读取myuser这张表当中的数据写入到HBase的另外一张表当中去

第一步：创建myuser2这张表
注意：列族的名字要与myuser表的列族名字相同
hbase(main):010:0> create ‘myuser2’,‘f1’
第二步：创建maven工程，导入jar包

<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>2.6.0-mr1-cdh5.14.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-client</artifactId>
            <version>1.2.0-cdh5.14.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-server</artifactId>
            <version>1.2.0-cdh5.14.0</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.testng</groupId>
            <artifactId>testng</artifactId>
            <version>6.14.3</version>
            <scope>test</scope>
        </dependency>


    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.0</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                    <!--    <verbal>true</verbal>-->
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>2.2</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <filters>
                                <filter>
                                    <artifact>*:*</artifact>
                                    <excludes>
                                        <exclude>META-INF/*.SF</exclude>
                                        <exclude>META-INF/*.DSA</exclude>
                                        <exclude>META-INF/*/RSA</exclude>
                                    </excludes>
                                </filter>
                            </filters>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

第三步：开发MR的程序
1.Mapper

public class HBaseMapper extends TableMapper<Text, Put> {

    @Override
    protected void map(ImmutableBytesWritable key, Result value, Context context) throws IOException, InterruptedException {
        byte[] bytes = key.get();
        String rowKey  = Bytes.toString(bytes);
        Put put = new Put(key.get());

        Cell[] cells = value.rawCells();
        for (Cell cell : cells) {
            if ("f2".equals(Bytes.toString(CellUtil.cloneFamily(cell)))){
                if ("address".equals(Bytes.toString(CellUtil.cloneQualifier(cell)))){
                    put.add(cell);
                }
//                if ("sex".equals(Bytes.toString(CellUtil.cloneQualifier(cell)))){
//                    put.add(cell);
//                }
            }
        }

        if (!put.isEmpty()){
            context.write(new Text(rowKey),put);
        }


    }
}

2.reduce

public class HBaseReducer extends TableReducer<Text, Put, ImmutableBytesWritable>{
    @Override
    protected void reduce(Text key, Iterable<Put> values, Context context) throws IOException, InterruptedException {
        for (Put value : values) {
            context.write(null,value);
        }
    }
}

3、RmHbase

public class RmHbase extends Configured implements Tool {
    //读取myuser这张表当中的数据写入到HBase的另外一张表当中去

    @Override
    public int run(String[] args) throws Exception {
        Job job = Job.getInstance(super.getConf(), "hbaseMr11");
        job.setJarByClass(RmHbase.class);

        Scan scan = new Scan();
        scan.setCaching(500);
        scan.setCacheBlocks(false);

            ////使用TableMapReduceUtil 工具类来初始化我们的mapper
        //TableMapReduceUtil.initTableMapperJob(TableName.valueOf("myuser"),scan,HBaseMapper.class,Text.class,Put.class,job)

        TableMapReduceUtil.initTableMapperJob(TableName.valueOf("myuser"),scan,HBaseMapper.class,Text.class,Put.class,job);

        //使用TableMapReduceUtil 工具类来初始化我们的reducer
        TableMapReduceUtil.initTableReducerJob("myuser3",HBaseReducer.class,job);

        return job.waitForCompletion(false)?0:1;
    }

    public static void main(String[] args)throws Exception {
        Configuration configuration = new Configuration();
        configuration.set("hbase.zookeeper.quorum","hadoop01:2181,hadoop02:2181,hadoop03:2181");
        int run = ToolRunner.run(configuration,new RmHbase(),args);
        System.exit(run);

    }

}

结果：