/*******************************************************************************
* Copyright (c) 2000, 2007 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jface.text.rules;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPositionCategoryException;
import org.eclipse.jface.text.DefaultPositionUpdater;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentPartitioner;
import org.eclipse.jface.text.IDocumentPartitionerExtension;
import org.eclipse.jface.text.IDocumentPartitionerExtension2;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITypedRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextUtilities;
import org.eclipse.jface.text.TypedPosition;
import org.eclipse.jface.text.TypedRegion;
/**
* A standard implementation of a syntax driven document partitioner.
* It uses a rule based scanner to scan the document and to determine
* the document's partitioning. The tokens returned by the rules the
* scanner is configured with are supposed to 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.
*
* @see IRule
* @see RuleBasedScanner
*
* @deprecated use <code>FastPartitioner</code> instead
*/
@Deprecated
public class RuleBasedPartitioner implements IDocumentPartitioner, IDocumentPartitionerExtension, IDocumentPartitionerExtension2 {
/**
* The position category this partitioner uses to store the document's partitioning information
* @deprecated As of 3.0, use <code>getManagingPositionCategories()</code>.
*/
@Deprecated
public final static String CONTENT_TYPES_CATEGORY= "__content_types_category"; //$NON-NLS-1$
/** The partitioner's scanner */
protected RuleBasedScanner fScanner;
/** The legal content types of this partitioner */
protected String[] fLegalContentTypes;
/** The partitioner's document */
protected IDocument fDocument;
/** The document length before a document change occurred */
protected int fPreviousDocumentLength;
/** The position updater used to for the default updating of partitions */
protected DefaultPositionUpdater fPositionUpdater;
/** The offset at which the first changed partition starts */
protected int fStartOffset;
/** The offset at which the last changed partition ends */
protected int fEndOffset;
/**The offset at which a partition has been deleted */
protected int fDeleteOffset;
/**
* The position category for managing partitioning information.
* @since 3.0
*/
private String fPositionCategory;
/**
* Creates a new partitioner that uses the given scanner and may return
* partitions of the given legal content types.
*
* @param scanner the scanner this partitioner is supposed to use
* @param legalContentTypes the legal content types of this partitioner
*/
public RuleBasedPartitioner(RuleBasedScanner scanner, String[] legalContentTypes) {
fScanner= scanner;
fLegalContentTypes= TextUtilities.copy(legalContentTypes);
fPositionCategory= CONTENT_TYPES_CATEGORY + hashCode();
fPositionUpdater= new DefaultPositionUpdater(fPositionCategory);
}
@Override
public String[] getManagingPositionCategories() {
return new String[] { fPositionCategory };
}
/*
* @see IDocumentPartitioner#connect
*/
@Override
public void connect(IDocument document) {
Assert.isNotNull(document);
Assert.isTrue(!document.containsPositionCategory(fPositionCategory));
fDocument= document;
fDocument.addPositionCategory(fPositionCategory);
initialize();
}
/**
* Performs the initial partitioning of the partitioner's document.
*/
protected void initialize() {
fScanner.setRange(fDocument, 0, fDocument.getLength());
try {
IToken token= fScanner.nextToken();
while (!token.isEOF()) {
String contentType= getTokenContentType(token);
if (isSupportedContentType(contentType)) {
TypedPosition p= new TypedPosition(fScanner.getTokenOffset(), fScanner.getTokenLength(), contentType);
fDocument.addPosition(fPositionCategory, p);
}
token= fScanner.nextToken();
}
} catch (BadLocationException x) {
// cannot happen as offsets come from scanner
} catch (BadPositionCategoryException x) {
// cannot happen if document has been connected before
}
}
/*
* @see IDocumentPartitioner#disconnect
*/
@Override
public void disconnect() {
Assert.isTrue(fDocument.containsPositionCategory(fPositionCategory));
try {
fDocument.removePositionCategory(fPositionCategory);
} catch (BadPositionCategoryException x) {
// can not happen because of Assert
}
}
/*
* @see IDocumentPartitioner#documentAboutToBeChanged
*/
@Override
public void documentAboutToBeChanged(DocumentEvent e) {
Assert.isTrue(e.getDocument() == fDocument);
fPreviousDocumentLength= e.getDocument().getLength();
fStartOffset= -1;
fEndOffset= -1;
fDeleteOffset= -1;
}
/*
* @see IDocumentPartitioner#documentChanged
*/
@Override
public boolean documentChanged(DocumentEvent e) {
IRegion region= documentChanged2(e);
return (region != null);
}
/**
* Helper method for tracking the minimal region containing all partition changes.
* If <code>offset</code> is smaller than the remembered offset, <code>offset</code>
* will from now on be remembered. If <code>offset + length</code> is greater than
* the remembered end offset, it will be remembered from now on.
*
* @param offset the offset
* @param length the length
*/
private void rememberRegion(int offset, int length) {
// remember start offset
if (fStartOffset == -1)
fStartOffset= offset;
else if (offset < fStartOffset)
fStartOffset= offset;
// remember end offset
int endOffset= offset + length;
if (fEndOffset == -1)
fEndOffset= endOffset;
else if (endOffset > fEndOffset)
fEndOffset= endOffset;
}
/**
* Remembers the given offset as the deletion offset.
*
* @param offset the offset
*/
private void rememberDeletedOffset(int offset) {
fDeleteOffset= offset;
}
/**
* Creates the minimal region containing all partition changes using the
* remembered offset, end offset, and deletion offset.
* @return the minimal region containing all the partition changes
*/
private IRegion createRegion() {
if (fDeleteOffset == -1) {
if (fStartOffset == -1 || fEndOffset == -1)
return null;
return new Region(fStartOffset, fEndOffset - fStartOffset);
} else if (fStartOffset == -1 || fEndOffset == -1) {
return new Region(fDeleteOffset, 0);
} else {
int offset= Math.min(fDeleteOffset, fStartOffset);
int endOffset= Math.max(fDeleteOffset, fEndOffset);
return new Region(offset, endOffset - offset);
}
}
@Override
public IRegion documentChanged2(DocumentEvent e) {
try {
IDocument d= e.getDocument();
Position[] category= d.getPositions(fPositionCategory);
int first= 0;
int reparseStart= 0;
int originalSize= category.length;
if (originalSize > 0) {
/*
* determine character position at which the scanner starts:
* first position behind the last non-default partition the actual position is not involved with
*/
first= d.computeIndexInCategory(fPositionCategory, e.getOffset());
Position p= null;
do {
--first;
if (first < 0)
break;
p= category[first];
} while (p.overlapsWith(e.getOffset(), e.getLength()) ||
(e.getOffset() == fPreviousDocumentLength &&
(p.getOffset() + p.getLength() == fPreviousDocumentLength)));
fPositionUpdater.update(e);
for (Position element : category) {
p= element;
if (p.isDeleted) {
rememberDeletedOffset(e.getOffset());
break;
}
}
category= d.getPositions(fPositionCategory);
if (first >= 0) {
p= category[first];
reparseStart= p.getOffset() + p.getLength();
}
++first;
}
fScanner.setRange(d, reparseStart, d.getLength() - reparseStart);
int lastScannedPosition= reparseStart;
IToken token= fScanner.nextToken();
while (!token.isEOF()) {
String contentType= getTokenContentType(token);
if (!isSupportedContentType(contentType)) {
token= fScanner.nextToken();
continue;
}
int start= fScanner.getTokenOffset();
int length= fScanner.getTokenLength();
lastScannedPosition= start + length - 1;
// remove all affected positions
while (first < category.length) {
TypedPosition p= (TypedPosition) category[first];
if (lastScannedPosition >= p.offset + p.length ||
(p.overlapsWith(start, length) &&
(!d.containsPosition(fPositionCategory, start, length) ||
!contentType.equals(p.getType())))) {
rememberRegion(p.offset, p.length);
d.removePosition(fPositionCategory, p);
++ first;
} else
break;
}
// if position already exists we are done
if (d.containsPosition(fPositionCategory, start, length))
return createRegion();
// insert the new type position
try {
d.addPosition(fPositionCategory, new TypedPosition(start, length, contentType));
rememberRegion(start, length);
} catch (BadPositionCategoryException x) {
} catch (BadLocationException x) {
}
token= fScanner.nextToken();
}
// remove all positions behind lastScannedPosition since there aren't any further types
if (lastScannedPosition != reparseStart) {
// if this condition is not met, nothing has been scanned because of a delete
++ lastScannedPosition;
}
first= d.computeIndexInCategory(fPositionCategory, lastScannedPosition);
TypedPosition p;
while (first < category.length) {
p= (TypedPosition) category[first++];
d.removePosition(fPositionCategory, p);
rememberRegion(p.offset, p.length);
}
} catch (BadPositionCategoryException x) {
// should never happen on connected documents
} catch (BadLocationException x) {
}
return createRegion();
}
/**
* 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.
*
* @param offset the offset for which to search the closest position
* @return the closest position in the partitioner's category
*/
protected TypedPosition findClosestPosition(int offset) {
try {
int index= fDocument.computeIndexInCategory(fPositionCategory, offset);
Position[] category= fDocument.getPositions(fPositionCategory);
if (category.length == 0)
return null;
if (index < category.length) {
if (offset == category[index].offset)
return (TypedPosition) category[index];
}
if (index > 0)
index--;
return (TypedPosition) category[index];
} catch (BadPositionCategoryException x) {
} catch (BadLocationException x) {
}
return null;
}
/*
* @see IDocumentPartitioner#getContentType
*/
@Override
public String getContentType(int offset) {
TypedPosition p= findClosestPosition(offset);
if (p != null && p.includes(offset))
return p.getType();
return IDocument.DEFAULT_CONTENT_TYPE;
}
/*
* @see IDocumentPartitioner#getPartition
*/
@Override
public ITypedRegion getPartition(int offset) {
try {
Position[] category = fDocument.getPositions(fPositionCategory);
if (category == null || category.length == 0)
return new TypedRegion(0, fDocument.getLength(), IDocument.DEFAULT_CONTENT_TYPE);
int index= fDocument.computeIndexInCategory(fPositionCategory, offset);
if (index < category.length) {
TypedPosition next= (TypedPosition) category[index];
if (offset == next.offset)
return new TypedRegion(next.getOffset(), next.getLength(), next.getType());
if (index == 0)
return new TypedRegion(0, next.offset, IDocument.DEFAULT_CONTENT_TYPE);
TypedPosition previous= (TypedPosition) category[index - 1];
if (previous.includes(offset))
return new TypedRegion(previous.getOffset(), previous.getLength(), previous.getType());
int endOffset= previous.getOffset() + previous.getLength();
return new TypedRegion(endOffset, next.getOffset() - endOffset, IDocument.DEFAULT_CONTENT_TYPE);
}
TypedPosition previous= (TypedPosition) category[category.length - 1];
if (previous.includes(offset))
return new TypedRegion(previous.getOffset(), previous.getLength(), previous.getType());
int endOffset= previous.getOffset() + previous.getLength();
return new TypedRegion(endOffset, fDocument.getLength() - endOffset, IDocument.DEFAULT_CONTENT_TYPE);
} catch (BadPositionCategoryException x) {
} catch (BadLocationException x) {
}
return new TypedRegion(0, fDocument.getLength(), IDocument.DEFAULT_CONTENT_TYPE);
}
/*
* @see IDocumentPartitioner#computePartitioning
*/
@Override
public ITypedRegion[] computePartitioning(int offset, int length) {
return computePartitioning(offset, length, false);
}
/*
* @see IDocumentPartitioner#getLegalContentTypes
*/
@Override
public String[] getLegalContentTypes() {
return TextUtilities.copy(fLegalContentTypes);
}
/**
* Returns whether the given type is one of the legal content types.
*
* @param contentType the content type to check
* @return <code>true</code> if the content type is a legal content type
*/
protected boolean isSupportedContentType(String contentType) {
if (contentType != null) {
for (String fLegalContentType : fLegalContentTypes) {
if (fLegalContentType.equals(contentType))
return true;
}
}
return false;
}
/**
* Returns a content type encoded in the given token. If the token's
* data is not <code>null</code> and a string it is assumed that
* it is the encoded content type.
*
* @param token the token whose content type is to be determined
* @return the token's content type
*/
protected String getTokenContentType(IToken token) {
Object data= token.getData();
if (data instanceof String)
return (String) data;
return null;
}
/* zero-length partition support */
@Override
public String getContentType(int offset, boolean preferOpenPartitions) {
return getPartition(offset, preferOpenPartitions).getType();
}
@Override
public ITypedRegion getPartition(int offset, boolean preferOpenPartitions) {
ITypedRegion region= getPartition(offset);
if (preferOpenPartitions) {
if (region.getOffset() == offset && !region.getType().equals(IDocument.DEFAULT_CONTENT_TYPE)) {
if (offset > 0) {
region= getPartition(offset - 1);
if (region.getType().equals(IDocument.DEFAULT_CONTENT_TYPE))
return region;
}
return new TypedRegion(offset, 0, IDocument.DEFAULT_CONTENT_TYPE);
}
}
return region;
}
@Override
public ITypedRegion[] computePartitioning(int offset, int length, boolean includeZeroLengthPartitions) {
List<TypedRegion> list= new ArrayList<>();
try {
int endOffset= offset + length;
Position[] category= fDocument.getPositions(fPositionCategory);
TypedPosition previous= null, current= null;
int start, end, gapOffset;
Position gap= null;
for (Position element : category) {
current= (TypedPosition) element;
gapOffset= (previous != null) ? previous.getOffset() + previous.getLength() : 0;
gap= new Position(gapOffset, current.getOffset() - gapOffset);
if ((includeZeroLengthPartitions || gap.getLength() > 0) && gap.overlapsWith(offset, length)) {
start= Math.max(offset, gapOffset);
end= Math.min(endOffset, gap.getOffset() + gap.getLength());
list.add(new TypedRegion(start, end - start, IDocument.DEFAULT_CONTENT_TYPE));
}
if (current.overlapsWith(offset, length)) {
start= Math.max(offset, current.getOffset());
end= Math.min(endOffset, current.getOffset() + current.getLength());
list.add(new TypedRegion(start, end - start, current.getType()));
}
previous= current;
}
if (previous != null) {
gapOffset= previous.getOffset() + previous.getLength();
gap= new Position(gapOffset, fDocument.getLength() - gapOffset);
if ((includeZeroLengthPartitions || gap.getLength() > 0) && ((includeZeroLengthPartitions && offset + length == gapOffset && gap.length == 0) || gap.overlapsWith(offset, length))) {
start= Math.max(offset, gapOffset);
end= Math.min(endOffset, fDocument.getLength());
list.add(new TypedRegion(start, end - start, IDocument.DEFAULT_CONTENT_TYPE));
}
}
if (list.isEmpty())
list.add(new TypedRegion(offset, length, IDocument.DEFAULT_CONTENT_TYPE));
} catch (BadPositionCategoryException x) {
}
TypedRegion[] result= new TypedRegion[list.size()];
list.toArray(result);
return result;
}
}