mapreduce读取hbase内容，结果放到hbase中

墨蓝 2022-06-13 06:58 177阅读 0赞

package hadoop;
    
    import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.Cell;
    import org.apache.hadoop.hbase.CellUtil;
    import org.apache.hadoop.hbase.HBaseConfiguration;
    import org.apache.hadoop.hbase.client.Put;
    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.mapreduce.TableReducer;
    import org.apache.hadoop.hbase.util.Bytes;
    import org.apache.hadoop.io.IntWritable;
    import org.apache.hadoop.io.Text;
    import org.apache.hadoop.mapreduce.Job;
    import org.apache.hadoop.mapreduce.Mapper.Context;
    
    import com.sun.jersey.core.util.StringIgnoreCaseKeyComparator;
    
    import hadoop.HbaseMapreduce.HbaseMapper;
    
    public class HbaseToHbase {
    
    	static class HbaseMap extends TableMapper<Text, Text>{
    		@Override
    		protected void map(ImmutableBytesWritable key, Result value,Context context)
    				throws IOException, InterruptedException {
    			for(Cell cell :value.rawCells()){
    				context.write(new Text(Bytes.toString(CellUtil.cloneRow(cell))),new Text(Bytes.toString(CellUtil.cloneQualifier(cell))+","+Bytes.toString(CellUtil.cloneValue(cell))));
    			}
    		}
    		
    	}
    	
    	static class HbaseRed extends TableReducer<Text, Text, ImmutableBytesWritable>{
    		
    		@Override
    		protected void reduce(Text key, Iterable<Text> values,Context context)
    				throws IOException, InterruptedException {
    			
    			for(Text text :values){
    				String line = text.toString();
    				String[] lines = line.split(",");
    				Put put = new Put(key.toString().getBytes());
    				put.add("f".getBytes(), lines[0].getBytes(), lines[1].getBytes());
    				context.write(new ImmutableBytesWritable("result".getBytes()), put);
    			}
    		}
    	}
    	
    	public static void main(String[] args) throws Exception {
    		Configuration conf = HBaseConfiguration.create();
    		conf.set("hbase.zookeeper.quorum", "192.168.10.250");
    		conf.set("hbase.zookeeper.property.clientPort", "2181");
    		Job job = Job.getInstance(conf,"hbasedemo");
    		job.setJarByClass(HbaseToHbase.class);
    		
    		List<Scan> list = new ArrayList<Scan>();
    		Scan scan = new Scan();
    		scan.setCaching(200);
    		scan.setCacheBlocks(false);
    		scan.setStartRow("row1".getBytes());
    		scan.setStopRow("row9".getBytes());
    		scan.setAttribute(Scan.SCAN_ATTRIBUTES_TABLE_NAME, "mapreduce".getBytes());
    		list.add(scan);
    		
    		TableMapReduceUtil.initTableMapperJob(list, HbaseMap.class, Text.class,Text.class, job);
    		
    		TableMapReduceUtil.initTableReducerJob("result", HbaseRed.class, job);
    	
    		job.waitForCompletion(true);
    		return;
    	}
    }