自定义组件Partitioner- 根据不同省份统计手机流量

野性酷女 2022-02-26 01:46 207阅读 0赞

### 自定义组件Partitioner- 根据不同省份统计手机流量 ###

*  需求
 *  思路
 *  实现
 *   *  JavaBean
     *  自定义Partitioner
     *  Mapper
     *  reduce
 *  结果!\[在这里插入图片描述\](https://img-blog.csdnimg.cn/20190328170806291.png?x-oss-process=image/watermark,type\_ZmFuZ3poZW5naGVpdGk,shadow\_10,text\_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2pqa2FuZ18=,size\_16,color\_FFFFFF,t\_70)

> 默认情况下，Mapreduce会将map输出的kv对，按照相同的key分组，然后分发给reducetask（按照key.hashCode() % (reducetask数) 分发 ）

# 需求 #

> 原始数据不变，依然是[\[原始数据地址\]][Link 1]。如果让根据不同省份分别输出到不同的文件中，该怎么办？

# 思路 #

> 既然Mapreduce是按照key.hashCode() % (reducetask数) 的规则分发数据的，那么，如果我们可以改变这个规则，自定义一个规则，同一个省的数据分发到同一个reducetask，就能实现需求。

# 实现 #

## JavaBean ##

public class Traffic implements Writable{
            private String phone;
            private int upStream;
            private int downStream;
            private int total;
            public Traffic() {
            }
            public void setTraffic(String phone, int upStream, int downStream) {
                    this.phone = phone;
                    this.upStream = upStream;
                    this.downStream = downStream;
                    this.total = upStream + downStream;
            }
            public String getPhone() {
                    return phone;
            }
            public void setPhone(String phone) {
                    this.phone = phone;
            }
            public int getUpStream() {
                    return upStream;
            }
            public void setUpStream(int upStream) {
                    this.upStream = upStream;
            }
            public int getDownStream() {
                    return downStream;
            }
            public void setDownStream(int downStream) {
                    this.downStream = downStream;
            }
            public int getTotal() {
                    return total;
            }
            public void setTotal(int total) {
                    this.total = total;
            }
    
            @Override
            public void readFields(DataInput in) throws IOException {
                    upStream = in.readInt();
                    downStream = in.readInt();
                    total = in.readInt();
            }
    
            @Override
            public void write(DataOutput out) throws IOException {
                    out.writeInt(upStream);
                    out.writeInt(downStream);
                    out.writeInt(total);
            }
            @Override
            public String toString() {
                    return "[phone=" + phone + ", upStream=" + upStream + ", downStream=" + downStream + ", total=" + total + "]";
            }
    }

## 自定义Partitioner ##

public class SelfPartitioner extends Partitioner<Text, Traffic> {
    
            private static Map<String, Integer> provinces = new HashedMap();
    		//模拟数据
            static {
                    provinces.put("136", 0);
                    provinces.put("137", 1);
                    provinces.put("138", 2);
                    provinces.put("139", 3);
    
            }
    
            @Override
            public int getPartition(Text key, Traffic value, int arg2) {
                    String prefix = key.toString().substring(0, 3);
                    Integer integer = provinces.get(prefix);
                    return integer == null ? 4 : integer;
            }
    
    }

## Mapper ##

public class TrafficSumMapper extends Mapper<LongWritable, Text, Text, Traffic>{
    
            Traffic traffic = new Traffic();
            Text k = new Text();
    
            @Override
            protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
                    String line = value.toString();
                    String[] fileds = line.split("\t");
                    if(fileds.length!=11) return;
    
                    int upStream = Integer.parseInt(fileds[8]);
                    int downStream = Integer.parseInt(fileds[9]);
    
                    traffic.setTraffic(fileds[1], upStream, downStream);
                    k.set(fileds[1]);
                    context.write(k, traffic);
            }
    
    }

## reduce ##

public class TrafficSumReduce extends Reducer<Text, Traffic, Text, Traffic>{
    
    
    
            @Override
            protected void reduce(Text key, Iterable<Traffic> values, Context context) throws IOException, InterruptedException {
                    Traffic t = new Traffic();
                    int totalUpStream = 0;
                    int totalDownStream = 0;
                    int total = 0;
                    for (Traffic traffic : values) {
                            totalUpStream += traffic.getUpStream();
                            totalDownStream += traffic.getDownStream();
                            total += traffic.getTotal();
                    }
                    t.setTraffic(key.toString(), totalUpStream, totalDownStream);
                    context.write(key, t);
            }
    }

# 结果![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2pqa2FuZ18_size_16_color_FFFFFF_t_70] #

> 生成了五个文件，每个文件存放不同省份的手机号

[Link 1]: https://blog.csdn.net/jjkang_/article/details/88870910
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2pqa2FuZ18_size_16_color_FFFFFF_t_70]: /images/20220226/9efd2456e0f94cdabbc4d6a3dbdc0ad9.png