MapReduce编程实现txt文件中的内容导入HBase

一、创建java项目。

写入代码，如下：

package translate1;import java.io.IOException;import org.apache.hadoop.conf.*;import org.apache.hadoop.fs.Path;import  org.apache.hadoop.mapreduce.*;import org.apache.hadoop.io.LongWritable;import  org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.lib.input.*;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.io.*;import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;import org.apache.hadoop.hbase.client.Put;import org.apache.hadoop.hbase.util.Bytes;public class translate1 {        public static Job createSubmittableJob(Configuration conf, String[] args)throws IOException {                       String tableName = args[0];                       Path inputDir = new Path(args[1]);                       @SuppressWarnings("deprecation")                       Job job = new Job (conf, "hac_chapter2_recipe3");                       job.setJarByClass(HourlyImporter.class);                       FileInputFormat.setInputPaths(job, inputDir);                       job.setMapperClass(HourlyImporter.class);                      TableMapReduceUtil.initTableReducerJob(tableName, null, job);                       job.setNumReduceTasks(0);                      TableMapReduceUtil.addDependencyJars(job);                      return job;                               }        public static void main(String[] args)throws Exception {                      Configuration conf = HBaseConfiguration.create();                      Job job = createSubmittableJob(conf, args);                      System.exit (job.waitForCompletion(true) ? 0 : 1);                              }                     }      class HourlyImporter extends Mapper<LongWritable, Text, ImmutableBytesWritable, Put> {         private long ts;         static byte[] family = Bytes.toBytes("n");         @Override         protected void setup(Context context) {          ts = System.currentTimeMillis();           }                     public static String change(String str,int n,boolean j){                               if(str==null||str.length()>=n) return str;                                String s="";                               for(int i=str.length();i<n;i++)                                      s+="0";                              if(j) return s+str;                              else    return str+s;                                }                            @SuppressWarnings("deprecation")                    public void map(LongWritable offset, Text value, Context context)throws IOException {                           try {                                     String line = value.toString();                                     String stationID = line.substring(0, 4);                                     String month = line.substring(5, 7);                                     String day = line.substring(7, 9);                                     String rowkey = stationID + month + day;                                     byte[] bRowKey = Bytes.toBytes(rowkey);                                     ImmutableBytesWritable rowKey =  new ImmutableBytesWritable(bRowKey);                                     Put p = new Put(bRowKey);                                     for (int i = 1; i < 4 ; i++) {                                           String columnI ="v" + change(String.valueOf(i),2,true);                                            int beginIndex = i * 2 + 8;                                           String valueI =line.substring(beginIndex, beginIndex + 2).trim();                                           p.add(family, Bytes.toBytes(columnI),ts, Bytes.toBytes(valueI));                                            }                                    context.write(rowKey, p);                               }catch (InterruptedException e) {                                    e.printStackTrace();                                }                           }               } 

二、上传txt文件到HDFS系统

HDFS中的文件内容为：

三、在HBase终端上创建HBase表格

创建时只需指定要创建表格的表名和列族名

四、配置java项目执行的参数

配置内容如图：

五、执行结果

如图：