hadoop学习笔记之mapreduce中使用hbase

import java.io.IOException;import java.util.ArrayList;import java.util.List;import java.util.Random;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.fs.FileSystem;import org.apache.hadoop.fs.Path;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.client.HTable;import org.apache.hadoop.hbase.client.Put;import org.apache.hadoop.hbase.util.Bytes;import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Job;import org.apache.hadoop.mapreduce.Mapper;import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;import org.apache.hadoop.metrics.spi.NullContext;import org.apache.hadoop.util.GenericOptionsParser;//mapreduce中使用hbasepublic class InsertDataToHBase {//create 'table1','field1','field2','field3'//create 'table2','field1','field2','field3'//create 'table3','field1','field2','field3'public static class InsertDataToHBaseMapper extendsMapper<Object, Text, NullContext, NullWritable> {public static String table1[] = { "field1", "field2", "field3" };public static String table2[] = { "field1", "field2", "field3" };public static String table3[] = { "field1", "field2", "field3" };public static HTable table = null;protected void setup(Context context) throws IOException,InterruptedException {HBaseConfiguration conf = new HBaseConfiguration();String table_name = context.getConfiguration().get("tabel_name");if (table == null) {table = new HTable(conf, table_name);}}public void map(Object key, Text value, Context context)throws IOException, InterruptedException {String arr_value[] = value.toString().split("\t");String table_name = context.getConfiguration().get("tabel_name");String temp_arr[] = table1;int temp_value_length = 0;if (table_name.trim().equals("table1")) {temp_arr = table1;temp_value_length = 3;} else if (table_name.trim().equals("table2")) {temp_arr = table2;temp_value_length = 3;} else if (table_name.trim().equals("table3")) {temp_arr = table3;temp_value_length = 3;}List<Put> list = new ArrayList<Put>();if (arr_value.length == temp_value_length) {String rowname = System.currentTimeMillis() / 1000 + ""+new Random().nextInt()*100;Put p = new Put(Bytes.toBytes(rowname));for (int i = 0; i < temp_arr.length; i++) {p.add(temp_arr[i].getBytes(), "".getBytes(),arr_value[i].getBytes());}list.add(p);}table.put(list);table.flushCommits();}}public static void main(String[] args) throws Exception {Configuration conf = new Configuration();String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();//data.txt out table3if (otherArgs.length != 3) {System.err.println("Usage: InsertDataToHBase <inpath> <outpath> <tablename>");System.exit(2);}conf.set("tabel_name", otherArgs[2]);Job job = new Job(conf, "InsertDataToHBase");job.setNumReduceTasks(0);job.setJarByClass(InsertDataToHBase.class);job.setMapperClass(InsertDataToHBaseMapper.class);Path inputPath=new Path(otherArgs[0]);Path outputPath=new Path(otherArgs[1]);FileInputFormat.addInputPath(job, inputPath);FileOutputFormat.setOutputPath(job, outputPath);FileSystem hdfs=FileSystem.get(conf);if(hdfs.exists(outputPath)){hdfs.delete(outputPath);}// job.submit();System.exit(job.waitForCompletion(true) ? 0 : 1);}}