org.modeshape.graph.request
Class ReadNextBlockOfChildrenRequest

java.lang.Object
  org.modeshape.graph.request.Request
      org.modeshape.graph.request.CacheableRequest
          org.modeshape.graph.request.ReadNextBlockOfChildrenRequest

All Implemented Interfaces:

Serializable, Cacheable

public class ReadNextBlockOfChildrenRequest
extends CacheableRequest

Instruction to read a block of the children of a node, where the block is dictated by the location of the child preceding the block and the maximum number of children to include in the block. This command is useful when paging through a large number of children, when the previous block of children was already retrieved and the next block is to be read.

See Also:

ReadBlockOfChildrenRequest, Serialized Form

Field Summary

static int

INDEX_NOT_USED

Constructor Summary

ReadNextBlockOfChildrenRequest(Location startingAfter, String workspaceName, int count)
Create a request to read those children of a node that are immediately after a supplied sibling node.

Method Summary

void	addChild(Location child) Add to the list of children that has been read the child with the given path and identification properties.
void	addChild(Path pathToChild, Property idProperty) Add to the list of children that has been read the child with the given path and identification property.
void	addChild(Path pathToChild, Property firstIdProperty, Property... remainingIdProperties) Add to the list of children that has been read the child with the given path and identification properties.
void	addChildren(Iterable<Location> children) Add to the list of children that has been read the supplied children with the given path and identification properties.
void	cancel() Cancel this request.
int	count() Get the maximum number of children that may be returned in the block.
boolean	equals(Object obj)
Location	getActualLocationOfStartingAfterNode() Get the actual location of the starting after sibling.
List<Location>	getChildren() Get the children that were read from the RepositoryConnection after the request was processed.
RequestType	getType() Returns the type of the request
int	hashCode()
String	inWorkspace() Get the name of the workspace in which the parent and children exist.
boolean	isReadOnly() Return whether this request only reads information.
void	setActualLocationOfStartingAfterNode(Location actual) Sets the actual and complete location of the node whose children have been read.
Location	startingAfter() Get the location of the child after which the block begins.
String	toString()

Methods inherited from class org.modeshape.graph.request.CacheableRequest

getCachePolicy, getTimeLoaded, setCachePolicy, setTimeLoaded

Methods inherited from class org.modeshape.graph.request.Request

checkNotFrozen, freeze, getError, hasError, isCancelled, isFrozen, printable, printable, setError, setLatchForFreezing

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

INDEX_NOT_USED

public static final int INDEX_NOT_USED

See Also:

Constant Field Values

Constructor Detail

ReadNextBlockOfChildrenRequest

public ReadNextBlockOfChildrenRequest(Location startingAfter,
                                      String workspaceName,
                                      int count)

Create a request to read those children of a node that are immediately after a supplied sibling node.

Parameters:

startingAfter - the location of the previous sibling that was the last child of the previous block of children read

workspaceName - the name of the workspace containing the node

count - the maximum number of children that should be included in the block

Throws:

IllegalArgumentException - if the workspace name or startingAfter location is null, or if count is less than 1.

Method Detail

isReadOnly

public boolean isReadOnly()

Return whether this request only reads information.

Specified by:

isReadOnly in class Request

Returns:

true if this request reads information, or false if it requests that the repository content be changed in some way

See Also:

Request.isReadOnly()

count

public int count()

Get the maximum number of children that may be returned in the block.

Returns:

the block's maximum count

See Also:

startingAfter()

startingAfter

public Location startingAfter()

Get the location of the child after which the block begins. This form may be easier to use when paging through blocks, as the last children retrieved with the previous block can be supplied with the next read request.

Returns:

the location of the child that is immediately before the start of the block; index at which this block starts; never negative

See Also:

count()

inWorkspace

public String inWorkspace()

Get the name of the workspace in which the parent and children exist.

Returns:

the name of the workspace; never null

getChildren

public List<Location> getChildren()

Get the children that were read from the RepositoryConnection after the request was processed. Each child is represented by a location.

Returns:

the children that were read; never null

addChildren

public void addChildren(Iterable<Location> children)

Add to the list of children that has been read the supplied children with the given path and identification properties. The children are added in order.

Parameters:

children - the locations of the children that were read

Throws:

IllegalArgumentException - if the parameter is null

IllegalStateException - if the request is frozen

See Also:

addChild(Location), addChild(Path, Property), addChild(Path, Property, Property...)

addChild

public void addChild(Location child)

Add to the list of children that has been read the child with the given path and identification properties. The children should be added in order.

Parameters:

child - the location of the child that was read

Throws:

IllegalArgumentException - if the location is null

IllegalStateException - if the request is frozen

See Also:

addChild(Path, Property), addChild(Path, Property, Property...)

addChild

public void addChild(Path pathToChild,
                     Property firstIdProperty,
                     Property... remainingIdProperties)

Add to the list of children that has been read the child with the given path and identification properties. The children should be added in order.

Parameters:

pathToChild - the path of the child that was just read

firstIdProperty - the first identification property of the child that was just read

remainingIdProperties - the remaining identification properties of the child that was just read

Throws:

IllegalArgumentException - if the path or identification properties are null

IllegalStateException - if the request is frozen

See Also:

addChild(Location), addChild(Path, Property)

addChild

public void addChild(Path pathToChild,
                     Property idProperty)

Add to the list of children that has been read the child with the given path and identification property. The children should be added in order.

Parameters:

pathToChild - the path of the child that was just read

idProperty - the identification property of the child that was just read

Throws:

IllegalArgumentException - if the path or identification properties are null

IllegalStateException - if the request is frozen

See Also:

addChild(Location), addChild(Path, Property, Property...)

setActualLocationOfStartingAfterNode

public void setActualLocationOfStartingAfterNode(Location actual)

Sets the actual and complete location of the node whose children have been read. This method must be called when processing the request, and the actual location must have a path.

Parameters:

actual - the actual location of the node being read, or null if the starting after location should be used

Throws:

IllegalArgumentException - if the actual location is null or does not have a path.

IllegalStateException - if the request is frozen

getActualLocationOfStartingAfterNode

public Location getActualLocationOfStartingAfterNode()

Get the actual location of the starting after sibling.

Returns:

the actual location, or null if the actual location was not set

cancel

public void cancel()

Cancel this request. After this method is called, the cancellation flag is set, and any current or future processing of the request may be affected by the cancellation. (Note however, that processors may choose to not respect this request.)

This method is safe to be called by different threads.

Overrides:

cancel in class Request

See Also:

Request.cancel()

hashCode

public int hashCode()

Overrides:

hashCode in class Object

See Also:

Object.hashCode()

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

See Also:

Object.equals(java.lang.Object)

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

getType

public RequestType getType()

Description copied from class: Request

Returns the type of the request

Specified by:

getType in class Request

Returns:

the type of the request