io.cdap.cdap.api.data.batch

Class SplitReaderBase<KEY,VALUE>

java.lang.Object

io.cdap.cdap.api.data.batch.SplitReader<KEY,VALUE>

io.cdap.cdap.api.data.batch.SplitReaderBase<KEY,VALUE>

Type Parameters:

KEY - The key type.

VALUE - The value type.

Direct Known Subclasses:

IteratorBasedSplitReader

public abstract class SplitReaderBase<KEY,VALUE>
extends SplitReader<KEY,VALUE>

Provides an abstract implementation of SplitReader.

Iterates over split data using the fetchNextKeyValue() method.

Constructor Summary

Constructors

Constructor and Description
SplitReaderBase()

Method Summary

Modifier and Type	Method and Description
void	close() Close the record reader.
protected abstract boolean	fetchNextKeyValue() Fetches the next data item of the split being read.
KEY	getCurrentKey() Get the current key.
VALUE	getCurrentValue() Get the current value.
boolean	nextKeyValue() Read the next key, value pair.
protected void	setCurrentKeyValue(KEY key, VALUE value)

Methods inherited from class io.cdap.cdap.api.data.batch.SplitReader

getProgress, initialize

Methods inherited from class java.lang.Object

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

Constructor Detail

SplitReaderBase

public SplitReaderBase()

Method Detail

fetchNextKeyValue

protected abstract boolean fetchNextKeyValue()

Fetches the next data item of the split being read. If true, use the setCurrentKeyValue(Object, Object) method to set the new current key/value. If false there are no more key/value records to read. See IteratorBasedSplitReader for an implementation of the abstract fetchNextKeyValue() method.

Returns:

false if reached end of the split, true otherwise.

setCurrentKeyValue

protected void setCurrentKeyValue(KEY key,
                                  VALUE value)

nextKeyValue

public boolean nextKeyValue()
                     throws InterruptedException

Description copied from class: SplitReader

Read the next key, value pair.

Specified by:

nextKeyValue in class SplitReader<KEY,VALUE>

Returns:

true if a key/value pair was read.

Throws:

InterruptedException

getCurrentKey

public KEY getCurrentKey()
                  throws InterruptedException

Description copied from class: SplitReader

Get the current key.

Specified by:

getCurrentKey in class SplitReader<KEY,VALUE>

Returns:

The current key, or null if there is no current key.

Throws:

InterruptedException

getCurrentValue

public VALUE getCurrentValue()
                      throws InterruptedException

Description copied from class: SplitReader

Get the current value.

Specified by:

getCurrentValue in class SplitReader<KEY,VALUE>

Returns:

The current value of the object that was read.

Throws:

InterruptedException

close

public void close()

Description copied from class: SplitReader

Close the record reader.

Specified by:

close in class SplitReader<KEY,VALUE>