ml.shifu.guagua.hadoop.io

Class GuaguaSequenceAsTextRecordReader

java.lang.Object

ml.shifu.guagua.hadoop.io.GuaguaSequenceAsTextRecordReader

All Implemented Interfaces:

GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

public class GuaguaSequenceAsTextRecordReader
extends Object
implements GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

A reader read HDFS sequence file key by key. The sequence key and value types are both BytesWritable.

Copy some code from org.apache.hadoop.mapred.GuaguaSequenceAsTextRecordReader but to support GuaguaRecordReader interface.

If use default constructor, user should also call initialize(GuaguaFileSplit) like in below:

 this.setRecordReader(new GuaguaSequenceAsBinaryRecordReader());
 this.getRecordReader().initialize(fileSplit);
 

or directly use other constructors:

 this.setRecordReader(new GuaguaSequenceAsTextRecordReader(fileSplit));
 

Constructor Summary

Constructors

Constructor and Description
GuaguaSequenceAsTextRecordReader()
GuaguaSequenceAsTextRecordReader(org.apache.hadoop.conf.Configuration conf, GuaguaFileSplit split)
GuaguaSequenceAsTextRecordReader(GuaguaFileSplit split)

Method Summary

Modifier and Type	Method and Description
void	close()
GuaguaWritableAdapter<org.apache.hadoop.io.Text>	getCurrentKey()
GuaguaWritableAdapter<org.apache.hadoop.io.Text>	getCurrentValue()
float	getProgress() Return the progress within the input split
void	initialize(GuaguaFileSplit split)
boolean	nextKeyValue()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GuaguaSequenceAsTextRecordReader

public GuaguaSequenceAsTextRecordReader()

GuaguaSequenceAsTextRecordReader

public GuaguaSequenceAsTextRecordReader(GuaguaFileSplit split)
                                 throws IOException

Throws:

IOException

GuaguaSequenceAsTextRecordReader

public GuaguaSequenceAsTextRecordReader(org.apache.hadoop.conf.Configuration conf,
                                        GuaguaFileSplit split)
                                 throws IOException

Throws:

IOException

Method Detail

getProgress

public float getProgress()
                  throws IOException

Return the progress within the input split

Returns:

0.0 to 1.0 of the input byte range

Throws:

IOException

initialize

public void initialize(GuaguaFileSplit split)
                throws IOException

Specified by:

initialize in interface GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

Throws:

IOException

nextKeyValue

public boolean nextKeyValue()
                     throws IOException

Specified by:

nextKeyValue in interface GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

Throws:

IOException

getCurrentKey

public GuaguaWritableAdapter<org.apache.hadoop.io.Text> getCurrentKey()

Specified by:

getCurrentKey in interface GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

getCurrentValue

public GuaguaWritableAdapter<org.apache.hadoop.io.Text> getCurrentValue()

Specified by:

getCurrentValue in interface GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

close

public void close()
           throws IOException

Specified by:

close in interface GuaguaRecordReader<GuaguaWritableAdapter<org.apache.hadoop.io.Text>,GuaguaWritableAdapter<org.apache.hadoop.io.Text>>

Throws:

IOException