| /******************************************************************************* |
| * Copyright (c) 2001, 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 |
| * Jens Lukowski/Innoopract - initial renaming/restructuring |
| * |
| *******************************************************************************/ |
| package org.eclipse.wst.xml.core.internal.parser.regions; |
| |
| import org.eclipse.wst.sse.core.internal.provisional.events.RegionChangedEvent; |
| import org.eclipse.wst.sse.core.internal.provisional.events.StructuredDocumentEvent; |
| import org.eclipse.wst.sse.core.internal.provisional.text.IStructuredDocumentRegion; |
| import org.eclipse.wst.sse.core.internal.provisional.text.ITextRegion; |
| import org.eclipse.wst.sse.core.internal.util.Debug; |
| import org.eclipse.wst.sse.core.internal.util.Utilities; |
| |
| |
| /** |
| * |
| * This is a utility class to centralize 'region' update. Note: care must be |
| * taken that is is not used for StructuredDocumentRegions, or container |
| * regions, its only for "token regions" |
| * |
| */ |
| public class RegionUpdateRule { |
| |
| static public boolean allLetterOrDigit(String changes) { |
| boolean result = true; |
| for (int i = 0; i < changes.length(); i++) { |
| // TO_DO_FUTURE: check that a Java Letter or Digit is |
| // the same thing as an XML letter or digit |
| if (!(Character.isLetterOrDigit(changes.charAt(i)))) { |
| result = false; |
| break; |
| } |
| } |
| return result; |
| } |
| |
| static public boolean allWhiteSpace(String changes) { |
| boolean result = true; |
| for (int i = 0; i < changes.length(); i++) { |
| if (!Character.isWhitespace(changes.charAt(i))) { |
| result = false; |
| break; |
| } |
| } |
| return result; |
| } |
| |
| static public boolean canHandleAsLetterOrDigit(ITextRegion region, IStructuredDocumentRegion parent, String changes, int requestStart, int lengthToReplace) { |
| if (parent == null) |
| return canHandleAsLetterOrDigit(region, changes, requestStart, lengthToReplace); |
| boolean result = false; |
| // Make sure we are in a non-white space area |
| if ((requestStart <= (parent.getTextEndOffset(region))) && (allLetterOrDigit(changes))) { |
| result = true; |
| } |
| return result; |
| } |
| |
| static public boolean canHandleAsLetterOrDigit(ITextRegion region, String changes, int requestStart, int lengthToReplace) { |
| boolean result = false; |
| // Make sure we are in a non-white space area |
| if ((requestStart <= (region.getTextEnd())) && (allLetterOrDigit(changes))) { |
| result = true; |
| } |
| return result; |
| } |
| |
| static public boolean canHandleAsWhiteSpace(ITextRegion region, IStructuredDocumentRegion parent, String changes, int requestStart, int lengthToReplace) { |
| // we don't explect a null parent, but just in case! |
| // (in which case, we must be dealing with regions that are |
| // structuredDocumentRegions). |
| if (parent == null) |
| return canHandleAsWhiteSpace(region, changes, requestStart, lengthToReplace); |
| boolean result = false; |
| // if we are in the "white space" area of a region, then |
| // we don't want to handle, a reparse is needed. |
| // the white space region is consider anywhere that would |
| // leave whitespace between this character and the text part. |
| // and of course, we can insert whitespace in whitespace region |
| // |
| // if there is no whitespace in this region, no need to look further |
| if (region.getEnd() > region.getTextEnd()) { |
| // no need to add one to end of text, as we used to, since we |
| // change definition of length to equate to offset plus one. |
| // https://bugs.eclipse.org/bugs/show_bug.cgi?id=105866 |
| // watch out for whitespace at end of text |
| if (requestStart >= parent.getTextEndOffset(region)) { |
| // ok, we are in the whitespace region, so we can't handle, |
| // unless |
| // we are just inserting whitespace. |
| if (allWhiteSpace(changes)) { |
| result = true; |
| } else { |
| result = false; |
| } |
| } |
| } |
| return result; |
| } |
| |
| static public boolean canHandleAsWhiteSpace(ITextRegion region, String changes, int requestStart, int lengthToReplace) { |
| boolean result = false; |
| // if we are in the "white space" area of a region, then |
| // we don't want to handle, a reparse is needed. |
| // the white space region is consider anywhere that would |
| // leave whitespace between this character and the text part. |
| // and of course, we can insert whitespace in whitespace region |
| // |
| // if there is no whitespace in this region, no need to look further |
| if (region.getEnd() > region.getTextEnd()) { |
| // no need to add one to end of text, as we used to, since we |
| // change definition of length to equate to offset plus one. |
| // https://bugs.eclipse.org/bugs/show_bug.cgi?id=105866 |
| // watch out for whitespace at end of text |
| if (requestStart >= region.getTextEnd()) { |
| // ok, we are in the whitespace region, so we can't handle, |
| // unless |
| // we are just inserting whitespace. |
| if (allWhiteSpace(changes)) { |
| result = true; |
| } else { |
| result = false; |
| } |
| } |
| } |
| return result; |
| } |
| |
| // need an adjust text length API before this can be used |
| static public StructuredDocumentEvent updateModel(ITextRegion region, Object requester, IStructuredDocumentRegion parent, String changes, int requestStart, int lengthToReplace) { |
| RegionChangedEvent result = null; |
| // if the region is an easy type (e.g. attribute value), |
| // and the requested changes are all |
| // alphanumeric, then make the change here locally. |
| // (This can obviously be made more sophisticated as the need arises, |
| // but should |
| // always follow this pattern.) |
| if (Debug.debugStructuredDocument) { |
| System.out.println("\t\tContextRegion::updateModel"); //$NON-NLS-1$ |
| System.out.println("\t\t\tregion type is " + region.getType()); //$NON-NLS-1$ |
| } |
| boolean canHandle = false; |
| // note: we'll always handle deletes from these |
| // regions ... if its already that region, |
| // deleting something from it won't change its |
| // type. (remember, the calling program needs |
| // to insure we are not called, if not all contained |
| // on one region. |
| if ((changes == null) || (changes.length() == 0)) { |
| // delete case |
| // We can not do the quick delete, if |
| // if all the text in a region is to be deleted. |
| // Or, if the delete starts in the white space region. |
| // In these cases, a reparse is needed. |
| // Minor note, we use textEnd-start since it always |
| // less than or equal to end-start. This might |
| // cause us to miss a few cases we could have handled, |
| // but will prevent us from trying to handle funning cases |
| // involving whitespace. |
| if ((region.getStart() >= region.getTextEnd()) || (Math.abs(lengthToReplace) >= region.getTextEnd() - region.getStart())) { |
| canHandle = false; |
| } else { |
| canHandle = true; |
| } |
| } else { |
| if ((RegionUpdateRule.canHandleAsWhiteSpace(region, parent, changes, requestStart, lengthToReplace)) || RegionUpdateRule.canHandleAsLetterOrDigit(region, parent, changes, requestStart, lengthToReplace)) { |
| canHandle = true; |
| } else { |
| canHandle = false; |
| } |
| } |
| if (canHandle) { |
| // at this point, we still have the old region. We won't create a |
| // new instance, we'll just update the one we have, by changing |
| // its end postion, |
| // The parent flatnode, upon return, has responsibility |
| // for updating sibling regions. |
| // and in turn, the structuredDocument itself has responsibility |
| // for |
| // updating the text store and down stream flatnodes. |
| if (Debug.debugStructuredDocument) { |
| System.out.println("change handled by region"); //$NON-NLS-1$ |
| } |
| int lengthDifference = Utilities.calculateLengthDifference(changes, lengthToReplace); |
| // Note: we adjust both end and text end, because for any change |
| // that is in only the trailing whitespace region, we should not |
| // do a quick change, |
| // so 'canHandle' should have been false for those case. |
| region.adjustLength(lengthDifference); |
| // TO_DO_FUTURE: cache value of canHandleAsWhiteSpace from above |
| // If we are handling as whitespace, there is no need to increase |
| // the text length, only |
| // the total length is changing. |
| if (!RegionUpdateRule.canHandleAsWhiteSpace(region, parent, changes, region.getStart(), lengthToReplace)) { |
| // region.adjustTextLength(lengthDifference); |
| } |
| result = new RegionChangedEvent(parent.getParentDocument(), requester, parent, region, changes, requestStart, lengthToReplace); |
| } |
| return result; |
| } |
| } |