mapreudce 通过读取hbase表删除hbase 数据

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package foo.bar.MR;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
import org.apache.hadoop.hbase.mapreduce.TableMapper;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.output.NullOutputFormat;

import foo.bar.validate.Const;

public class DropRowByTimeStampMapReduce  {
	
	   public static Configuration configuration;
	   public static List rowkeyList = new ArrayList();
	   public static List qualifierList = new ArrayList();
	   static {  
	        configuration = HBaseConfiguration.create(); 
	        configuration.set("hbase.zookeeper.quorum",Const.ZOOKEEPER_QUORAM);  
	        configuration.set("hbase.rootdir", Const.HBASE_ROOTDIR);  
	    }  
	    
	static class MyMapper extends TableMapper {
		public void map(ImmutableBytesWritable row, Result r, Context context)
				throws InterruptedException, IOException {
			String tableName = context.getConfiguration().get("tableName");
			HTable htbl = new HTable(configuration, tableName);
			List lists = new ArrayList();
			for (KeyValue kv : r.raw()) {
				Delete dlt = new Delete(kv.getRow());
				dlt.deleteColumn(kv.getFamily(), kv.getQualifier(), kv.getTimestamp());
				lists.add(dlt);
				System.out.println("delete-- gv:"+Bytes.toString(kv.getRow())+",family:"+Bytes.toString(kv.getFamily())+",qualifier:"+Bytes.toString(kv.getQualifier())+",timestamp:"+kv.getTimestamp());
			}
			htbl.delete(lists);
			htbl.flushCommits();
			htbl.close();
		}
	}
		   
	   
	    public static void main(String[] args) throws Exception {  
	    	if(args.length!=2){
	    		return ;
	    	}
	    	String tableName = args[0];
	    	String timeStamp = args[1];
	    	Configuration config = HBaseConfiguration.create();
	    	config.set("tableName", tableName);
	    	Job job = new Job(config, "ExampleRead");
	    	job.setJarByClass(DropRowByTimeStamp.class);     // class that contains mapper
	    		
	    	Scan scan = new Scan();
	    	scan.setCaching(500);        // 1 is the default in Scan, which will be bad for MapReduce jobs
	    	scan.setCacheBlocks(false);  // don't set to true for MR jobs
	        scan.setTimeStamp(new Long(timeStamp));
	    	  
	    	TableMapReduceUtil.initTableMapperJob(
	    	  tableName,        // input HBase table name
	    	  scan,             // Scan instance to control CF and attribute selection
	    	  MyMapper.class,   // mapper
	    	  null,             // mapper output key 
	    	  null,             // mapper output value
	    	  job);
	    	job.setOutputFormatClass(NullOutputFormat.class);   // because we aren't emitting anything from mapper
	    		    
	    	boolean b = job.waitForCompletion(true);
	    	if (!b) {
	    	  throw new IOException("error with job!");
	    	}
	    }  
	    
	   
}