MapReduce自定义排序编程

排序和分组

• 在map和reduce阶段进行排序时，比较的是k2。v2是不参与排序比较的。如果要想让v2也进行排序，需要把k2和v2组装成新的类，作为k2，才能参与比较。
• 分组时也是按照k2进行比较的。

案例说明

数据：

zhangsan@163.com600002014-02-20
lisi@163.com200002014-02-20
lisi@163.com01002014-02-20
zhangsan@163.com300002014-02-20
wangwu@126.com900002014-02-20
wangwu@126.com02002014-02-20

 

 

 

6

 

 

 

 

 

1

zhangsan@163.com600002014-02-20

2

lisi@163.com200002014-02-20

3

lisi@163.com01002014-02-20

4

zhangsan@163.com300002014-02-20

5

wangwu@126.com900002014-02-20

6

wangwu@126.com02002014-02-20

 

 

数据分析

• SumStep

  用户	收入	支出	结余
  lisi@163.com	2000	100	1900
  wangwu@126.com	9000	200	8800
  zhangsan@163.com	9000	0	9000

• SortStep

  用户	收入	支出	结余
  zhangsan@163.com	9000	0	9000
  wangwu@126.com	9000	200	8800
  lisi@163.com	2000	100	1900

InfoBean类

  import java.io.DataInput;
  import java.io.DataOutput;
  import java.io.IOException;

  import org.apache.hadoop.io.WritableComparable;

  public class InfoBean implements WritableComparable<InfoBean>{

    private String accout;
    private double incom;
    private double zhichu;
    private double jieyu;

    @Override
    public void write(DataOutput out) throws IOException {
      // TODO Auto-generated method stub
      out.writeUTF(accout);
      out.writeDouble(incom);
      out.writeDouble(zhichu);
      out.writeDouble(jieyu);
    }

    @Override
    public void readFields(DataInput in) throws IOException {
      // TODO Auto-generated method stub
      this.accout=in.readUTF();
      this.incom=in.readDouble();
      this.zhichu=in.readDouble();
      this.jieyu=in.readDouble();
    }

    @Override
    public int compareTo(InfoBean infoBean) {
      if(this.incom == infoBean.getIncom()){
        return this.zhichu > infoBean.getZhichu() ? 1 : -1;
      }else{
        return this.incom > infoBean.getIncom() ? -1 : 1;
      }
    }

    public String getAccout() {
      return accout;
    }

    public void setAccout(String accout) {
      this.accout = accout;
    }

    public double getIncom() {
      return incom;
    }

    public void setIncom(double incom) {
      this.incom = incom;
    }

    public double getZhichu() {
      return zhichu;
    }

    public void setZhichu(double zhichu) {
      this.zhichu = zhichu;
    }

    public double getJieyu() {
      return jieyu;
    }

    public void setJieyu(double jieyu) {
      this.jieyu = jieyu;
    }

    @Override
    public String toString() {
      return incom +"	" + zhichu +"	" + jieyu;
    }

    public void set(String accout,double incom,double zhichu){
      this.accout=accout;
      this.incom=incom;
      this.zhichu=zhichu;
      this.jieyu=incom - zhichu;
    }
  }

 

 

 

84

 

 

 

 

 

1

  import java.io.DataInput;

2

  import java.io.DataOutput;

3

  import java.io.IOException;

4

5

  import org.apache.hadoop.io.WritableComparable;

6

7

  public class InfoBean implements WritableComparable<InfoBean>{

8

9

    private String accout;

10

    private double incom;

11

    private double zhichu;

12

    private double jieyu;

13

14

    @Override

15

    public void write(DataOutput out) throws IOException {

16

      // TODO Auto-generated method stub

17

      out.writeUTF(accout);

18

      out.writeDouble(incom);

19

      out.writeDouble(zhichu);

20

      out.writeDouble(jieyu);

21

    }

22

23

    @Override

24

    public void readFields(DataInput in) throws IOException {

25

      // TODO Auto-generated method stub

26

      this.accout=in.readUTF();

27

      this.incom=in.readDouble();

28

      this.zhichu=in.readDouble();

29

      this.jieyu=in.readDouble();

30

    }

31

32

    @Override

33

    public int compareTo(InfoBean infoBean) {

34

      if(this.incom == infoBean.getIncom()){

35

        return this.zhichu > infoBean.getZhichu() ? 1 : -1;

36

      }else{

37

        return this.incom > infoBean.getIncom() ? -1 : 1;

38

      }

39

    }

40

41

    public String getAccout() {

42

      return accout;

43

    }

44

45

    public void setAccout(String accout) {

46

      this.accout = accout;

47

    }

48

49

    public double getIncom() {

50

      return incom;

51

    }

52

53

    public void setIncom(double incom) {

54

      this.incom = incom;

55

    }

56

57

    public double getZhichu() {

58

      return zhichu;

59

    }

60

61

    public void setZhichu(double zhichu) {

62

      this.zhichu = zhichu;

63

    }

64

65

    public double getJieyu() {

66

      return jieyu;

67

    }

68

69

    public void setJieyu(double jieyu) {

70

      this.jieyu = jieyu;

71

    }

72

73

    @Override

74

    public String toString() {

75

      return incom +"	" + zhichu +"	" + jieyu;

76

    }

77

78

    public void set(String accout,double incom,double zhichu){

79

      this.accout=accout;

80

      this.incom=incom;

81

      this.zhichu=zhichu;

82

      this.jieyu=incom - zhichu;

83

    }

84

  }

 

 

 

SumStep类

 

  import java.io.IOException;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.io.LongWritable;
  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;

  public class SumStep {

    public static void main(String[] args) throws Exception {
      // TODO Auto-generated method stub
      Job job=Job.getInstance(new Configuration());

      job.setJarByClass(SumStep.class);

      job.setMapperClass(SumMapper.class);
      job.setMapOutputKeyClass(Text.class);
      job.setMapOutputValueClass(InfoBean.class);
      FileInputFormat.setInputPaths(job, args[0]);

      job.setReducerClass(sumReducer.class);
      job.setOutputKeyClass(Text.class);
      job.setOutputValueClass(InfoBean.class);
      FileOutputFormat.setOutputPath(job, new Path(args[1]));

      job.waitForCompletion(true);
    }
       public static class SumMapper extends Mapper<LongWritable, Text, Text, InfoBean>{

      private Text k2 = new Text();
      private InfoBean v2 = new InfoBean();
           
      @Override
      protected void map(LongWritable key, Text value, 
      Mapper<LongWritable, Text, Text, InfoBean>.Context context)
          throws IOException, InterruptedException {
        String line=value.toString();
        String[] hang=line.split("	");
        String accout=hang[0];
        double incom=Double.parseDouble(hang[1]);
        double zhichu=Double.parseDouble(hang[2]);

        k2.set(accout);
        v2.set(accout, incom, zhichu);
        context.write(k2, v2);
      }

    }
     public static class sumReducer extends Reducer<Text, InfoBean, Text, InfoBean>{
        private InfoBean v3 = new InfoBean();
         
      @Override
      protected void reduce(Text k2, Iterable<InfoBean> v2, 
      Reducer<Text, InfoBean, Text, InfoBean>.Context context)
          throws IOException, InterruptedException {
        double sumIncom = 0;
        double sumZhichu = 0;
        for(InfoBean infoBean : v2){
          sumIncom += infoBean.getIncom();
          sumZhichu += infoBean.getZhichu();
        }
        v3.set("", sumIncom, sumZhichu);
        context.write(k2, v3);
      }
    }
  }

 

 

 

x

 

 

 

 

 

1

  import java.io.IOException;

2

  import org.apache.hadoop.conf.Configuration;

3

  import org.apache.hadoop.fs.Path;

4

  import org.apache.hadoop.io.LongWritable;

5

  import org.apache.hadoop.io.Text;

6

  import org.apache.hadoop.mapreduce.Job;

7

  import org.apache.hadoop.mapreduce.Mapper;

8

  import org.apache.hadoop.mapreduce.Reducer;

9

  import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;

10

  import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

11

12

  public class SumStep {

13

14

    public static void main(String[] args) throws Exception {

15

      // TODO Auto-generated method stub

16

      Job job=Job.getInstance(new Configuration());

17

18

      job.setJarByClass(SumStep.class);

19

20

      job.setMapperClass(SumMapper.class);

21

      job.setMapOutputKeyClass(Text.class);

22

      job.setMapOutputValueClass(InfoBean.class);

23

      FileInputFormat.setInputPaths(job, args[0]);

24

25

      job.setReducerClass(sumReducer.class);

26

      job.setOutputKeyClass(Text.class);

27

      job.setOutputValueClass(InfoBean.class);

28

      FileOutputFormat.setOutputPath(job, new Path(args[1]));

29

30

      job.waitForCompletion(true);

31

    }

32

       public static class SumMapper extends Mapper<LongWritable, Text, Text, InfoBean>{

33

34

      private Text k2 = new Text();

35

      private InfoBean v2 = new InfoBean();

36

37

      @Override

38

      protected void map(LongWritable key, Text value, 

39

      Mapper<LongWritable, Text, Text, InfoBean>.Context context)

40

          throws IOException, InterruptedException {

41

        String line=value.toString();

42

        String[] hang=line.split("	");

43

        String accout=hang[0];

44

        double incom=Double.parseDouble(hang[1]);

45

        double zhichu=Double.parseDouble(hang[2]);

46

47

        k2.set(accout);

48

        v2.set(accout, incom, zhichu);

49

        context.write(k2, v2);

50

      }

51

52

    }

53

     public static class sumReducer extends Reducer<Text, InfoBean, Text, InfoBean>{

54

        private InfoBean v3 = new InfoBean();

55

56

      @Override

57

      protected void reduce(Text k2, Iterable<InfoBean> v2, 

58

      Reducer<Text, InfoBean, Text, InfoBean>.Context context)

59

          throws IOException, InterruptedException {

60

        double sumIncom = 0;

61

        double sumZhichu = 0;

62

        for(InfoBean infoBean : v2){

63

          sumIncom += infoBean.getIncom();

64

          sumZhichu += infoBean.getZhichu();

65

        }

66

        v3.set("", sumIncom, sumZhichu);

67

        context.write(k2, v3);

68

      }

69

    }

70

  }

 

 

SortStep类

  import java.io.IOException;
  import org.apache.hadoop.conf.Configuration;
  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;
  public class SortStep {

    public static void main(String[] args) throws Exception {
      // TODO Auto-generated method stub
      Job job=Job.getInstance(new Configuration());

      job.setJarByClass(SortStep.class);

      job.setMapperClass(SortMapper.class);
      job.setMapOutputKeyClass(InfoBean.class);
      job.setMapOutputValueClass(NullWritable.class);
      FileInputFormat.setInputPaths(job, new Path(args[0]));

      job.setReducerClass(SortReducer.class);
      job.setOutputKeyClass(Text.class);
      job.setOutputValueClass(InfoBean.class);
      FileOutputFormat.setOutputPath(job, new Path(args[1]));

      job.waitForCompletion(true);
    }

    public static class SortMapper extends 
    Mapper<LongWritable, Text, InfoBean, NullWritable>{

      private InfoBean k2 = new InfoBean();

      @Override
      protected void map(LongWritable key, Text value,
          Mapper<LongWritable, Text, InfoBean, NullWritable>.Context context)
              throws IOException, InterruptedException {
        String line = value.toString();
        String[] hang=line.split("	");
        String accout = hang[0];
        double incom = Double.parseDouble(hang[1]);
        double zhichu = Double.parseDouble(hang[2]);

        k2.set(accout, incom, zhichu);

        context.write(k2,NullWritable.get());
      }

    }
    public static class SortReducer extends Reducer<InfoBean, NullWritable, Text, InfoBean>{

      private Text k3=new Text();
      @Override
      protected void reduce(InfoBean k2, Iterable<NullWritable> v2,
          Reducer<InfoBean, NullWritable, Text, InfoBean>.Context context) 
          throws IOException, InterruptedException {
        k3.set(k2.getAccout());
        context.write(k3, k2);
      }

    }
  }

 

 

 

 

 

 

 

 

 

1

  import java.io.IOException;

2

  import org.apache.hadoop.conf.Configuration;

3

  import org.apache.hadoop.fs.Path;

4

  import org.apache.hadoop.io.LongWritable;

5

  import org.apache.hadoop.io.NullWritable;

6

  import org.apache.hadoop.io.Text;

7

  import org.apache.hadoop.mapreduce.Job;

8

  import org.apache.hadoop.mapreduce.Mapper;

9

  import org.apache.hadoop.mapreduce.Reducer;

10

  import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;

11

  import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

12

  public class SortStep {

13

14

    public static void main(String[] args) throws Exception {

15

      // TODO Auto-generated method stub

16

      Job job=Job.getInstance(new Configuration());

17

18

      job.setJarByClass(SortStep.class);

19

20

      job.setMapperClass(SortMapper.class);

21

      job.setMapOutputKeyClass(InfoBean.class);

22

      job.setMapOutputValueClass(NullWritable.class);

23

      FileInputFormat.setInputPaths(job, new Path(args[0]));

24

25

      job.setReducerClass(SortReducer.class);

26

      job.setOutputKeyClass(Text.class);

27

      job.setOutputValueClass(InfoBean.class);

28

      FileOutputFormat.setOutputPath(job, new Path(args[1]));

29

30

      job.waitForCompletion(true);

31

    }

32

33

    public static class SortMapper extends 

34

    Mapper<LongWritable, Text, InfoBean, NullWritable>{

35

36

      private InfoBean k2 = new InfoBean();

37

38

      @Override

39

      protected void map(LongWritable key, Text value,

40

          Mapper<LongWritable, Text, InfoBean, NullWritable>.Context context)

41

              throws IOException, InterruptedException {

42

        String line = value.toString();

43

        String[] hang=line.split("	");

44

        String accout = hang[0];

45

        double incom = Double.parseDouble(hang[1]);

46

        double zhichu = Double.parseDouble(hang[2]);

47

48

        k2.set(accout, incom, zhichu);

49

50

        context.write(k2,NullWritable.get());

51

      }

52

53

    }

54

    public static class SortReducer extends Reducer<InfoBean, NullWritable, Text, InfoBean>{

55

56

      private Text k3=new Text();

57

      @Override

58

      protected void reduce(InfoBean k2, Iterable<NullWritable> v2,

59

          Reducer<InfoBean, NullWritable, Text, InfoBean>.Context context) 

60

          throws IOException, InterruptedException {

61

        k3.set(k2.getAccout());

62

        context.write(k3, k2);

63

      }

64

65

    }

66

  }