前言
直通车之前写了一个全排序,使用的是RawComparator来实现!这次则使用WritableComparable实现!
数据源
tel up down total
13470253144 180 180 360
13509468723 7335 110349 117684
13560439638 918 4938 5856
13568436656 3597 25635 29232
13590439668 1116 954 2070
13630577991 6960 690 7650
13682846555 1938 2910 4848
13729199489 240 0 240
13736230513 2481 24681 27162
13768778790 120 120 240
13846544121 264 0 264
13956435636 132 1512 1644
13966251146 240 0 240
13975057813 11058 48243 59301
13992314666 3008 3720 6728
15043685818 3659 3538 7197
15910133277 3156 2936 6092
15959002129 1938 180 2118
18271575951 1527 2106 3633
18390173782 9531 2412 11943
84188413 4116 1432 5548
13560439639 918 4938 5856
13560439631 918 4938 5856
13560439632 918 4938 5856
13560439633 918 4938 5856
Bean
package com.zhengkw.topn;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.WritableComparable;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
/**
* @ClassName:FlowBean
* @author: zhengkw
* @description:
* @date: 20/02/27上午 9:51
* @version:1.0
* @since: jdk 1.8
*/
public class FlowBean implements WritableComparable<FlowBean> {
//上行
private long upFlow;
// 下行
private long downFlow;
// 总量
private long totalFlow;
//序列化
@Override
public void write(DataOutput out) throws IOException {
out.writeLong(upFlow);
out.writeLong(downFlow);
out.writeLong(totalFlow);
}
//反序列化
@Override
public void readFields(DataInput in) throws IOException {
this.upFlow = in.readLong();
this.downFlow = in.readLong();
this.totalFlow = in.readLong();
}
public void setUpFlow(long upFlow) {
this.upFlow = upFlow;
}
public void setDownFlow(long downFlow) {
this.downFlow = downFlow;
}
public void setTotalFlow(long totalFlow) {
this.totalFlow = totalFlow;
}
public long getUpFlow() {
return upFlow;
}
public long getDownFlow() {
return downFlow;
}
public long getTotalFlow() {
return totalFlow;
}
public FlowBean() {
super();
}
/**
* @param o 比较器被调用时 keyin作为参数传递
* @descrption:只比较总流量
* @return: int
* @date: 20/02/27 上午 10:01
* @author: zhengkw
*/
@Override
public int compareTo(FlowBean o) {
return this.totalFlow > o.getTotalFlow() ? -1 : 1;
}
@Override
public String toString() {
return
upFlow + "\t" + downFlow + "\t" + totalFlow;
}
}
Mapper
package com.zhengkw.topn;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import java.io.IOException;
/**
* @ClassName:TopNMapper
* @author: zhengkw
* @description: 按照手机号求和以后总流量倒序排序(mapper截取封装)
* @date: 20/02/27上午 9:49
* @version:1.0
* @since: jdk 1.8
*/
public class TopNMapper extends Mapper<LongWritable, Text, FlowBean, Text> {
FlowBean k = new FlowBean();
//tel
Text v = new Text();
//13509468723 117684 110349 228033
@Override
protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
String line = value.toString();
String[] val = line.split("\t");
v.set(val[0]);
k.setUpFlow(Long.parseLong(val[1]));
k.setDownFlow(Long.parseLong(val[2]));
k.setTotalFlow(Long.parseLong(val[3]));
context.write(k, v);
}
}
reduce
package com.zhengkw.topn;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import java.io.IOException;
/**
* @ClassName:TopNMapper
* @author: zhengkw
* @description: 按照手机号求和以后总流量倒序排序(mapper截取封装)
* @date: 20/02/27上午 9:49
* @version:1.0
* @since: jdk 1.8
*/
public class TopNMapper extends Mapper<LongWritable, Text, FlowBean, Text> {
FlowBean k = new FlowBean();
//tel
Text v = new Text();
//13509468723 117684 110349 228033
@Override
protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
String line = value.toString();
String[] val = line.split("\t");
v.set(val[0]);
k.setUpFlow(Long.parseLong(val[1]));
k.setDownFlow(Long.parseLong(val[2]));
k.setTotalFlow(Long.parseLong(val[3]));
context.write(k, v);
}
}
driver
package com.zhengkw.topn;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import java.io.IOException;
/**
* @ClassName:TopNDriver
* @author: zhengkw
* @description: 最后一次手写
* @date: 20/02/27上午 10:50
* @version:1.0
* @since: jdk 1.8
*/
public class TopNDriver {
public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
// 输入路径
Path inputPath = new Path("f:/output1");
// 输出路径
Path outputPath = new Path("f:/output2");
Configuration conf = new Configuration();
//判断输出路径是否已经存在 存在则删除
FileSystem fs = FileSystem.get(conf);
if (fs.exists(outputPath)) {
fs.delete(outputPath, true);
}
// 创建job
Job job = Job.getInstance(conf);
//设置3个类
job.setJarByClass(TopNDriver.class);
job.setMapperClass(TopNMapper.class);
job.setReducerClass(TopNReducer.class);
//设置2个阶段的K V类
job.setMapOutputKeyClass(FlowBean.class);
job.setMapOutputValueClass(Text.class);
//指定最终输出的 KV 类
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(FlowBean.class);
//设置输入输出路径
FileInputFormat.setInputPaths(job, inputPath);
FileOutputFormat.setOutputPath(job, outputPath);
//提交job true打印job信息 获取返回值退出程序
boolean result = job.waitForCompletion(true);
System.exit(result ? 0 : 1);
}
}
总结
/**
* @param o 比较器被调用时 keyin作为参数传递
* @descrption:只比较总流量
* @return: int
* @date: 20/02/27 上午 10:01
* @author: zhengkw
*/
@Override
public int compareTo(FlowBean o) {
return this.totalFlow > o.getTotalFlow() ? -1 : 1;
}
因Mapper的KEYOUT为自定义的bean,所以需要重写comparaTo()这样才能让2个对象进行比较大小!