Package org.apache.hadoop.fs

Class BatchedRemoteIterator<K,E>

java.lang.Object

org.apache.hadoop.fs.BatchedRemoteIterator<K,E>

All Implemented Interfaces:

RemoteIterator<E>

public abstract class BatchedRemoteIterator<K,E>
extends java.lang.Object
implements RemoteIterator<E>

A RemoteIterator that fetches elements in batches.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	BatchedRemoteIterator.BatchedEntries<E>
static class	BatchedRemoteIterator.BatchedListEntries<E>

Constructor Summary

Constructors

Constructor	Description
BatchedRemoteIterator(K prevKey)

Method Summary

Modifier and Type	Method	Description
abstract K	elementToPrevKey(E element)	Return the next list key associated with an element.
boolean	hasNext()	Returns true if the iteration has more elements.
abstract BatchedRemoteIterator.BatchedEntries<E>	makeRequest(K prevKey)	Perform the actual remote request.
E	next()	Returns the next element in the iteration.

Methods inherited from class java.lang.Object

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

Constructor Detail

BatchedRemoteIterator

public BatchedRemoteIterator(K prevKey)

Method Detail

makeRequest

public abstract BatchedRemoteIterator.BatchedEntries<E> makeRequest(K prevKey)
                                                             throws java.io.IOException

Perform the actual remote request.

Parameters:

prevKey - The key to send.

Returns:

A list of replies.

Throws:

java.io.IOException - If an I/O error occurred.

hasNext

public boolean hasNext()
                throws java.io.IOException

Description copied from interface: RemoteIterator

Returns true if the iteration has more elements.

Specified by:

hasNext in interface RemoteIterator<K>

Returns:

true if the iterator has more elements.

Throws:

java.io.IOException - if any IO error occurs

elementToPrevKey

public abstract K elementToPrevKey(E element)

Return the next list key associated with an element.

Parameters:

element - element.

Returns:

K Generics Type.

next

public E next()
       throws java.io.IOException

Description copied from interface: RemoteIterator

Returns the next element in the iteration.

Specified by:

next in interface RemoteIterator<K>

Returns:

the next element in the iteration.

Throws:

java.io.IOException - if any IO error occurs