HBase中怎么将已知表移植到另一张表中

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将已经存在某张表，比如 blog，将此表中的数据"移植"到另外一张新表中。

/** * 将HBase中一张表的数据移植到另一张表中。 * */public class HBaseAndMapReduce4 {        public static void main(String[] args) throws Exception {                System.exit(run());        }        public static int run() throws Exception {                Configuration conf = new Configuration();                conf = HBaseConfiguration.create(conf);                conf.set("hbase.zookeeper.quorum", "192.168.226.129");                Job job = Job.getInstance(conf, "findFriend");                job.setJarByClass(HBaseAndMapReduce4.class);                                //实例化scan对象。                Scan scan = new Scan();                scan.addColumn(Bytes.toBytes("article"), Bytes.toBytes("tags"));                scan.addColumn(Bytes.toBytes("author"), Bytes.toBytes("nickname"));                TableMapReduceUtil.initTableMapperJob("blog", scan, FindFriendMapper.class,                                 ImmutableBytesWritable.class, ImmutableBytesWritable.class,job);                                TableMapReduceUtil.initTableReducerJob("friend02", FindFriendReducer.class, job);                                checkTable(conf);                return job.waitForCompletion(true) ? 0 : 1;        }        private static void checkTable(Configuration conf) throws Exception {                Connection con = ConnectionFactory.createConnection(conf);                Admin admin = con.getAdmin();                TableName tn = TableName.valueOf("friend02");                if (!admin.tableExists(tn)){                        HTableDescriptor htd = new HTableDescriptor(tn);                        HColumnDescriptor hcd = new HColumnDescriptor("person");                        htd.addFamily(hcd);                        admin.createTable(htd);                        System.out.println("表不存在，新创建表成功....");                }        }                public static class FindFriendMapper extends TableMapper{                @Override                //key是hbase中的行键                //value是hbase中的所行键的所有数据                protected void map(                                ImmutableBytesWritable key,                                Result value,                                Mapper.Context context)                                throws IOException, InterruptedException {                                                ImmutableBytesWritable v = null;                        String[] kStrs = null;                        List cs = value.listCells();                        for (Cell cell : cs) {                                if ("tags".equals(Bytes.toString(CellUtil.cloneQualifier(cell)))){                                        kStrs = Bytes.toString(CellUtil.cloneValue(cell)).split(",");                                }                                else if ("nickname".equals(Bytes.toString(CellUtil.cloneQualifier(cell)))){                                        v = new ImmutableBytesWritable(CellUtil.cloneValue(cell));                                }                        }                        for (String kStr : kStrs) {                                context.write(new ImmutableBytesWritable(Bytes.toBytes(kStr.toLowerCase())), v);                        }                                        }        }        public static class FindFriendReducer extends                        TableReducer {                @Override                protected void reduce(                                ImmutableBytesWritable key,                                Iterable values,                                Reducer.Context context)                                throws IOException, InterruptedException {                        System.out.println(  "key--->"+key.get() );                        Put put = new Put(key.get());                        StringBuilder vStr = new StringBuilder();                        for (ImmutableBytesWritable value : values) {                                System.out.println( "value-->"+value.get() );                                vStr.append((vStr.length() > 0 ? ",":"") + Bytes.toString(value.get()));                        }                        put.addColumn(Bytes.toBytes("person"), Bytes.toBytes("nickname"),Bytes.toBytes(vStr.toString()));                        context.write(key, put);                }        }}

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