Package org.apache.ignite.internal.util

Class GridCloseableIteratorAdapter<T>

java.lang.Object

org.apache.ignite.internal.util.lang.GridIteratorAdapter<T>

org.apache.ignite.internal.util.GridCloseableIteratorAdapter<T>

All Implemented Interfaces:

Serializable, AutoCloseable, Iterable<T>, Iterator<T>, GridSerializableIterator<T>, GridCloseableIterator<T>, GridIterator<T>, IgniteSpiCloseableIterator<T>

Direct Known Subclasses:

AbstractScanQueryIterator, AbstractWalRecordsIterator, CacheWeakQueryIteratorsHolder.WeakQueryCloseableIterator, GridSpiCloseableIteratorWrapper, IgniteSingletonIterator

public abstract class GridCloseableIteratorAdapter<T>
extends GridIteratorAdapter<T>
implements GridCloseableIterator<T>

Convenient adapter for closeable iterator.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
GridCloseableIteratorAdapter()

Method Summary

Modifier and Type	Method	Description
protected void	checkClosed()	Throws NoSuchElementException if iterator has been closed.
void	close()	Closes the iterator and frees all the resources held by the iterator.
boolean	hasNextX()	This method is the same as Iterator.hasNext(), but allows for failure with exception.
boolean	isClosed()	Checks if iterator has been closed.
T	nextX()	This method is the same as Iterator.next(), but allows for failure with exception.
protected void	onClose()	Invoked on iterator close.
protected abstract boolean	onHasNext()
protected abstract T	onNext()
protected void	onRemove()	Called on remove from iterator.
void	removeX()	This method is the same as Iterator.remove(), but allows for failure with exception.

Methods inherited from class org.apache.ignite.internal.util.lang.GridIteratorAdapter

hasNext, iterator, next, remove

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

Constructor Detail

GridCloseableIteratorAdapter

public GridCloseableIteratorAdapter()

Method Detail

nextX

public final T nextX()
              throws IgniteCheckedException

This method is the same as Iterator.next(), but allows for failure with exception. Often iterators are used to iterate through values that have not or have partially been received from remote nodes, and need to account for possible network failures, rather than throwing NoSuchElementException runtime exception.s

Specified by:

nextX in interface GridIterator<T>

Returns:

True if iterator contains more elements.

Throws:

IgniteCheckedException - If no more elements can be returned due to some failure, like a network error for example.

See Also:

Iterator.next()

onNext

protected abstract T onNext()
                     throws IgniteCheckedException

Returns:

Next element.

Throws:

IgniteCheckedException - If failed.

NoSuchElementException - If no element found.

hasNextX

public final boolean hasNextX()
                       throws IgniteCheckedException

This method is the same as Iterator.hasNext(), but allows for failure with exception. Often iterators are used to iterate through values that have not or have partially been received from remote nodes, and need to account for possible network failures, rather than just returning false out of Iterator.hasNext() method.

Specified by:

hasNextX in interface GridIterator<T>

Returns:

True if iterator contains more elements.

Throws:

IgniteCheckedException - If no more elements can be returned due to some failure, like a network error for example.

See Also:

Iterator.hasNext()

onHasNext

protected abstract boolean onHasNext()
                              throws IgniteCheckedException

Returns:

True if iterator has next element.

Throws:

IgniteCheckedException - If failed.

removeX

public final void removeX()
                   throws IgniteCheckedException

This method is the same as Iterator.remove(), but allows for failure with exception.

Specified by:

removeX in interface GridIterator<T>

Throws:

IgniteCheckedException - If failed.

onRemove

protected void onRemove()
                 throws IgniteCheckedException

Called on remove from iterator.

Throws:

IgniteCheckedException - If failed.

close

public final void close()
                 throws IgniteCheckedException

Closes the iterator and frees all the resources held by the iterator. Iterator can not be used any more after calling this method.

The method is invoked automatically on objects managed by the try-with-resources statement.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface GridCloseableIterator<T>

Specified by:

close in interface IgniteSpiCloseableIterator<T>

Throws:

IgniteCheckedException - In case of error.

isClosed

public boolean isClosed()

Checks if iterator has been closed.

Specified by:

isClosed in interface GridCloseableIterator<T>

Returns:

True if iterator has been closed.

onClose

protected void onClose()
                throws IgniteCheckedException

Invoked on iterator close.

Throws:

IgniteCheckedException - If closing failed.

checkClosed

protected final void checkClosed()
                          throws NoSuchElementException

Throws NoSuchElementException if iterator has been closed.

Throws:

NoSuchElementException - If iterator has already been closed.