19-hadoop-fof好友推荐

好友推荐的案例, 需要两个job, 第一个进行好友关系度计算, 第二个job将计算的关系进行推荐

1, fof关系类

package com.wenbronk.friend;

import org.apache.hadoop.io.Text;

/**
 * 定义fof关系
 * @author root
 *
 */
public class Fof extends Text{

    public Fof() {
        super();
    }
    
    /**'
     * 不论谁在前,返回一致的顺序
     * @param a
     * @param b
     */
    public Fof(String a, String b) {
        super(getFof(a, b));
    }
    
    /**
     * 按字典顺序排序, 保证两个fof为同一组输出
     * @param a
     * @param b
     * @return
     */
    public static String getFof(String a, String b) {
        int r = a.compareTo(b);
        if (r < 0) {
            return a + "	" + b;
        }else {
            return b + "	" + a;
        }
            
    }
    
    
    
}

2, user类

package com.wenbronk.friend;

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

import org.apache.hadoop.io.WritableComparable;

public class User implements WritableComparable<User>{

    private String uname;
    private int friedsCount;
    
    public String getUname() {
        return uname;
    }

    public void setUname(String uname) {
        this.uname = uname;
    }

    public int getFriedsCount() {
        return friedsCount;
    }

    public void setFriedsCount(int friedsCount) {
        this.friedsCount = friedsCount;
    }
    
    public User() {
        super();
    }

    public User(String uname, int friedsCount) {
        super();
        this.uname = uname;
        this.friedsCount = friedsCount;
    }

    @Override
    public void readFields(DataInput arg0) throws IOException {
        this.uname = arg0.readUTF();
        this.friedsCount = arg0.readInt();
    }

    @Override
    public void write(DataOutput arg0) throws IOException {
        arg0.writeUTF(uname);
        arg0.writeInt(friedsCount);
    }

    @Override
    public int compareTo(User o) {
        int result = this.uname.compareTo(o.getUname());
        if (result == 0) {
            return Integer.compare(this.friedsCount, o.getFriedsCount());
        }
        return result;
    }
    
}

3, sort

package com.wenbronk.friend;

import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.io.WritableComparator;

/**
 * 排序
 * @author root
 *
 */
public class FofSort extends WritableComparator {

    public FofSort() {
        super(User.class, true);
    }
    
    @Override
    public int compare(WritableComparable a, WritableComparable b) {
        User user1 = (User) a;
        User user2 = (User) b;
        
        int compareTo = user1.getUname().compareTo(user2.getUname());
        if (compareTo == 0) {
            compareTo = Integer.compare(user1.getFriedsCount(), user2.getFriedsCount());
        }
        return compareTo;
    }
    
}

4, group

package com.wenbronk.friend;

import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.io.WritableComparator;

/**
 * 自定义分组
 * @author root
 *
 */
public class FofGroup extends WritableComparator {

    public FofGroup() {
        super(User.class, true);
    }
    
    @Override
    public int compare(WritableComparable a, WritableComparable b) {
        User u1 = (User) a;
        User u2 = (User) b;
        return u1.getUname().compareTo(u2.getUname());
    }
    
}

5, job

package com.wenbronk.friend;

import java.io.IOException;

import org.apache.commons.lang.StringUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
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.input.KeyValueTextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

/**
 * 1个mapreduce找到所有的fof关系 第二个mapreduce执行排序
 * 
 * @author root
 */
public class RunJob {

    public static void main(String[] args) throws IOException {
        Configuration configuration = new Configuration();
//        configuration.set("mapred.jar", "C:/Users/wenbr/Desktop/fof.jar");
        
        // 本地运行
        configuration.set("fs.default", "hdfs://wenbronk.hdfs.com:8020    ");
        configuration.set("yarn.resourcemanager", "hdfs://192.168.208.106");
        
        
        if (runFindFof(configuration)) {
            // 根据foffind进行排序
            run2(configuration);
        }
        
    }

    /**
     * 找到所有的fof关系
     * @throws IOException 
     */
    private static boolean runFindFof(Configuration conf) throws IOException {
        try {
            FileSystem fs = FileSystem.get(conf);
            Job job = Job.getInstance(conf);
            job.setJobName("friend");
            
            job.setJarByClass(RunJob.class);
            job.setMapperClass(FofMapper.class);
            job.setReducerClass(FofReduce.class);
            job.setMapOutputKeyClass(Fof.class);
            job.setMapOutputValueClass(IntWritable.class);
            
//            job.setJar("C:/Users/wenbr/Desktop/friend.jar");
            
            job.setInputFormatClass(KeyValueTextInputFormat.class);
//            FileInputFormat.addInputPath(job, new Path("/usr/friend.txt"));
            FileInputFormat.addInputPath(job, new Path("E:\sxt\1-MapReduce\data\friend.txt"));
            
            Path path = new Path("/root/usr/fof/f1");
            if (fs.exists(path)) {
                fs.delete(path, true);
            }
            FileOutputFormat.setOutputPath(job, path);            
            return job.waitForCompletion(true);
        }catch(Exception e) {
            e.printStackTrace();
        }
        return false;
    }
    static class FofMapper extends Mapper<Text, Text, Fof, IntWritable> {
        @Override
        protected void map(Text key, Text value, Mapper<Text, Text, Fof, IntWritable>.Context context)
                throws IOException, InterruptedException {
            // super.map(key, value, context);
            String user = key.toString();
            String[] frieds = StringUtils.split(value.toString(), '	');

            for (int i = 0; i < frieds.length; i++) {
                String f1 = frieds[i];
                // 去掉是直接好友的, 按组输出, 如果组中有value=0 的, 整组数据舍弃
                context.write(new Fof(user, f1), new IntWritable(0));
                for (int j = i + 1; j < frieds.length; j++) {
                    String f2 = frieds[j];

                    Fof fof = new Fof(f1, f2);
                    context.write(fof, new IntWritable(1));
                }
            }
        }
    }
    static class FofReduce extends Reducer<Fof, IntWritable, Fof, IntWritable> {
        @Override
        protected void reduce(Fof arg0, Iterable<IntWritable> arg1,
                Reducer<Fof, IntWritable, Fof, IntWritable>.Context arg2) throws IOException, InterruptedException {
            boolean flag = false;
            int sum = 0;
            for (IntWritable count : arg1) {
                // 值有0的, 整组数据舍弃
                if (count.get() == 0) {
                    flag = true;
                    break;
                } else {
                    sum += count.get();
                }
            }
            
            if (!flag) {
                arg2.write(arg0, new IntWritable(sum));
            }
        }
    }
    
    /**
     * 向用户推荐好友
     * @param config
     */
    public static void run2(Configuration config) {
        try {
            FileSystem fileSystem = FileSystem.get(config);
            Job job = Job.getInstance(config);
            
            job.setJobName("fof2");
            
            job.setMapperClass(SortMapper.class);
            job.setReducerClass(SortReduce.class);
            job.setSortComparatorClass(FofSort.class);
            job.setGroupingComparatorClass(FofGroup.class);
            
            job.setMapOutputKeyClass(User.class);
            job.setMapOutputValueClass(User.class);
            
            job.setInputFormatClass(KeyValueTextInputFormat.class);
            
            // 设置MR执行的输入文件
            FileInputFormat.addInputPath(job, new Path("/usr/output/f1"));
            
            // 设置输出文件, 文件不可存在
            Path path = new Path("/root/usr/fof/f2");
            if (fileSystem.exists(path)) {
                fileSystem.delete(path, true);
            }
            
            FileOutputFormat.setOutputPath(job, path);
            
            boolean f = job.waitForCompletion(true);
            if (f) {
                System.out.println("job, 成功执行");
            }
            
        }catch (Exception e) {
            e.printStackTrace();
        }
    }
    static class SortMapper extends Mapper<Text, Text, User, User> {
        @Override
        protected void map(Text key, Text value, Mapper<Text, Text, User, User>.Context context)
                throws IOException, InterruptedException {
            String[] args = StringUtils.split(value.toString(), '	');
            String other = args[0];
            int friendsCount = Integer.parseInt(args[1]);
            // 输出两次, 同时给fof两个用户推荐好友
            context.write(new User(key.toString(), friendsCount), new User(other, friendsCount));
            context.write(new User(other, friendsCount), new User(key.toString(), friendsCount));
        }
    }
    static class SortReduce extends Reducer<User, User, Text, Text>{
        @Override
        protected void reduce(User arg0, Iterable<User> arg1, Reducer<User, User, Text, Text>.Context arg2)
                throws IOException, InterruptedException {
            String uname = arg0.getUname();
            StringBuilder stringBuilder = new StringBuilder();
            for (User user : arg1) {
                stringBuilder.append(user.getUname() + ": " + user.getFriedsCount());
                stringBuilder.append(", ");
            }
            arg2.write(new Text(uname), new Text(stringBuilder.toString()));
        }
    }

}

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