首页 > 代码库 > 【Hadoop】Hadoop MR 自定义排序
【Hadoop】Hadoop MR 自定义排序
1、概念
2、代码示例
FlowSort
package com.ares.hadoop.mr.flowsort;import java.io.IOException;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.conf.Configured;import org.apache.hadoop.fs.Path;import org.apache.hadoop.io.LongWritable;import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Job;import org.apache.hadoop.mapreduce.Mapper;import org.apache.hadoop.mapreduce.Reducer;import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;import org.apache.hadoop.util.StringUtils;import org.apache.hadoop.util.Tool;import org.apache.hadoop.util.ToolRunner;import org.apache.log4j.Logger;import com.ares.hadoop.mr.exception.LineException;public class FlowSort extends Configured implements Tool { private static final Logger LOGGER = Logger.getLogger(FlowSort.class); enum Counter { LINESKIP } public static class FlowSortMapper extends Mapper<LongWritable, Text, FlowBean, NullWritable> { private String line; private int length; private final static char separator = ‘\t‘; private String phoneNum; private long upFlow; private long downFlow; private long sumFlow; private FlowBean flowBean = new FlowBean(); private NullWritable nullWritable = NullWritable.get(); @Override protected void map( LongWritable key, Text value, Mapper<LongWritable, Text, FlowBean, NullWritable>.Context context) throws IOException, InterruptedException { // TODO Auto-generated method stub //super.map(key, value, context); String errMsg; try { line = value.toString(); String[] fields = StringUtils.split(line, separator); length = fields.length; if (length != 4) { throw new LineException(key.get() + ", " + line + " LENGTH INVALID, IGNORE..."); } phoneNum = fields[0]; upFlow = Long.parseLong(fields[1]); downFlow = Long.parseLong(fields[2]); sumFlow = Long.parseLong(fields[3]); flowBean.setPhoneNum(phoneNum); flowBean.setUpFlow(upFlow); flowBean.setDownFlow(downFlow); flowBean.setSumFlow(sumFlow); context.write(flowBean, nullWritable); } catch (LineException e) { // TODO: handle exception LOGGER.error(e); System.out.println(e); context.getCounter(Counter.LINESKIP).increment(1); return; } catch (NumberFormatException e) { // TODO: handle exception errMsg = key.get() + ", " + line + " FLOW DATA INVALID, IGNORE..."; LOGGER.error(errMsg); System.out.println(errMsg); context.getCounter(Counter.LINESKIP).increment(1); return; } catch (Exception e) { // TODO: handle exception LOGGER.error(e); System.out.println(e); context.getCounter(Counter.LINESKIP).increment(1); return; } } } public static class FlowSortReducer extends Reducer<FlowBean, NullWritable, FlowBean, NullWritable> { @Override protected void reduce( FlowBean key, Iterable<NullWritable> values, Reducer<FlowBean, NullWritable, FlowBean, NullWritable>.Context context) throws IOException, InterruptedException { // TODO Auto-generated method stub //super.reduce(arg0, arg1, arg2); context.write(key, NullWritable.get()); } } @Override public int run(String[] args) throws Exception { // TODO Auto-generated method stub String errMsg = "FlowSort: TEST STARTED..."; LOGGER.debug(errMsg); System.out.println(errMsg); Configuration conf = new Configuration(); //FOR Eclipse JVM Debug //conf.set("mapreduce.job.jar", "flowsum.jar"); Job job = Job.getInstance(conf); // JOB NAME job.setJobName("FlowSort"); // JOB MAPPER & REDUCER job.setJarByClass(FlowSort.class); job.setMapperClass(FlowSortMapper.class); job.setReducerClass(FlowSortReducer.class); // MAP & REDUCE job.setOutputKeyClass(FlowBean.class); job.setOutputValueClass(NullWritable.class); // MAP job.setMapOutputKeyClass(FlowBean.class); job.setMapOutputValueClass(NullWritable.class); // JOB INPUT & OUTPUT PATH //FileInputFormat.addInputPath(job, new Path(args[0])); FileInputFormat.setInputPaths(job, args[1]); FileOutputFormat.setOutputPath(job, new Path(args[2])); // VERBOSE OUTPUT if (job.waitForCompletion(true)) { errMsg = "FlowSort: TEST SUCCESSFULLY..."; LOGGER.debug(errMsg); System.out.println(errMsg); return 0; } else { errMsg = "FlowSort: TEST FAILED..."; LOGGER.debug(errMsg); System.out.println(errMsg); return 1; } } public static void main(String[] args) throws Exception { if (args.length != 3) { String errMsg = "FlowSort: ARGUMENTS ERROR"; LOGGER.error(errMsg); System.out.println(errMsg); System.exit(-1); } int result = ToolRunner.run(new Configuration(), new FlowSort(), args); System.exit(result); }}
FlowBean
package com.ares.hadoop.mr.flowsort;import java.io.DataInput;import java.io.DataOutput;import java.io.IOException;import org.apache.hadoop.io.WritableComparable;public class FlowBean implements WritableComparable<FlowBean>{ private String phoneNum; private long upFlow; private long downFlow; private long sumFlow; public FlowBean() { // TODO Auto-generated constructor stub } // public FlowBean(String phoneNum, long upFlow, long downFlow, long sumFlow) {// super();// this.phoneNum = phoneNum;// this.upFlow = upFlow;// this.downFlow = downFlow;// this.sumFlow = sumFlow;// } public String getPhoneNum() { return phoneNum; } public void setPhoneNum(String phoneNum) { this.phoneNum = phoneNum; } public long getUpFlow() { return upFlow; } public void setUpFlow(long upFlow) { this.upFlow = upFlow; } public long getDownFlow() { return downFlow; } public void setDownFlow(long downFlow) { this.downFlow = downFlow; } public long getSumFlow() { return sumFlow; } public void setSumFlow(long sumFlow) { this.sumFlow = sumFlow; } @Override public void readFields(DataInput in) throws IOException { // TODO Auto-generated method stub phoneNum = in.readUTF(); upFlow = in.readLong(); downFlow = in.readLong(); sumFlow = in.readLong(); } @Override public void write(DataOutput out) throws IOException { // TODO Auto-generated method stub out.writeUTF(phoneNum); out.writeLong(upFlow); out.writeLong(downFlow); out.writeLong(sumFlow); } @Override public String toString() { return "" + phoneNum + "\t" + upFlow + "\t" + downFlow + "\t" + sumFlow; } @Override public int compareTo(FlowBean o) { // TODO Auto-generated method stub return sumFlow>o.getSumFlow()?-1:1; } }
LineException
package com.ares.hadoop.mr.exception;public class LineException extends RuntimeException { private static final long serialVersionUID = 2536144005398058435L; public LineException() { super(); // TODO Auto-generated constructor stub } public LineException(String message, Throwable cause) { super(message, cause); // TODO Auto-generated constructor stub } public LineException(String message) { super(message); // TODO Auto-generated constructor stub } public LineException(Throwable cause) { super(cause); // TODO Auto-generated constructor stub }}
【Hadoop】Hadoop MR 自定义排序
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