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hbase 从hdfs上读取数据到hbase中

时间:2018-11-18 22:36:09      阅读:165      评论:0      收藏:0      [点我收藏+]

标签:color   mutable   protected   line   row   pac   red   configure   reduce   

 1 <dependencies>
 2     <dependency>
 3         <groupId>org.apache.hbase</groupId>
 4         <artifactId>hbase-client</artifactId>
 5         <version>2.0.2</version>
 6     </dependency>
 7     <dependency>
 8         <groupId>org.apache.hbase</groupId>
 9         <artifactId>hbase-server</artifactId>
10         <version>2.0.2</version>
11     </dependency>
12     <dependency>
13         <groupId>org.apache.hbase</groupId>
14         <artifactId>hbase-mapreduce</artifactId>
15         <version>2.0.2</version>
16     </dependency>
17   </dependencies>

Mappper

 1 package cn.hbase.mapreduce.hdfs;
 2 
 3 import java.io.IOException;
 4 import java.nio.ByteBuffer;
 5 import java.util.ArrayList;
 6 import java.util.HashMap;
 7 import java.util.Iterator;
 8 import java.util.List;
 9 import java.util.Map;
10 import java.util.Map.Entry;
11 import java.util.Set;
12 
13 import org.apache.hadoop.hbase.client.Put;
14 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
15 import org.apache.hadoop.hbase.util.Bytes;
16 import org.apache.hadoop.io.LongWritable;
17 import org.apache.hadoop.io.Text;
18 import org.apache.hadoop.mapreduce.Mapper;
19 
20 /**
21  *
22  * @author Tele 输入key hdfs上的文本的行号 输入value 文本 输出key 行键 输出value 将插入hbase的一行数据,需要行键
23  *
24  */
25 
26 public class ReadFruitFromHdfsMapper extends Mapper<LongWritable, Text, ImmutableBytesWritable, Put> {
27 
28     @Override
29     protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
30         // 读取
31         String line = value.toString();
32 
33         // 切割
34         /**
35          * 1001 apple red 1002 pear yellow 1003 pineapple yellow
36          */
37         String[] fields = line.split("\t");
38 
39         // 每个列族对应多个列
40         Map<String, Object> map = new HashMap<String, Object>();
41 
42         // 封装列族下需要的列
43         List<String> infoCNList = new ArrayList<String>();
44         infoCNList.add("name");// 值对应field[1]
45         infoCNList.add("color");// 值对应field[2]
46         map.put("info", infoCNList);
47 
48         String row = fields[0];
49 
50         // 封装
51         Put put = new Put(Bytes.toBytes(row));
52 
53         // 遍历map,封装每个列族下的列
54         Set<Entry<String, Object>> entrySet = map.entrySet();
55         Iterator<Entry<String, Object>> iterator = entrySet.iterator();
56         while (iterator.hasNext()) {
57             Entry<String, Object> entry = iterator.next();
58             String cf = entry.getKey();
59             List<String> cnList = (List<String>) entry.getValue();
60 
61             // 遍历list
62             for (int i = 0; i < cnList.size(); i++) {
63                 put.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cnList.get(i)), Bytes.toBytes(fields[i + 1]));
64             }
65         }
66 
67         // 行键
68         ImmutableBytesWritable immutableBytesWritable = new ImmutableBytesWritable(Bytes.toBytes(fields[0]));
69 
70         // 写出
71         context.write(immutableBytesWritable, put);
72 
73     }
74 
75 }

Reducer

 1 package cn.hbase.mapreduce.hdfs;
 2 
 3 import java.io.IOException;
 4 
 5 import org.apache.hadoop.hbase.client.Mutation;
 6 import org.apache.hadoop.hbase.client.Put;
 7 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 8 import org.apache.hadoop.hbase.mapreduce.TableReducer;
 9 import org.apache.hadoop.io.NullWritable;
10 import org.apache.hadoop.mapreduce.Reducer;
11 
12 /** 
13  *
14  *@author Tele
15  *
16  *对hbase上的表操作,继承tablereducer即可
17  *
18  */
19 
20 public class WriteFruitReducer extends TableReducer<ImmutableBytesWritable,Put,NullWritable> {
21     
22     @Override
23     protected void reduce(ImmutableBytesWritable key, Iterable<Put> value,Context context) throws IOException, InterruptedException {
24         for (Put put : value) {
25             context.write(NullWritable.get(), put);
26         }
27     }
28     
29 }

Runner

 1 package cn.hbase.mapreduce.hdfs;
 2 
 3 import org.apache.hadoop.conf.Configuration;
 4 import org.apache.hadoop.conf.Configured;
 5 import org.apache.hadoop.fs.Path;
 6 import org.apache.hadoop.hbase.HBaseConfiguration;
 7 import org.apache.hadoop.hbase.client.Put;
 8 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 9 import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
10 import org.apache.hadoop.mapreduce.Job;
11 import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
12 import org.apache.hadoop.util.Tool;
13 import org.apache.hadoop.util.ToolRunner;
14 
15 /**
16  *
17  * @author Tele
18  *
19  */
20 
21 public class FruitRunner extends Configured implements Tool {
22 
23     public int run(String[] args) throws Exception {
24         // 实例化job
25         Job job = Job.getInstance(this.getConf());
26 
27         // 设置jar包路径
28         job.setJarByClass(FruitRunner.class);
29 
30         // 组装mapper
31         job.setMapperClass(ReadFruitFromHdfsMapper.class);
32         job.setMapOutputKeyClass(ImmutableBytesWritable.class);
33         job.setMapOutputValueClass(Put.class);
34 
35         // 设置数据来源
36         FileInputFormat.addInputPath(job, new Path("/input_fruit"));
37 
38         // 组装reducer
39         TableMapReduceUtil.initTableReducerJob("fruit_mr", WriteFruitReducer.class, job);
40 
41         // 设置reduce个数
42         job.setNumReduceTasks(1);
43 
44         // 提交
45 
46         return job.waitForCompletion(true) ? 0 : 1;
47     }
48 
49     public static void main(String[] args) throws Exception {
50         Configuration conf = HBaseConfiguration.create();
51         ToolRunner.run(new FruitRunner(), args);
52 
53     }
54 
55 }

 ps:需要预先创建表

hbase 从hdfs上读取数据到hbase中

标签:color   mutable   protected   line   row   pac   red   configure   reduce   

原文地址:https://www.cnblogs.com/tele-share/p/9979569.html

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