org.eclipse.jface.text.rules

Class FastPartitioner

java.lang.Object

org.eclipse.jface.text.rules.FastPartitioner

public class FastPartitioner
extends java.lang.Object

A standard implementation of a document partitioner. It uses an IPartitionTokenScanner to scan the document and to determine the document's partitioning. The tokens returned by the scanner must return the partition type as their data. The partitioner remembers the document's partitions in the document itself rather than maintaining its own data structure.

To reduce array creations in IDocument#getPositions(String), the positions get cached. The cache is cleared after updating the positions in documentChanged2(DocumentEvent). Subclasses need to call clearPositionCache() after modifying the partitioner's positions. The cached positions may be accessed through getPositions().

Since:

3.1

See Also:

IPartitionTokenScanner

Field Summary

Fields

Modifier and Type	Field and Description
protected int	fDeleteOffset The offset at which a partition has been deleted
protected IDocument	fDocument The partitioner's document
protected int	fEndOffset The offset at which the last changed partition ends
protected java.lang.String[]	fLegalContentTypes The legal content types of this partitioner
protected DefaultPositionUpdater	fPositionUpdater The position updater used to for the default updating of partitions
protected int	fPreviousDocumentLength The document length before a document change occurred
protected IPartitionTokenScanner	fScanner The partitioner's scanner
protected int	fStartOffset The offset at which the first changed partition starts

Constructor Summary

Constructors

Constructor and Description
FastPartitioner(IPartitionTokenScanner scanner, java.lang.String[] legalContentTypes) Creates a new partitioner that uses the given scanner and may return partitions of the given legal content types.

Method Summary

Modifier and Type	Method and Description
protected void	checkInitialization() Calls initialize() if the receiver is not yet initialized.
protected void	clearPositionCache() Clears the position cache.
ITypedRegion[]	computePartitioning(int offset, int length)
ITypedRegion[]	computePartitioning(int offset, int length, boolean includeZeroLengthPartitions) May be replaced or extended by subclasses.
void	connect(IDocument document)
void	connect(IDocument document, boolean delayInitialization) May be extended by subclasses.
void	disconnect() May be extended by subclasses.
void	documentAboutToBeChanged(DocumentEvent e) May be extended by subclasses.
boolean	documentChanged(DocumentEvent e)
IRegion	documentChanged2(DocumentEvent e) May be extended by subclasses.
protected TypedPosition	findClosestPosition(int offset) Returns the position in the partitoner's position category which is close to the given offset.
protected void	flushRewriteSession() Flushes the active rewrite session.
DocumentRewriteSession	getActiveRewriteSession() May be extended by subclasses.
java.lang.String	getContentType(int offset) May be replaced or extended by subclasses.
java.lang.String	getContentType(int offset, boolean preferOpenPartitions) May be replaced or extended by subclasses.
java.lang.String[]	getLegalContentTypes() May be replaced or extended by subclasses.
java.lang.String[]	getManagingPositionCategories()
ITypedRegion	getPartition(int offset) May be replaced or extended by subclasses.
ITypedRegion	getPartition(int offset, boolean preferOpenPartitions) May be replaced or extended by subclasses.
protected Position[]	getPositions() Returns the partitioners positions.
protected java.lang.String	getTokenContentType(IToken token) Returns a content type encoded in the given token.
protected void	initialize() Performs the initial partitioning of the partitioner's document.
protected boolean	isSupportedContentType(java.lang.String contentType) Returns whether the given type is one of the legal content types.
void	startRewriteSession(DocumentRewriteSession session)
void	stopRewriteSession(DocumentRewriteSession session) May be extended by subclasses.

Methods inherited from class java.lang.Object

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

Field Detail

fScanner

protected final IPartitionTokenScanner fScanner

The partitioner's scanner

fLegalContentTypes

protected final java.lang.String[] fLegalContentTypes

The legal content types of this partitioner

fDocument

protected IDocument fDocument

The partitioner's document

fPreviousDocumentLength

protected int fPreviousDocumentLength

The document length before a document change occurred

fPositionUpdater

protected final DefaultPositionUpdater fPositionUpdater

The position updater used to for the default updating of partitions

fStartOffset

protected int fStartOffset

The offset at which the first changed partition starts

fEndOffset

protected int fEndOffset

The offset at which the last changed partition ends

fDeleteOffset

protected int fDeleteOffset

The offset at which a partition has been deleted

Constructor Detail

FastPartitioner

public FastPartitioner(IPartitionTokenScanner scanner,
                       java.lang.String[] legalContentTypes)

Creates a new partitioner that uses the given scanner and may return partitions of the given legal content types.

Parameters:

scanner - the scanner this partitioner is supposed to use

legalContentTypes - the legal content types of this partitioner

Method Detail

getManagingPositionCategories

public java.lang.String[] getManagingPositionCategories()

connect

public final void connect(IDocument document)

connect

public void connect(IDocument document,
                    boolean delayInitialization)

May be extended by subclasses.

checkInitialization

protected final void checkInitialization()

Calls initialize() if the receiver is not yet initialized.

initialize

protected void initialize()

Performs the initial partitioning of the partitioner's document.

May be extended by subclasses.

disconnect

public void disconnect()

May be extended by subclasses.

documentAboutToBeChanged

public void documentAboutToBeChanged(DocumentEvent e)

May be extended by subclasses.

documentChanged

public final boolean documentChanged(DocumentEvent e)

documentChanged2

public IRegion documentChanged2(DocumentEvent e)

May be extended by subclasses.

findClosestPosition

protected TypedPosition findClosestPosition(int offset)

Returns the position in the partitoner's position category which is close to the given offset. This is, the position has either an offset which is the same as the given offset or an offset which is smaller than the given offset. This method profits from the knowledge that a partitioning is a ordered set of disjoint position.

May be extended or replaced by subclasses.

Parameters:

offset - the offset for which to search the closest position

Returns:

the closest position in the partitioner's category

getContentType

public java.lang.String getContentType(int offset)

May be replaced or extended by subclasses.

getPartition

public ITypedRegion getPartition(int offset)

May be replaced or extended by subclasses.

computePartitioning

public final ITypedRegion[] computePartitioning(int offset,
                                                int length)

getLegalContentTypes

public java.lang.String[] getLegalContentTypes()

May be replaced or extended by subclasses.

isSupportedContentType

protected boolean isSupportedContentType(java.lang.String contentType)

Returns whether the given type is one of the legal content types.

May be extended by subclasses.

Parameters:

contentType - the content type to check

Returns:

true if the content type is a legal content type

getTokenContentType

protected java.lang.String getTokenContentType(IToken token)

Returns a content type encoded in the given token. If the token's data is not null and a string it is assumed that it is the encoded content type.

May be replaced or extended by subclasses.

Parameters:

token - the token whose content type is to be determined

Returns:

the token's content type

getContentType

public java.lang.String getContentType(int offset,
                                       boolean preferOpenPartitions)

May be replaced or extended by subclasses.

getPartition

public ITypedRegion getPartition(int offset,
                                 boolean preferOpenPartitions)

May be replaced or extended by subclasses.

computePartitioning

public ITypedRegion[] computePartitioning(int offset,
                                          int length,
                                          boolean includeZeroLengthPartitions)

May be replaced or extended by subclasses.

startRewriteSession

public void startRewriteSession(DocumentRewriteSession session)
                         throws java.lang.IllegalStateException

Throws:

java.lang.IllegalStateException

stopRewriteSession

public void stopRewriteSession(DocumentRewriteSession session)

May be extended by subclasses.

getActiveRewriteSession

public DocumentRewriteSession getActiveRewriteSession()

May be extended by subclasses.

flushRewriteSession

protected final void flushRewriteSession()

Flushes the active rewrite session.

clearPositionCache

protected final void clearPositionCache()

Clears the position cache. Needs to be called whenever the positions have been updated.

getPositions

protected final Position[] getPositions()
                                 throws BadPositionCategoryException

Returns the partitioners positions.

Returns:

the partitioners positions

Throws:

BadPositionCategoryException - if getting the positions from the document fails