HIVE: 自定义TextInputFormat (旧版MapReduceAPI ok, 新版MapReduceAPI实现有BUG？)

我们的输入文件 hello0, 内容如下:

xiaowang 28 shanghai@_@zhangsan 38 beijing@_@someone 100 unknown

逻辑上有3条记录, 它们以@_@分隔. 我们将分别用旧版MapReduce API 和新版MapReduce API实现自定义TextInputFormat，然后在hive配置使用， 加载数据.

 

首先用旧版API

1, 自定义Format6继承自TextInputFormat

package MyTestPackage;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;    
import org.apache.hadoop.io.Text;    
import org.apache.hadoop.mapred.FileSplit;    
import org.apache.hadoop.mapred.InputSplit;    
import org.apache.hadoop.mapred.JobConf;    
import org.apache.hadoop.mapred.JobConfigurable;    
import org.apache.hadoop.mapred.LineRecordReader;
import org.apache.hadoop.mapred.RecordReader;    
import org.apache.hadoop.mapred.Reporter;    
import org.apache.hadoop.mapred.TaskAttemptContext;
import org.apache.hadoop.mapred.TextInputFormat;  


public class Format6 extends TextInputFormat {

    @Override
    public RecordReader getRecordReader (InputSplit split, JobConf job, Reporter reporter)  throws IOException {
        byte[] recordDelimiterBytes = "@_@".getBytes();
        return new LineRecordReader(job, (FileSplit)split, recordDelimiterBytes);
    }
    

}

 

2.导出为MyInputFormat.jar, 放到 hive/lib中

3.在HIVE DDL中配置使用

create table hive_again2(name varchar(50), age int, city varchar(30))
stored as INPUTFORMAT 'MyTestPackage.Format6' OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat';

成功load数据-

 

新API

1, 自定义Format5继承自TextInputFormat

package MyTestPackage;

import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.LineRecordReader;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;


public class Format5 extends TextInputFormat {

    @Override
    public RecordReader createRecordReader (InputSplit split, TaskAttemptContext tac) {
        byte[] recordDelimiterBytes = "@_@".getBytes();
        return new LineRecordReader(recordDelimiterBytes);
    }
    

}

 

2.导出为MyInputFormat.jar, 放到 hive/lib中

3.在HIVE DDL中配置使用

create table hive_again1(name varchar(50), age int, city varchar(30))
stored as INPUTFORMAT 'MyTestPackage.Format5' OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat';

出错了!

把Format5放到MapReduce中debug一切正常(http://www.cnblogs.com/silva/p/4490532.html), 为什么给hive用就不行了呢? 没明白.. 有知道的同学请指点.谢了!