本地MapReduce案例分享

悠悠 2021-12-14 04:39 323阅读 0赞

没有接触的时候，以为MapReduce只能通过远程Hadoop虚拟机才能运行，学习了相关课程之后，发现这种计算也可以在本地运行，只是在部署的时候需要部署到远程服务器上就行了  
引入的pom.xml

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.7</maven.compiler.source>
        <maven.compiler.target>1.7</maven.compiler.target>
        <hadoop.version>2.6.0-cdh5.15.1</hadoop.version>
      </properties>
    
      <repositories>
        <repository>
          <id>cloudera</id>
          <url>https://repository.cloudera.com/artifactory/cloudera-repos/</url>
        </repository>
      </repositories>
      <dependencies>
        <dependency>
          <groupId>org.apache.hadoop</groupId>
          <artifactId>hadoop-client</artifactId>
          <version>${hadoop.version}</version>
        </dependency>
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.10</version>
          <scope>test</scope>
        </dependency>
      </dependencies>

## WordCount词频统计案例 ##

wordcount是最经典的案例，实现如下

### Mapper ###

import org.apache.hadoop.io.IntWritable;
    import org.apache.hadoop.io.LongWritable;
    import org.apache.hadoop.io.Text;
    import org.apache.hadoop.mapreduce.Mapper;
    
    import java.io.IOException;
    
    public class WordCountMapper extends Mapper<LongWritable, Text,Text, IntWritable>{
    
        @Override
        protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
            //super.map(key, value, context);
            String[] words = value.toString().split("\t");
            for (String word:words){
                context.write(new Text(word),new IntWritable(1));
            }
        }
    }

### Reducer ###

public class WordCountReducer extends Reducer<Text, IntWritable,Text,IntWritable> {
    
        @Override
        protected void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException {
            //super.reduce(key, values, context);
            int count=0;
            Iterator<IntWritable> iterator = values.iterator();
            while(iterator.hasNext()){
                IntWritable value = iterator.next();
                count+=value.get();
            }
            context.write(key,new IntWritable(count));
        }
    }

### Driver ###

public  static  void  main (String[] args) throws Exception {
            Configuration configuration = new Configuration();
            Job job = Job.getInstance(configuration);
    
            job.setJarByClass(WordCountDriver.class);
    
            job.setMapperClass(WordCountMapper.class);
            job.setReducerClass(WordCountReducer.class);
    
            job.setMapOutputKeyClass(Text.class);
            job.setMapOutputValueClass(IntWritable.class);
    
            FileInputFormat.setInputPaths(job,new Path("input"));
            FileOutputFormat.setOutputPath(job,new Path("output"));
    
            boolean result = job.waitForCompletion(true);
            System.exit(result?0:1);
    
        }

在项目目录下创建input文件，并使用词频文件

hello	world	welcome
    Hello	Welcome

运行之后，可以得到结果

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly96aGFvemhlbi5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70]

## 流量统计分析 ##

### 自定义类 ###

import org.apache.hadoop.io.Writable;
    
    import java.io.DataInput;
    import java.io.DataOutput;
    import java.io.IOException;
    
    public class Access  implements Writable {
        private   String phone;
        private long up;
        private  long down;
        private  long sum;
    
        public String getPhone() {
            return phone;
        }
    
        public void setPhone(String phone) {
            this.phone = phone;
        }
    
        public Access() {
        }
    
        public Access(String phone, long up, long down) {
            this.phone = phone;
            this.up = up;
            this.down = down;
            this.sum = up+down;
        }
    
        @Override
        public void write(DataOutput dataOutput) throws IOException {
    
            dataOutput.writeUTF(phone);
            dataOutput.writeLong(up);
            dataOutput.writeLong(down);
            dataOutput.writeLong(sum);
        }
    
        @Override
        public String toString() {
            return  phone  +
                    "," + up +
                    "," + down +
                    "," + sum ;
        }
    
        @Override
        public void readFields(DataInput in) throws IOException {
            //注意与write方法的顺序匹配
            this.phone = in.readUTF();
            this.up = in.readLong();
            this.down = in.readLong();
            this.sum = in.readLong();
    
        }
    
        public long getUp() {
            return up;
        }
    
        public void setUp(long up) {
            this.up = up;
        }
    
        public long getDown() {
            return down;
        }
    
        public void setDown(long down) {
            this.down = down;
        }
    
        public long getSum() {
            return sum;
        }
    
        public void setSum(long sum) {
            this.sum = sum;
        }
    }

### Mapper ###

import org.apache.hadoop.io.LongWritable;
    import org.apache.hadoop.io.Text;
    import org.apache.hadoop.mapreduce.Mapper;
    
    import java.io.IOException;
    
    public class AccessMapper extends Mapper<LongWritable, Text,Text,Access> {
        @Override
        protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
            String[] lines =value.toString().split("\t");
            String phone = lines[1];
            long up = Long.parseLong(lines[lines.length-3]);
            long down =Long.parseLong(lines[lines.length-2]);
            context.write(new Text(phone),new Access(phone,up,down));
    
        }
    }

### Reducer ###

import org.apache.hadoop.io.Text;
    import org.apache.hadoop.mapreduce.Reducer;
    
    import java.io.IOException;
    
    public class AccessReducer extends Reducer<Text,Access,Text,Access> {
        @Override
        protected void reduce(Text key, Iterable<Access> values, Context context) throws IOException, InterruptedException {
    
            long ups = 0;
            long downs = 0;
            for (Access access:values){
                ups+= access.getUp();
                downs+= access.getDown();
            }
            context.write(key,new Access(key.toString(),ups,downs));
        }
    }

### Driver ###

public class AccessDriver {
        public static void main(String[] args) throws  Exception{
            Configuration configuration = new Configuration();
            Job job = Job.getInstance(configuration);
    
            job.setJarByClass(AccessDriver.class);
    
            job.setMapperClass(AccessMapper.class);
            job.setReducerClass(AccessReducer.class);
    
            job.setMapOutputKeyClass(Text.class);
            job.setMapOutputValueClass(Access.class);
    
            job.setOutputKeyClass(Text.class);
            job.setOutputValueClass(Access.class);
    
            FileInputFormat.setInputPaths(job,new Path("access/input"));
            FileOutputFormat.setOutputPath(job,new Path("access/output"));
    
            boolean result = job.waitForCompletion(true);
            System.exit(result?0:1);
        }
    }

输入的文件内容

1363157985066 	13726230503	00-FD-07-A4-72-B8:CMCC	120.196.100.82	i02.c.aliimg.com		24	27	2481	24681	200
    1363157995052 	13826544101	5C-0E-8B-C7-F1-E0:CMCC	120.197.40.4			4	0	264	0	200
    1363157991076 	13926435656	20-10-7A-28-CC-0A:CMCC	120.196.100.99			2	4	132	1512	200
    1363154400022 	13926251106	5C-0E-8B-8B-B1-50:CMCC	120.197.40.4			4	0	240	0	200
    1363157993044 	18211575961	94-71-AC-CD-E6-18:CMCC-EASY	120.196.100.99	iface.qiyi.com	视频网站	15	12	1527	2106	200
    1363157995074 	84138413	5C-0E-8B-8C-E8-20:7DaysInn	120.197.40.4	122.72.52.12		20	16	4116	1432	200
    1363157993055 	13560439658	C4-17-FE-BA-DE-D9:CMCC	120.196.100.99			18	15	1116	954	200
    1363157995033 	15920133257	5C-0E-8B-C7-BA-20:CMCC	120.197.40.4	sug.so.360.cn	信息安全	20	20	3156	2936	200
    1363157983019 	13719199419	68-A1-B7-03-07-B1:CMCC-EASY	120.196.100.82			4	0	240	0	200
    1363157984041 	13660577991	5C-0E-8B-92-5C-20:CMCC-EASY	120.197.40.4	s19.cnzz.com	站点统计	24	9	6960	690	200
    1363157973098 	15013685858	5C-0E-8B-C7-F7-90:CMCC	120.197.40.4	rank.ie.sogou.com	搜索引擎	28	27	3659	3538	200
    1363157986029 	15989002119	E8-99-C4-4E-93-E0:CMCC-EASY	120.196.100.99	www.umeng.com	站点统计	3	3	1938	180	200
    1363157992093 	13560439658	C4-17-FE-BA-DE-D9:CMCC	120.196.100.99			15	9	918	4938	200
    1363157986041 	13480253104	5C-0E-8B-C7-FC-80:CMCC-EASY	120.197.40.4			3	3	180	180	200
    1363157984040 	13602846565	5C-0E-8B-8B-B6-00:CMCC	120.197.40.4	2052.flash2-http.qq.com	综合门户	15	12	1938	2910	200
    1363157995093 	13922314466	00-FD-07-A2-EC-BA:CMCC	120.196.100.82	img.qfc.cn		12	12	3008	3720	200
    1363157982040 	13502468823	5C-0A-5B-6A-0B-D4:CMCC-EASY	120.196.100.99	y0.ifengimg.com	综合门户	57	102	7335	110349	200
    1363157986072 	18320173382	84-25-DB-4F-10-1A:CMCC-EASY	120.196.100.99	input.shouji.sogou.com	搜索引擎	21	18	9531	2412	200
    1363157990043 	13925057413	00-1F-64-E1-E6-9A:CMCC	120.196.100.55	t3.baidu.com	搜索引擎	69	63	11058	48243	200
    1363157988072 	13760778710	00-FD-07-A4-7B-08:CMCC	120.196.100.82			2	2	120	120	200
    1363157985066 	13726238888	00-FD-07-A4-72-B8:CMCC	120.196.100.82	i02.c.aliimg.com		24	27	2481	24681	200
    1363157993055 	13560436666	C4-17-FE-BA-DE-D9:CMCC	120.196.100.99			18	15	1116	954	200
    1363157985066 	13726238888	00-FD-07-A4-72-B8:CMCC	120.196.100.82	i02.c.aliimg.com		24	27	10000	20000	200

输出内容

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly96aGFvemhlbi5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 1]

本文参考  
[Hadoop基础与电商行为日志分析 新手入门大数据][Hadoop_]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly96aGFvemhlbi5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70]: /images/20211213/fe5dbc515f48490b88e05c224e4726f9.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly96aGFvemhlbi5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 1]: /images/20211213/78778a7d69f44eb4ba14c4cb1e142557.png
[Hadoop_]: https://coding.imooc.com/learn/list/301.html