text, Text> output, Reporter reporter) throws IOException { Node node = new Node(); node.fromNodeMsg(nodetxt.toString()); if (!node.hasCustom("n")) { reporter.incrCounter("Brush", "nodes", 1); //slide the K-mer windows for each read in both strands int end = node.len() - K; for (int i = 0; i < end; i++) { String window_tmp = node.str().substring(i, i + K); String window_r_tmp = Node.rc(node.str().substring(node.len() - K - i, node.len() - i)); //String window_r_tmp = Node.rc(window_tmp); String window = Node.str2dna(window_tmp); String window_r = Node.str2dna(window_r_tmp); //output.collect(new Text(window), new IntWritable((int)node.cov())); //output.collect(new Text(window_r), new IntWritable((int)node.cov())); output.collect(new Text(window), new Text((int) node.cov() + "|" + node.getNodeId())); output.collect(new Text(window_r), new Text((int) node.cov() + "|" + node.getNodeId())); reporter.incrCounter("Brush", "Allkmer", (int) node.cov()); } } } } public static class CountKmerReducer extends MapReduceBase implements Reducer<Text, Text, Text, Text> { private static int K = 0; //private static int OVALSIZE = 0; private static int All_Kmer = 0; public void configure(JobConf job) { K = Integer.parseInt(job.get("K")); } public void reduce(Text prefix, Iterator<Text> iter, OutputCollector<Text, Text> output, Reporter reporter) throws IOException { int sum = 0; int read_count = 0; List<String> ReadID_list = new ArrayList<String>(); while (iter.hasNext()) { String msg = iter.next().toString(); String[] vals = msg.split("\\|"); sum += Integer.parseInt(vals[0]); if (ReadID_list.contains(vals[1])) { // do nothing } else { read_count = read_count + 1; ReadID_list.add(vals[1]); } } output.collect(new Text(prefix.toString()), new Text(sum + "")); if (sum >= 2) { reporter.incrCounter("Brush", "Diffkmer", 1); } } } public RunningJob run(String inputPath, String outputPath) throws Exception { sLogger.info("Tool name: CountKmer"); sLogger.info(" - input: " + inputPath); sLogger.info(" - output: " + outputPath); JobConf conf = new JobConf(CountKmer.class); conf.setJobName("CountKmer " + inputPath + " " + BrushConfig.K); BrushConfig.initializeConfiguration(conf); FileInputFormat.addInputPath(conf, new Path(inputPath)); FileOutputFormat.setOutputPath(conf, new Path(outputPath)); conf.setInputFormat(TextInputFormat.class); conf.setOutputFormat(TextOutputFormat.class); conf.setMapOutputKeyClass(Text.class); //conf.setMapOutputValueClass(IntWritable.class); conf.setMapOutputValueClass(Text.class); conf.setOutputKeyClass(Text.class); conf.setOutputValueClass(Text.class); //conf.setBoolean("mapred.output.compress", true); conf.setMapperClass(CountKmerMapper.class); conf.setReducerClass(CountKmerReducer.class); //delete the output directory if it exists already FileSystem.get(conf).delete(new Path(outputPath), true); return JobClient.runJob(conf); } public int run(String[] args) throws Exception { String inputPath = ""; String outputPath = ""; BrushConfig.K = 21; long starttime = System.currentTimeMillis(); run(inputPath, outputPath); long endtime = System.currentTimeMillis(); float diff = (float) (((float) (endtime - starttime)) / 1000.0); System.out.println("Runtime: " + diff + " s"); return 0; } public static void main(String[] args) throws Exception { int res = ToolRunner.run(new Configuration(), new CountKmer(), args); System.exit(res); } }