org.apache.jackrabbit.rmi.client.iterator

Class ClientIterator

java.lang.Object

org.apache.jackrabbit.rmi.client.ClientObject

org.apache.jackrabbit.rmi.client.iterator.ClientIterator

All Implemented Interfaces:

Iterator, javax.jcr.RangeIterator

Direct Known Subclasses:

ClientAccessControlPolicyIterator, ClientNodeIterator, ClientNodeTypeIterator, ClientPrincipalIterator, ClientPropertyIterator, ClientRowIterator, ClientVersionIterator

public abstract class ClientIterator
extends ClientObject
implements javax.jcr.RangeIterator

A buffering local adapter for the JCR-RMI RemoteIterator interface. This class makes the remote iterator locally available using the JCR RangeIterator interface. The element arrays returned by the remote iterator are buffered locally.

See the subclasses for type-specific versions of this abstract class.

Constructor Summary

Constructors

Constructor and Description
ClientIterator(RemoteIterator remote, LocalAdapterFactory factory) Creates a local adapter for the given remote iterator.

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract Object	getObject(Object remote) Returns a local adapter for the given remote object.
long	getPosition() Returns the current position within the iterator.
long	getSize() Returns the size (the total number of elements) of this iteration.
boolean	hasNext() Checks if there are more elements in this iteration.
Object	next() Returns the next element in this iteration.
void	remove() Not supported.
void	skip(long skipNum) Skips the given number of elements in this iteration.

Methods inherited from class org.apache.jackrabbit.rmi.client.ClientObject

getFactory, getItem, getNode, getNodeTypeArray

Methods inherited from class java.lang.Object

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

Constructor Detail

ClientIterator

public ClientIterator(RemoteIterator remote,
              LocalAdapterFactory factory)

Creates a local adapter for the given remote iterator. The element buffer is initially empty.

Parameters:

remote - remote iterator

factory - local adapter factory

Method Detail

getPosition

public long getPosition()

Returns the current position within the iterator.

Specified by:

getPosition in interface javax.jcr.RangeIterator

Returns:

current position

See Also:

RangeIterator.getPosition()

getSize

public long getSize()
             throws RemoteRuntimeException

Returns the size (the total number of elements) of this iteration. Returns -1 if the size is unknown.

To minimize the number of remote method calls, the size is retrieved when this method is first called and cached for subsequent invocations.

Specified by:

getSize in interface javax.jcr.RangeIterator

Returns:

number of elements in the iteration, or -1

Throws:

RemoteRuntimeException - on RMI errors

See Also:

RangeIterator.getSize()

skip

public void skip(long skipNum)
          throws NoSuchElementException,
                 RemoteRuntimeException

Skips the given number of elements in this iteration.

The elements in the local element buffer are skipped first, and a remote skip method call is made only if more elements are being skipped than remain in the local buffer.

Specified by:

skip in interface javax.jcr.RangeIterator

Parameters:

skipNum - the number of elements to skip

Throws:

NoSuchElementException - if skipped past the last element

RemoteRuntimeException - on RMI errors

See Also:

RangeIterator.skip(long)

hasNext

public boolean hasNext()
                throws RemoteRuntimeException

Checks if there are more elements in this iteration.

Specified by:

hasNext in interface Iterator

Returns:

true if there are more elements, false otherwise

Throws:

RemoteRuntimeException - on RMI errors

getObject

protected abstract Object getObject(Object remote)

Returns a local adapter for the given remote object. This abstract method is used by next() to convert the remote references returned by the remote iterator to local adapters.

Subclasses should implement this method to use the local adapter factory to create local adapters of the specific element type.

Parameters:

remote - remote object

Returns:

local adapter

next

public Object next()
            throws NoSuchElementException,
                   RemoteRuntimeException

Returns the next element in this iteration.

Specified by:

next in interface Iterator

Returns:

next element

Throws:

NoSuchElementException - if there are no more elements

RemoteRuntimeException - on RMI errors

remove

public void remove()
            throws UnsupportedOperationException

Not supported.

Specified by:

remove in interface Iterator

Throws:

UnsupportedOperationException - always thrown