secure.phpeclipse.com Git - phpeclipse.git/blob

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.ui.text.folding;
  12
  13 import java.util.ArrayList;
  14 import java.util.Collection;
  15 import java.util.Collections;
  16 import java.util.Comparator;
  17 import java.util.HashMap;
  18 import java.util.Iterator;
  19 import java.util.LinkedHashMap;
  20 import java.util.LinkedList;
  21 import java.util.List;
  22 import java.util.Map;
  23
  24 import net.sourceforge.phpdt.core.ElementChangedEvent;
  25 import net.sourceforge.phpdt.core.ICompilationUnit;
  26 import net.sourceforge.phpdt.core.IElementChangedListener;
  27 import net.sourceforge.phpdt.core.IJavaElement;
  28 import net.sourceforge.phpdt.core.IJavaElementDelta;
  29 import net.sourceforge.phpdt.core.IMember;
  30 import net.sourceforge.phpdt.core.IParent;
  31 import net.sourceforge.phpdt.core.ISourceRange;
  32 import net.sourceforge.phpdt.core.ISourceReference;
  33 import net.sourceforge.phpdt.core.IType;
  34 import net.sourceforge.phpdt.core.JavaCore;
  35 import net.sourceforge.phpdt.core.JavaModelException;
  36 import net.sourceforge.phpdt.core.ToolFactory;
  37 import net.sourceforge.phpdt.core.compiler.IScanner;
  38 import net.sourceforge.phpdt.core.compiler.ITerminalSymbols;
  39 import net.sourceforge.phpdt.core.compiler.InvalidInputException;
  40 import net.sourceforge.phpdt.internal.compiler.parser.Scanner;
  41 import net.sourceforge.phpdt.internal.ui.text.DocumentCharacterIterator;
  42 import net.sourceforge.phpdt.ui.IWorkingCopyManager;
  43 import net.sourceforge.phpdt.ui.PreferenceConstants;
  44 import net.sourceforge.phpdt.ui.text.folding.IJavaFoldingStructureProvider;
  45 import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  46 import net.sourceforge.phpeclipse.phpeditor.PHPEditor;
  47 import net.sourceforge.phpeclipse.phpeditor.PHPUnitEditor;
  48 import net.sourceforge.phpeclipse.ui.WebUI;
  49
  50 import org.eclipse.jface.preference.IPreferenceStore;
  51 import org.eclipse.jface.text.Assert;
  52 import org.eclipse.jface.text.BadLocationException;
  53 import org.eclipse.jface.text.IDocument;
  54 import org.eclipse.jface.text.IRegion;
  55 import org.eclipse.jface.text.Position;
  56 import org.eclipse.jface.text.Region;
  57 import org.eclipse.jface.text.source.Annotation;
  58 import org.eclipse.jface.text.source.IAnnotationModel;
  59 import org.eclipse.jface.text.source.projection.IProjectionListener;
  60 import org.eclipse.jface.text.source.projection.IProjectionPosition;
  61 import org.eclipse.jface.text.source.projection.ProjectionAnnotation;
  62 import org.eclipse.jface.text.source.projection.ProjectionAnnotationModel;
  63 import org.eclipse.jface.text.source.projection.ProjectionViewer;
  64 import org.eclipse.ui.texteditor.IDocumentProvider;
  65 import org.eclipse.ui.texteditor.ITextEditor;
  66
  67 /**
  68  * Updates the projection model of a class file or compilation unit.
  69  *
  70  * @since 3.0
  71  */
  72 public class DefaultJavaFoldingStructureProvider implements
  73                 IProjectionListener, IJavaFoldingStructureProvider {
  74
  75         private static class JavaProjectionAnnotation extends ProjectionAnnotation {
  76
  77                 private IJavaElement fJavaElement;
  78
  79                 private boolean fIsComment;
  80
  81                 public JavaProjectionAnnotation(IJavaElement element,
  82                                 boolean isCollapsed, boolean isComment) {
  83                         super(isCollapsed);
  84                         fJavaElement = element;
  85                         fIsComment = isComment;
  86                 }
  87
  88                 public IJavaElement getElement() {
  89                         return fJavaElement;
  90                 }
  91
  92                 public void setElement(IJavaElement element) {
  93                         fJavaElement = element;
  94                 }
  95
  96                 public boolean isComment() {
  97                         return fIsComment;
  98                 }
  99
 100                 public void setIsComment(boolean isComment) {
 101                         fIsComment = isComment;
 102                 }
 103
 104                 /*
 105                  * @see java.lang.Object#toString()
 106                  */
 107                 public String toString() {
 108                         return "JavaProjectionAnnotation:\n" + //$NON-NLS-1$
 109                                         "\telement: \t" + fJavaElement.toString() + "\n" + //$NON-NLS-1$ //$NON-NLS-2$
 110                                         "\tcollapsed: \t" + isCollapsed() + "\n" + //$NON-NLS-1$ //$NON-NLS-2$
 111                                         "\tcomment: \t" + fIsComment + "\n"; //$NON-NLS-1$ //$NON-NLS-2$
 112                 }
 113         }
 114
 115         private static final class Tuple {
 116                 JavaProjectionAnnotation annotation;
 117
 118                 Position position;
 119
 120                 Tuple(JavaProjectionAnnotation annotation, Position position) {
 121                         this.annotation = annotation;
 122                         this.position = position;
 123                 }
 124         }
 125
 126         private class ElementChangedListener implements IElementChangedListener {
 127
 128                 /*
 129                  * @see org.eclipse.jdt.core.IElementChangedListener#elementChanged(org.eclipse.jdt.core.ElementChangedEvent)
 130                  */
 131                 public void elementChanged(ElementChangedEvent e) {
 132                         IJavaElementDelta delta = findElement(fInput, e.getDelta());
 133                         if (delta != null)
 134                                 processDelta(delta);
 135                 }
 136
 137                 private IJavaElementDelta findElement(IJavaElement target,
 138                                 IJavaElementDelta delta) {
 139
 140                         if (delta == null || target == null)
 141                                 return null;
 142
 143                         IJavaElement element = delta.getElement();
 144
 145                         if (element.getElementType() > IJavaElement.CLASS_FILE)
 146                                 return null;
 147
 148                         if (target.equals(element))
 149                                 return delta;
 150
 151                         IJavaElementDelta[] children = delta.getAffectedChildren();
 152
 153                         for (int i = 0; i < children.length; i++) {
 154                                 IJavaElementDelta d = findElement(target, children[i]);
 155                                 if (d != null)
 156                                         return d;
 157                         }
 158
 159                         return null;
 160                 }
 161         }
 162
 163         /**
 164          * Projection position that will return two foldable regions: one folding
 165          * away the region from after the '/**' to the beginning of the content, the
 166          * other from after the first content line until after the comment.
 167          *
 168          * @since 3.1
 169          */
 170         private static final class CommentPosition extends Position implements
 171                         IProjectionPosition {
 172                 CommentPosition(int offset, int length) {
 173                         super(offset, length);
 174                 }
 175
 176                 /*
 177                  * @see org.eclipse.jface.text.source.projection.IProjectionPosition#computeFoldingRegions(org.eclipse.jface.text.IDocument)
 178                  */
 179                 public IRegion[] computeProjectionRegions(IDocument document)
 180                                 throws BadLocationException {
 181                         DocumentCharacterIterator sequence = new DocumentCharacterIterator(
 182                                         document, offset, offset + length);
 183                         int prefixEnd = 0;
 184                         int contentStart = findFirstContent(sequence, prefixEnd);
 185
 186                         int firstLine = document.getLineOfOffset(offset + prefixEnd);
 187                         int captionLine = document.getLineOfOffset(offset + contentStart);
 188                         int lastLine = document.getLineOfOffset(offset + length);
 189
 190                         Assert.isTrue(firstLine <= captionLine,
 191                                         "first folded line is greater than the caption line"); //$NON-NLS-1$
 192                         Assert.isTrue(captionLine <= lastLine,
 193                                         "caption line is greater than the last folded line"); //$NON-NLS-1$
 194
 195                         IRegion preRegion;
 196                         if (firstLine < captionLine) {
 197                                 // preRegion= new Region(offset + prefixEnd, contentStart -
 198                                 // prefixEnd);
 199                                 int preOffset = document.getLineOffset(firstLine);
 200                                 IRegion preEndLineInfo = document
 201                                                 .getLineInformation(captionLine);
 202                                 int preEnd = preEndLineInfo.getOffset();
 203                                 preRegion = new Region(preOffset, preEnd - preOffset);
 204                         } else {
 205                                 preRegion = null;
 206                         }
 207
 208                         if (captionLine < lastLine) {
 209                                 int postOffset = document.getLineOffset(captionLine + 1);
 210                                 IRegion postRegion = new Region(postOffset, offset + length
 211                                                 - postOffset);
 212
 213                                 if (preRegion == null)
 214                                         return new IRegion[] { postRegion };
 215
 216                                 return new IRegion[] { preRegion, postRegion };
 217                         }
 218
 219                         if (preRegion != null)
 220                                 return new IRegion[] { preRegion };
 221
 222                         return null;
 223                 }
 224
 225                 /**
 226                  * Finds the offset of the first identifier part within
 227                  * <code>content</code>. Returns 0 if none is found.
 228                  *
 229                  * @param content
 230                  *            the content to search
 231                  * @return the first index of a unicode identifier part, or zero if none
 232                  *         can be found
 233                  */
 234                 private int findFirstContent(final CharSequence content, int prefixEnd) {
 235                         int lenght = content.length();
 236                         for (int i = prefixEnd; i < lenght; i++) {
 237                                 if (Character.isUnicodeIdentifierPart(content.charAt(i)))
 238                                         return i;
 239                         }
 240                         return 0;
 241                 }
 242
 243                 // /**
 244                 // * Finds the offset of the first identifier part within
 245                 // <code>content</code>.
 246                 // * Returns 0 if none is found.
 247                 // *
 248                 // * @param content the content to search
 249                 // * @return the first index of a unicode identifier part, or zero if
 250                 // none
 251                 // can
 252                 // * be found
 253                 // */
 254                 // private int findPrefixEnd(final CharSequence content) {
 255                 // // return the index after the leading '/*' or '/**'
 256                 // int len= content.length();
 257                 // int i= 0;
 258                 // while (i < len && isWhiteSpace(content.charAt(i)))
 259                 // i++;
 260                 // if (len >= i + 2 && content.charAt(i) == '/' && content.charAt(i + 1)
 261                 // ==
 262                 // '*')
 263                 // if (len >= i + 3 && content.charAt(i + 2) == '*')
 264                 // return i + 3;
 265                 // else
 266                 // return i + 2;
 267                 // else
 268                 // return i;
 269                 // }
 270                 //
 271                 // private boolean isWhiteSpace(char c) {
 272                 // return c == ' ' || c == '\t';
 273                 // }
 274
 275                 /*
 276                  * @see org.eclipse.jface.text.source.projection.IProjectionPosition#computeCaptionOffset(org.eclipse.jface.text.IDocument)
 277                  */
 278                 public int computeCaptionOffset(IDocument document) {
 279                         // return 0;
 280                         DocumentCharacterIterator sequence = new DocumentCharacterIterator(
 281                                         document, offset, offset + length);
 282                         return findFirstContent(sequence, 0);
 283                 }
 284         }
 285
 286         /**
 287          * Projection position that will return two foldable regions: one folding
 288          * away the lines before the one containing the simple name of the java
 289          * element, one folding away any lines after the caption.
 290          *
 291          * @since 3.1
 292          */
 293         private static final class JavaElementPosition extends Position implements
 294                         IProjectionPosition {
 295
 296                 private IMember fMember;
 297
 298                 public JavaElementPosition(int offset, int length, IMember member) {
 299                         super(offset, length);
 300                         Assert.isNotNull(member);
 301                         fMember = member;
 302                 }
 303
 304                 public void setMember(IMember member) {
 305                         Assert.isNotNull(member);
 306                         fMember = member;
 307                 }
 308
 309                 /*
 310                  * @see org.eclipse.jface.text.source.projection.IProjectionPosition#computeFoldingRegions(org.eclipse.jface.text.IDocument)
 311                  */
 312                 public IRegion[] computeProjectionRegions(IDocument document)
 313                                 throws BadLocationException {
 314                         int nameStart = offset;
 315                         try {
 316                                 /*
 317                                  * The member's name range may not be correct. However,
 318                                  * reconciling would trigger another element delta which would
 319                                  * lead to reentrant situations. Therefore, we optimistically
 320                                  * assume that the name range is correct, but double check the
 321                                  * received lines below.
 322                                  */
 323                                 ISourceRange nameRange = fMember.getNameRange();
 324                                 if (nameRange != null)
 325                                         nameStart = nameRange.getOffset();
 326
 327                         } catch (JavaModelException e) {
 328                                 // ignore and use default
 329                         }
 330
 331                         int firstLine = document.getLineOfOffset(offset);
 332                         int captionLine = document.getLineOfOffset(nameStart);
 333                         int lastLine = document.getLineOfOffset(offset + length);
 334
 335                         /*
 336                          * see comment above - adjust the caption line to be inside the
 337                          * entire folded region, and rely on later element deltas to correct
 338                          * the name range.
 339                          */
 340                         if (captionLine < firstLine)
 341                                 captionLine = firstLine;
 342                         if (captionLine > lastLine)
 343                                 captionLine = lastLine;
 344
 345                         IRegion preRegion;
 346                         if (firstLine < captionLine) {
 347                                 int preOffset = document.getLineOffset(firstLine);
 348                                 IRegion preEndLineInfo = document
 349                                                 .getLineInformation(captionLine);
 350                                 int preEnd = preEndLineInfo.getOffset();
 351                                 preRegion = new Region(preOffset, preEnd - preOffset);
 352                         } else {
 353                                 preRegion = null;
 354                         }
 355
 356                         if (captionLine < lastLine) {
 357                                 int postOffset = document.getLineOffset(captionLine + 1);
 358                                 IRegion postRegion = new Region(postOffset, offset + length
 359                                                 - postOffset);
 360
 361                                 if (preRegion == null)
 362                                         return new IRegion[] { postRegion };
 363
 364                                 return new IRegion[] { preRegion, postRegion };
 365                         }
 366
 367                         if (preRegion != null)
 368                                 return new IRegion[] { preRegion };
 369
 370                         return null;
 371                 }
 372
 373                 /*
 374                  * @see org.eclipse.jface.text.source.projection.IProjectionPosition#computeCaptionOffset(org.eclipse.jface.text.IDocument)
 375                  */
 376                 public int computeCaptionOffset(IDocument document)
 377                                 throws BadLocationException {
 378                         int nameStart = offset;
 379                         try {
 380                                 // need a reconcile here?
 381                                 ISourceRange nameRange = fMember.getNameRange();
 382                                 if (nameRange != null)
 383                                         nameStart = nameRange.getOffset();
 384                         } catch (JavaModelException e) {
 385                                 // ignore and use default
 386                         }
 387
 388                         return nameStart - offset;
 389                 }
 390
 391         }
 392
 393         private IDocument fCachedDocument;
 394
 395         private ProjectionAnnotationModel fCachedModel;
 396
 397         private ITextEditor fEditor;
 398
 399         private ProjectionViewer fViewer;
 400
 401         private IJavaElement fInput;
 402
 403         private IElementChangedListener fElementListener;
 404
 405         private boolean fAllowCollapsing = false;
 406
 407         private boolean fCollapseJavadoc = false;
 408
 409         // private boolean fCollapseImportContainer = true;
 410
 411         private boolean fCollapseInnerTypes = true;
 412
 413         private boolean fCollapseMethods = false;
 414
 415         private boolean fCollapseHeaderComments = true;
 416
 417         /* caches for header comment extraction. */
 418         private IType fFirstType;
 419
 420         private boolean fHasHeaderComment;
 421
 422         public DefaultJavaFoldingStructureProvider() {
 423         }
 424
 425         public void install(ITextEditor editor, ProjectionViewer viewer) {
 426                 if (editor instanceof PHPEditor) {
 427                         fEditor = editor;
 428                         fViewer = viewer;
 429                         fViewer.addProjectionListener(this);
 430                 }
 431         }
 432
 433         public void uninstall() {
 434                 if (isInstalled()) {
 435                         projectionDisabled();
 436                         fViewer.removeProjectionListener(this);
 437                         fViewer = null;
 438                         fEditor = null;
 439                 }
 440         }
 441
 442         protected boolean isInstalled() {
 443                 return fEditor != null;
 444         }
 445
 446         /*
 447          * @see org.eclipse.jface.text.source.projection.IProjectionListener#projectionEnabled()
 448          */
 449         public void projectionEnabled() {
 450                 // http://home.ott.oti.com/teams/wswb/anon/out/vms/index.html
 451                 // projectionEnabled messages are not always paired with
 452                 // projectionDisabled
 453                 // i.e. multiple enabled messages may be sent out.
 454                 // we have to make sure that we disable first when getting an enable
 455                 // message.
 456                 projectionDisabled();
 457
 458                 if (fEditor instanceof PHPEditor) {
 459                         initialize();
 460                         fElementListener = new ElementChangedListener();
 461                         JavaCore.addElementChangedListener(fElementListener);
 462                 }
 463         }
 464
 465         /*
 466          * @see org.eclipse.jface.text.source.projection.IProjectionListener#projectionDisabled()
 467          */
 468         public void projectionDisabled() {
 469                 fCachedDocument = null;
 470                 if (fElementListener != null) {
 471                         JavaCore.removeElementChangedListener(fElementListener);
 472                         fElementListener = null;
 473                 }
 474         }
 475
 476         public void initialize() {
 477
 478                 if (!isInstalled())
 479                         return;
 480
 481                 initializePreferences();
 482
 483                 try {
 484
 485                         IDocumentProvider provider = fEditor.getDocumentProvider();
 486                         fCachedDocument = provider.getDocument(fEditor.getEditorInput());
 487                         fAllowCollapsing = true;
 488
 489                         fFirstType = null;
 490                         fHasHeaderComment = false;
 491
 492                         if (fEditor instanceof PHPUnitEditor) {
 493                                 IWorkingCopyManager manager = WebUI.getDefault()
 494                                                 .getWorkingCopyManager();
 495                                 fInput = manager.getWorkingCopy(fEditor.getEditorInput());
 496                         }
 497                         // else if (fEditor instanceof ClassFileEditor) {
 498                         // IClassFileEditorInput editorInput= (IClassFileEditorInput)
 499                         // fEditor.getEditorInput();
 500                         // fInput= editorInput.getClassFile();
 501                         // }
 502
 503                         if (fInput != null) {
 504                                 ProjectionAnnotationModel model = (ProjectionAnnotationModel) fEditor
 505                                                 .getAdapter(ProjectionAnnotationModel.class);
 506                                 if (model != null) {
 507                                         fCachedModel = model;
 508                                         if (fInput instanceof ICompilationUnit) {
 509                                                 ICompilationUnit unit = (ICompilationUnit) fInput;
 510                                                 synchronized (unit) {
 511                                                         try {
 512                                                                 // unit.reconcile(ICompilationUnit.NO_AST,
 513                                                                 // false, null, null);
 514                                                                 unit.reconcile();
 515                                                         } catch (JavaModelException x) {
 516                                                         }
 517                                                 }
 518                                         }
 519
 520                                         Map additions = computeAdditions((IParent) fInput);
 521                                         /*
 522                                          * Minimize the events being sent out - as this happens in
 523                                          * the UI thread merge everything into one call.
 524                                          */
 525                                         List removals = new LinkedList();
 526                                         Iterator existing = model.getAnnotationIterator();
 527                                         while (existing.hasNext())
 528                                                 removals.add(existing.next());
 529                                         model.replaceAnnotations((Annotation[]) removals
 530                                                         .toArray(new Annotation[removals.size()]),
 531                                                         additions);
 532                                 }
 533                         }
 534
 535                 } finally {
 536                         fCachedDocument = null;
 537                         fCachedModel = null;
 538                         fAllowCollapsing = false;
 539
 540                         fFirstType = null;
 541                         fHasHeaderComment = false;
 542                 }
 543         }
 544
 545         private void initializePreferences() {
 546                 IPreferenceStore store = WebUI.getDefault()
 547                                 .getPreferenceStore();
 548                 fCollapseInnerTypes = store
 549                                 .getBoolean(PreferenceConstants.EDITOR_FOLDING_INNERTYPES);
 550                 // fCollapseImportContainer =
 551                 // store.getBoolean(PreferenceConstants.EDITOR_FOLDING_IMPORTS);
 552                 fCollapseJavadoc = store
 553                                 .getBoolean(PreferenceConstants.EDITOR_FOLDING_JAVADOC);
 554                 fCollapseMethods = store
 555                                 .getBoolean(PreferenceConstants.EDITOR_FOLDING_METHODS);
 556                 fCollapseHeaderComments = store
 557                                 .getBoolean(PreferenceConstants.EDITOR_FOLDING_HEADERS);
 558         }
 559
 560         private Map computeAdditions(IParent parent) {
 561                 Map map = new LinkedHashMap(); // use a linked map to maintain ordering
 562                                                                                 // of
 563                 // comments
 564                 try {
 565                         computeAdditions(parent.getChildren(), map);
 566                 } catch (JavaModelException x) {
 567                 }
 568                 return map;
 569         }
 570
 571         private void computeAdditions(IJavaElement[] elements, Map map)
 572                         throws JavaModelException {
 573                 for (int i = 0; i < elements.length; i++) {
 574                         IJavaElement element = elements[i];
 575
 576                         computeAdditions(element, map);
 577
 578                         if (element instanceof IParent) {
 579                                 IParent parent = (IParent) element;
 580                                 computeAdditions(parent.getChildren(), map);
 581                         }
 582                 }
 583         }
 584
 585         private void computeAdditions(IJavaElement element, Map map) {
 586
 587                 boolean createProjection = false;
 588
 589                 boolean collapse = false;
 590                 switch (element.getElementType()) {
 591
 592                 // case IJavaElement.IMPORT_CONTAINER:
 593                 // collapse = fAllowCollapsing && fCollapseImportContainer;
 594                 // createProjection = true;
 595                 // break;
 596                 case IJavaElement.TYPE:
 597                         collapse = fAllowCollapsing;
 598                         if (isInnerType((IType) element)) {
 599                                 collapse = collapse && fCollapseInnerTypes;
 600                         } else {
 601                                 collapse = false; // don't allow the most outer type to be
 602                                                                         // folded, may be changed in future versions
 603                         }
 604                         createProjection = true;
 605                         break;
 606                 case IJavaElement.METHOD:
 607                         collapse = fAllowCollapsing && fCollapseMethods;
 608                         createProjection = true;
 609                         break;
 610                 }
 611
 612                 if (createProjection) {
 613                         IRegion[] regions = computeProjectionRanges(element);
 614                         if (regions != null) {
 615                                 // comments
 616                                 for (int i = 0; i < regions.length - 1; i++) {
 617                                         Position position = createProjectionPosition(regions[i],
 618                                                         null);
 619                                         boolean commentCollapse;
 620                                         if (position != null) {
 621                                                 if (i == 0 && (regions.length > 2 || fHasHeaderComment)
 622                                                                 && element == fFirstType) {
 623                                                         commentCollapse = fAllowCollapsing
 624                                                                         && fCollapseHeaderComments;
 625                                                 } else {
 626                                                         commentCollapse = fAllowCollapsing
 627                                                                         && fCollapseJavadoc;
 628                                                 }
 629                                                 map.put(new JavaProjectionAnnotation(element,
 630                                                                 commentCollapse, true), position);
 631                                         }
 632                                 }
 633                                 // code
 634                                 Position position = createProjectionPosition(
 635                                                 regions[regions.length - 1], element);
 636                                 if (position != null)
 637                                         map.put(new JavaProjectionAnnotation(element, collapse,
 638                                                         false), position);
 639                         }
 640                 }
 641         }
 642
 643         private boolean isInnerType(IType type) {
 644
 645                 try {
 646                         return type.isMember();
 647                 } catch (JavaModelException x) {
 648                         IJavaElement parent = type.getParent();
 649                         if (parent != null) {
 650                                 int parentType = parent.getElementType();
 651                                 return (parentType != IJavaElement.COMPILATION_UNIT && parentType != IJavaElement.CLASS_FILE);
 652                         }
 653                 }
 654
 655                 return false;
 656         }
 657
 658         /**
 659          * Computes the projection ranges for a given <code>IJavaElement</code>.
 660          * More than one range may be returned if the element has a leading comment
 661          * which gets folded separately. If there are no foldable regions,
 662          * <code>null</code> is returned.
 663          *
 664          * @param element
 665          *            the java element that can be folded
 666          * @return the regions to be folded, or <code>null</code> if there are
 667          *         none
 668          */
 669         private IRegion[] computeProjectionRanges(IJavaElement element) {
 670
 671                 try {
 672                         if (element instanceof ISourceReference) {
 673                                 ISourceReference reference = (ISourceReference) element;
 674                                 ISourceRange range = reference.getSourceRange();
 675
 676                                 String contents = reference.getSource();
 677                                 if (contents == null)
 678                                         return null;
 679
 680                                 List regions = new ArrayList();
 681                                 // now add all comments first to the regions list
 682                                 if (fFirstType == null && element instanceof IType) {
 683                                         fFirstType = (IType) element;
 684                                         IRegion headerComment = computeHeaderComment(fFirstType);
 685                                         if (headerComment != null) {
 686                                                 regions.add(headerComment);
 687                                                 fHasHeaderComment = true;
 688                                         }
 689                                 }
 690
 691                                 final int shift = range.getOffset();
 692                                 int start = shift;
 693                                 if (element instanceof IType) {
 694                                         Scanner scanner = ToolFactory.createScanner(true, false,
 695                                                         false, false);
 696                                         scanner.setSource(contents.toCharArray());
 697                                         scanner.setPHPMode(true);
 698
 699                                         int token = scanner.getNextToken();
 700                                         while (token != ITerminalSymbols.TokenNameEOF) {
 701
 702                                                 token = scanner.getNextToken();
 703                                                 start = shift + scanner.getCurrentTokenStartPosition();
 704
 705                                                 switch (token) {
 706                                                 case ITerminalSymbols.TokenNameCOMMENT_PHPDOC:
 707                                                 case ITerminalSymbols.TokenNameCOMMENT_BLOCK: {
 708                                                         int end = shift
 709                                                                         + scanner.getCurrentTokenEndPosition() + 1;
 710                                                         regions.add(new Region(start, end - start));
 711                                                 }
 712                                                 case ITerminalSymbols.TokenNameCOMMENT_LINE:
 713                                                         continue;
 714                                                 }
 715                                         }
 716                                 }
 717                                 // at the end add the element region
 718                                 regions.add(new Region(range.getOffset(), range.getLength()));
 719
 720                                 if (regions.size() > 0) {
 721                                         IRegion[] result = new IRegion[regions.size()];
 722                                         regions.toArray(result);
 723                                         return result;
 724                                 }
 725
 726                         }
 727                 } catch (JavaModelException e) {
 728                 } catch (InvalidInputException e) {
 729                 }
 730
 731                 return null;
 732         }
 733
 734         private IRegion computeHeaderComment(IType type) throws JavaModelException {
 735                 if (fCachedDocument == null)
 736                         return null;
 737
 738                 // search at most up to the first type
 739                 ISourceRange range = type.getSourceRange();
 740                 if (range == null)
 741                         return null;
 742                 int start = 0;
 743                 int end = range.getOffset();
 744
 745                 if (fInput instanceof ISourceReference) {
 746                         String content;
 747                         try {
 748                                 content = fCachedDocument.get(start, end - start);
 749                         } catch (BadLocationException e) {
 750                                 return null; // ignore header comment in that case
 751                         }
 752
 753                         /*
 754                          * code adapted from CommentFormattingStrategy: scan the header
 755                          * content up to the first type. Once a comment is found, accumulate
 756                          * any additional comments up to the stop condition. The stop
 757                          * condition is reaching a package declaration, import container, or
 758                          * the end of the input.
 759                          */
 760                         IScanner scanner = ToolFactory.createScanner(true, false, false,
 761                                         false);
 762                         scanner.setSource(content.toCharArray());
 763
 764                         int headerStart = -1;
 765                         int headerEnd = -1;
 766                         try {
 767                                 boolean foundComment = false;
 768                                 int terminal = scanner.getNextToken();
 769                                 while (terminal != ITerminalSymbols.TokenNameEOF
 770                                                 && !(terminal == ITerminalSymbols.TokenNameclass
 771                                                                 || terminal == ITerminalSymbols.TokenNameinterface || foundComment)) {
 772
 773                                         if (terminal == ITerminalSymbols.TokenNameCOMMENT_PHPDOC
 774                                                         || terminal == ITerminalSymbols.TokenNameCOMMENT_BLOCK
 775                                                         || terminal == ITerminalSymbols.TokenNameCOMMENT_LINE) {
 776                                                 if (!foundComment)
 777                                                         headerStart = scanner
 778                                                                         .getCurrentTokenStartPosition();
 779                                                 headerEnd = scanner.getCurrentTokenEndPosition();
 780                                                 foundComment = true;
 781                                         }
 782                                         terminal = scanner.getNextToken();
 783                                 }
 784
 785                         } catch (InvalidInputException ex) {
 786                                 return null;
 787                         }
 788
 789                         if (headerEnd != -1) {
 790                                 return new Region(headerStart, headerEnd - headerStart);
 791                         }
 792                 }
 793                 return null;
 794         }
 795
 796         private Position createProjectionPosition(IRegion region,
 797                         IJavaElement element) {
 798
 799                 if (fCachedDocument == null)
 800                         return null;
 801
 802                 try {
 803
 804                         int start = fCachedDocument.getLineOfOffset(region.getOffset());
 805                         int end = fCachedDocument.getLineOfOffset(region.getOffset()
 806                                         + region.getLength());
 807                         if (start != end) {
 808                                 int offset = fCachedDocument.getLineOffset(start);
 809                                 int endOffset;
 810                                 if (fCachedDocument.getNumberOfLines() > end + 1)
 811                                         endOffset = fCachedDocument.getLineOffset(end + 1);
 812                                 else if (end > start)
 813                                         endOffset = fCachedDocument.getLineOffset(end)
 814                                                         + fCachedDocument.getLineLength(end);
 815                                 else
 816                                         return null;
 817                                 if (element instanceof IMember)
 818                                         return new JavaElementPosition(offset, endOffset - offset,
 819                                                         (IMember) element);
 820                                 else
 821                                         return new CommentPosition(offset, endOffset - offset);
 822                         }
 823
 824                 } catch (BadLocationException x) {
 825                 }
 826
 827                 return null;
 828         }
 829
 830         protected void processDelta(IJavaElementDelta delta) {
 831
 832                 if (!isInstalled())
 833                         return;
 834
 835                 if ((delta.getFlags() & (IJavaElementDelta.F_CONTENT | IJavaElementDelta.F_CHILDREN)) == 0)
 836                         return;
 837
 838                 ProjectionAnnotationModel model = (ProjectionAnnotationModel) fEditor
 839                                 .getAdapter(ProjectionAnnotationModel.class);
 840                 if (model == null)
 841                         return;
 842
 843                 try {
 844
 845                         IDocumentProvider provider = fEditor.getDocumentProvider();
 846                         fCachedDocument = provider.getDocument(fEditor.getEditorInput());
 847                         fCachedModel = model;
 848                         fAllowCollapsing = false;
 849
 850                         fFirstType = null;
 851                         fHasHeaderComment = false;
 852
 853                         Map additions = new HashMap();
 854                         List deletions = new ArrayList();
 855                         List updates = new ArrayList();
 856
 857                         Map updated = computeAdditions((IParent) fInput);
 858                         Map previous = createAnnotationMap(model);
 859
 860                         Iterator e = updated.keySet().iterator();
 861                         while (e.hasNext()) {
 862                                 JavaProjectionAnnotation newAnnotation = (JavaProjectionAnnotation) e
 863                                                 .next();
 864 //+
 865                                 Position newPosition = (Position) updated.get(newAnnotation);
 866                                 additions.put(newAnnotation, newPosition);
 867 //-
 868 //                              IJavaElement element = newAnnotation.getElement();
 869 //                              Position newPosition = (Position) updated.get(newAnnotation);
 870 //
 871 //                              List annotations = (List) previous.get(element);
 872 //                              if (annotations == null) {
 873 //
 874 //                                      additions.put(newAnnotation, newPosition);
 875 //
 876 //                              } else {
 877 //                                      Iterator x = annotations.iterator();
 878 //                                      boolean matched = false;
 879 //                                      while (x.hasNext()) {
 880 //                                              Tuple tuple = (Tuple) x.next();
 881 //                                              JavaProjectionAnnotation existingAnnotation = tuple.annotation;
 882 //                                              Position existingPosition = tuple.position;
 883 //                                              if (newAnnotation.isComment() == existingAnnotation
 884 //                                                              .isComment()) {
 885 //                                                      if (existingPosition != null
 886 //                                                                      && (!newPosition.equals(existingPosition))) {
 887 //                                                              existingPosition.setOffset(newPosition
 888 //                                                                              .getOffset());
 889 //                                                              existingPosition.setLength(newPosition
 890 //                                                                              .getLength());
 891 //                                                              updates.add(existingAnnotation);
 892 //                                                      }
 893 //                                                      matched = true;
 894 //                                                      x.remove();
 895 //                                                      break;
 896 //                                              }
 897 //                                      }
 898 //                                      if (!matched)
 899 //                                              additions.put(newAnnotation, newPosition);
 900 //
 901 //                                      if (annotations.isEmpty())
 902 //                                              previous.remove(element);
 903 //                              }
 904 //-
 905                         }
 906
 907                         e = previous.values().iterator();
 908                         while (e.hasNext()) {
 909                                 List list = (List) e.next();
 910                                 int size = list.size();
 911                                 for (int i = 0; i < size; i++)
 912                                         deletions.add(((Tuple) list.get(i)).annotation);
 913                         }
 914
 915                         match(deletions, additions, updates);
 916
 917                         Annotation[] removals = new Annotation[deletions.size()];
 918                         deletions.toArray(removals);
 919                         Annotation[] changes = new Annotation[updates.size()];
 920                         updates.toArray(changes);
 921                         model.modifyAnnotations(removals, additions, changes);
 922
 923                 } finally {
 924                         fCachedDocument = null;
 925                         fAllowCollapsing = true;
 926                         fCachedModel = null;
 927
 928                         fFirstType = null;
 929                         fHasHeaderComment = false;
 930                 }
 931         }
 932
 933         /**
 934          * Matches deleted annotations to changed or added ones. A deleted
 935          * annotation/position tuple that has a matching addition / change is
 936          * updated and marked as changed. The matching tuple is not added (for
 937          * additions) or marked as deletion instead (for changes). The result is
 938          * that more annotations are changed and fewer get deleted/re-added.
 939          */
 940         private void match(List deletions, Map additions, List changes) {
 941                 if (deletions.isEmpty() || (additions.isEmpty() && changes.isEmpty()))
 942                         return;
 943
 944                 List newDeletions = new ArrayList();
 945                 List newChanges = new ArrayList();
 946
 947                 Iterator deletionIterator = deletions.iterator();
 948                 while (deletionIterator.hasNext()) {
 949                         JavaProjectionAnnotation deleted = (JavaProjectionAnnotation) deletionIterator
 950                                         .next();
 951                         Position deletedPosition = fCachedModel.getPosition(deleted);
 952                         if (deletedPosition == null)
 953                                 continue;
 954
 955                         Tuple deletedTuple = new Tuple(deleted, deletedPosition);
 956
 957                         Tuple match = findMatch(deletedTuple, changes, null);
 958                         boolean addToDeletions = true;
 959                         if (match == null) {
 960                                 match = findMatch(deletedTuple, additions.keySet(), additions);
 961                                 addToDeletions = false;
 962                         }
 963
 964                         if (match != null) {
 965                                 IJavaElement element = match.annotation.getElement();
 966                                 deleted.setElement(element);
 967                                 deletedPosition.setLength(match.position.getLength());
 968                                 if (deletedPosition instanceof JavaElementPosition
 969                                                 && element instanceof IMember) {
 970                                         JavaElementPosition jep = (JavaElementPosition) deletedPosition;
 971                                         jep.setMember((IMember) element);
 972                                 }
 973
 974                                 deletionIterator.remove();
 975                                 newChanges.add(deleted);
 976
 977                                 if (addToDeletions)
 978                                         newDeletions.add(match.annotation);
 979                         }
 980                 }
 981
 982                 deletions.addAll(newDeletions);
 983                 changes.addAll(newChanges);
 984         }
 985
 986         /**
 987          * Finds a match for <code>tuple</code> in a collection of annotations.
 988          * The positions for the <code>JavaProjectionAnnotation</code> instances
 989          * in <code>annotations</code> can be found in the passed
 990          * <code>positionMap</code> or <code>fCachedModel</code> if
 991          * <code>positionMap</code> is <code>null</code>.
 992          * <p>
 993          * A tuple is said to match another if their annotations have the same
 994          * comment flag and their position offsets are equal.
 995          * </p>
 996          * <p>
 997          * If a match is found, the annotation gets removed from
 998          * <code>annotations</code>.
 999          * </p>
1000          *
1001          * @param tuple
1002          *            the tuple for which we want to find a match
1003          * @param annotations
1004          *            collection of <code>JavaProjectionAnnotation</code>
1005          * @param positionMap
1006          *            a <code>Map&lt;Annotation, Position&gt;</code> or
1007          *            <code>null</code>
1008          * @return a matching tuple or <code>null</code> for no match
1009          */
1010         private Tuple findMatch(Tuple tuple, Collection annotations, Map positionMap) {
1011                 Iterator it = annotations.iterator();
1012                 while (it.hasNext()) {
1013                         JavaProjectionAnnotation annotation = (JavaProjectionAnnotation) it
1014                                         .next();
1015                         if (tuple.annotation.isComment() == annotation.isComment()) {
1016                                 Position position = positionMap == null ? fCachedModel
1017                                                 .getPosition(annotation) : (Position) positionMap
1018                                                 .get(annotation);
1019                                 if (position == null)
1020                                         continue;
1021
1022                                 if (tuple.position.getOffset() == position.getOffset()) {
1023                                         it.remove();
1024                                         return new Tuple(annotation, position);
1025                                 }
1026                         }
1027                 }
1028
1029                 return null;
1030         }
1031
1032         private Map createAnnotationMap(IAnnotationModel model) {
1033                 Map map = new HashMap();
1034                 Iterator e = model.getAnnotationIterator();
1035                 while (e.hasNext()) {
1036                         Object annotation = e.next();
1037                         if (annotation instanceof JavaProjectionAnnotation) {
1038                                 JavaProjectionAnnotation java = (JavaProjectionAnnotation) annotation;
1039                                 Position position = model.getPosition(java);
1040                                 Assert.isNotNull(position);
1041                                 List list = (List) map.get(java.getElement());
1042                                 if (list == null) {
1043                                         list = new ArrayList(2);
1044                                         map.put(java.getElement(), list);
1045                                 }
1046                                 list.add(new Tuple(java, position));
1047                         }
1048                 }
1049
1050                 Comparator comparator = new Comparator() {
1051                         public int compare(Object o1, Object o2) {
1052                                 return ((Tuple) o1).position.getOffset()
1053                                                 - ((Tuple) o2).position.getOffset();
1054                         }
1055                 };
1056                 for (Iterator it = map.values().iterator(); it.hasNext();) {
1057                         List list = (List) it.next();
1058                         Collections.sort(list, comparator);
1059                 }
1060                 return map;
1061         }
1062 }