ml.shifu.guagua.hadoop.io
类 GuaguaSequenceRecordReader<KEY extends org.apache.hadoop.io.Writable,VALUE extends org.apache.hadoop.io.Writable>

java.lang.Object
  ml.shifu.guagua.hadoop.io.GuaguaSequenceRecordReader<KEY,VALUE>

所有已实现的接口：

GuaguaRecordReader<GuaguaWritableAdapter<KEY>,GuaguaWritableAdapter<VALUE>>

public class GuaguaSequenceRecordReader<KEY extends org.apache.hadoop.io.Writable,VALUE extends org.apache.hadoop.io.Writable>
extends Object
implements GuaguaRecordReader<GuaguaWritableAdapter<KEY>,GuaguaWritableAdapter<VALUE>>

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

Copy some code from SequenceFileRecordReader but to support GuaguaRecordReader interface.

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

 this.setRecordReader(new SequenceFileRecordReader(Text.class, Text,class));
 this.getRecordReader().initialize(fileSplit);
 

or directly use other constructors:

 this.setRecordReader(new SequenceFileRecordReader(fileSplit, Text.class, Text,class));
 

构造方法摘要

GuaguaSequenceRecordReader(Class<? extends org.apache.hadoop.io.Writable> keyClass, Class<? extends org.apache.hadoop.io.Writable> valueClass)

GuaguaSequenceRecordReader(org.apache.hadoop.conf.Configuration conf, GuaguaFileSplit split, Class<? extends org.apache.hadoop.io.Writable> keyClass, Class<? extends org.apache.hadoop.io.Writable> valueClass)

GuaguaSequenceRecordReader(GuaguaFileSplit split, Class<? extends org.apache.hadoop.io.Writable> keyClass, Class<? extends org.apache.hadoop.io.Writable> valueClass)

方法摘要

void	close()
GuaguaWritableAdapter<KEY>	getCurrentKey()
GuaguaWritableAdapter<VALUE>	getCurrentValue()
float	getProgress() Return the progress within the input split
void	initialize(GuaguaFileSplit split)
boolean	nextKeyValue()

从类 java.lang.Object 继承的方法

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

构造方法详细信息

GuaguaSequenceRecordReader

public GuaguaSequenceRecordReader(Class<? extends org.apache.hadoop.io.Writable> keyClass,
                                  Class<? extends org.apache.hadoop.io.Writable> valueClass)
                           throws IOException

抛出：

IOException

GuaguaSequenceRecordReader

public GuaguaSequenceRecordReader(GuaguaFileSplit split,
                                  Class<? extends org.apache.hadoop.io.Writable> keyClass,
                                  Class<? extends org.apache.hadoop.io.Writable> valueClass)
                           throws IOException

抛出：

IOException

GuaguaSequenceRecordReader

public GuaguaSequenceRecordReader(org.apache.hadoop.conf.Configuration conf,
                                  GuaguaFileSplit split,
                                  Class<? extends org.apache.hadoop.io.Writable> keyClass,
                                  Class<? extends org.apache.hadoop.io.Writable> valueClass)
                           throws IOException

抛出：

IOException

方法详细信息

getProgress

public float getProgress()
                  throws IOException

Return the progress within the input split

返回：

0.0 to 1.0 of the input byte range

抛出：

IOException

initialize

public void initialize(GuaguaFileSplit split)
                throws IOException

指定者：

接口 GuaguaRecordReader<GuaguaWritableAdapter<KEY extends org.apache.hadoop.io.Writable>,GuaguaWritableAdapter<VALUE extends org.apache.hadoop.io.Writable>> 中的 initialize

抛出：

IOException

nextKeyValue

public boolean nextKeyValue()
                     throws IOException

指定者：

接口 GuaguaRecordReader<GuaguaWritableAdapter<KEY extends org.apache.hadoop.io.Writable>,GuaguaWritableAdapter<VALUE extends org.apache.hadoop.io.Writable>> 中的 nextKeyValue

抛出：

IOException

getCurrentKey

public GuaguaWritableAdapter<KEY> getCurrentKey()

指定者：

接口 GuaguaRecordReader<GuaguaWritableAdapter<KEY extends org.apache.hadoop.io.Writable>,GuaguaWritableAdapter<VALUE extends org.apache.hadoop.io.Writable>> 中的 getCurrentKey

getCurrentValue

public GuaguaWritableAdapter<VALUE> getCurrentValue()

指定者：

接口 GuaguaRecordReader<GuaguaWritableAdapter<KEY extends org.apache.hadoop.io.Writable>,GuaguaWritableAdapter<VALUE extends org.apache.hadoop.io.Writable>> 中的 getCurrentValue

close

public void close()
           throws IOException

指定者：

接口 GuaguaRecordReader<GuaguaWritableAdapter<KEY extends org.apache.hadoop.io.Writable>,GuaguaWritableAdapter<VALUE extends org.apache.hadoop.io.Writable>> 中的 close

抛出：

IOException