/*******************************************************************************
* Copyright (c) 2000, 2008 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.jdt.internal.core;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.eclipse.jdt.core.IAnnotation;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaElementDelta;
import org.eclipse.jdt.core.IParent;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.core.util.Util;
/**
* A java element delta builder creates a java element delta on a java element between the version
* of the java element at the time the comparator was created and the current version of the java
* element.
*
* It performs this operation by locally caching the contents of the java element when it is
* created. When the method createDeltas() is called, it creates a delta over the cached contents
* and the new contents.
*/
public class JavaElementDeltaBuilder {
/**
* The java element handle
*/
IJavaElement javaElement;
/**
* The maximum depth in the java element children we should look into
*/
int maxDepth= Integer.MAX_VALUE;
/**
* The old handle to info relationships
*/
Map infos;
Map annotationInfos;
/**
* The old position info
*/
Map oldPositions;
/**
* The new position info
*/
Map newPositions;
/**
* Change delta
*/
public JavaElementDelta delta= null;
/**
* List of added elements
*/
HashSet added;
/**
* List of removed elements
*/
HashSet removed;
/**
* Doubly linked list item
*/
static class ListItem {
public IJavaElement previous;
public IJavaElement next;
public ListItem(IJavaElement previous, IJavaElement next) {
this.previous= previous;
this.next= next;
}
}
/**
* Creates a java element comparator on a java element looking as deep as necessary.
*/
public JavaElementDeltaBuilder(IJavaElement javaElement) {
this.javaElement= javaElement;
initialize();
recordElementInfo(
javaElement,
(JavaModel)this.javaElement.getJavaModel(),
0);
}
/**
* Creates a java element comparator on a java element looking only 'maxDepth' levels deep.
*/
public JavaElementDeltaBuilder(IJavaElement javaElement, int maxDepth) {
this.javaElement= javaElement;
this.maxDepth= maxDepth;
initialize();
recordElementInfo(
javaElement,
(JavaModel)this.javaElement.getJavaModel(),
0);
}
/**
* Repairs the positioning information after an element has been added
*/
private void added(IJavaElement element) {
this.added.add(element);
ListItem current= getNewPosition(element);
ListItem previous= null, next= null;
if (current.previous != null)
previous= getNewPosition(current.previous);
if (current.next != null)
next= getNewPosition(current.next);
if (previous != null)
previous.next= current.next;
if (next != null)
next.previous= current.previous;
}
/**
* Builds the java element deltas between the old content of the compilation unit and its new
* content.
*/
public void buildDeltas() {
this.delta= new JavaElementDelta(this.javaElement);
// if building a delta on a compilation unit or below,
// it's a fine grained delta
if (this.javaElement.getElementType() >= IJavaElement.COMPILATION_UNIT) {
this.delta.fineGrained();
}
recordNewPositions(this.javaElement, 0);
findAdditions(this.javaElement, 0);
findDeletions();
findChangesInPositioning(this.javaElement, 0);
trimDelta(this.delta);
if (this.delta.getAffectedChildren().length == 0) {
// this is a fine grained but not children affected -> mark as content changed
this.delta.contentChanged();
}
}
private boolean equals(char[][][] first, char[][][] second) {
if (first == second)
return true;
if (first == null || second == null)
return false;
if (first.length != second.length)
return false;
for (int i= first.length; --i >= 0;)
if (!CharOperation.equals(first[i], second[i]))
return false;
return true;
}
/**
* Finds elements which have been added or changed.
*/
private void findAdditions(IJavaElement newElement, int depth) {
JavaElementInfo oldInfo= getElementInfo(newElement);
if (oldInfo == null && depth < this.maxDepth) {
this.delta.added(newElement);
added(newElement);
} else {
removeElementInfo(newElement);
}
if (depth >= this.maxDepth) {
// mark element as changed
this.delta.changed(newElement, IJavaElementDelta.F_CONTENT);
return;
}
JavaElementInfo newInfo= null;
try {
newInfo= (JavaElementInfo)((JavaElement)newElement).getElementInfo();
} catch (JavaModelException npe) {
return;
}
findContentChange(oldInfo, newInfo, newElement);
if (oldInfo != null && newElement instanceof IParent) {
IJavaElement[] children= newInfo.getChildren();
if (children != null) {
int length= children.length;
for (int i= 0; i < length; i++) {
findAdditions(children[i], depth + 1);
}
}
}
}
/**
* Looks for changed positioning of elements.
*/
private void findChangesInPositioning(IJavaElement element, int depth) {
if (depth >= this.maxDepth || this.added.contains(element) || this.removed.contains(element))
return;
if (!isPositionedCorrectly(element)) {
this.delta.changed(element, IJavaElementDelta.F_REORDER);
}
if (element instanceof IParent) {
JavaElementInfo info= null;
try {
info= (JavaElementInfo)((JavaElement)element).getElementInfo();
} catch (JavaModelException npe) {
return;
}
IJavaElement[] children= info.getChildren();
if (children != null) {
int length= children.length;
for (int i= 0; i < length; i++) {
findChangesInPositioning(children[i], depth + 1);
}
}
}
}
private void findAnnotationChanges(IAnnotation[] oldAnnotations, IAnnotation[] newAnnotations, IJavaElement parent) {
ArrayList annotationDeltas= null;
for (int i= 0, length= newAnnotations.length; i < length; i++) {
IAnnotation newAnnotation= newAnnotations[i];
Object oldInfo= this.annotationInfos.remove(newAnnotation);
if (oldInfo == null) {
JavaElementDelta annotationDelta= new JavaElementDelta(newAnnotation);
annotationDelta.added();
if (annotationDeltas == null)
annotationDeltas= new ArrayList();
annotationDeltas.add(annotationDelta);
continue;
} else {
AnnotationInfo newInfo= null;
try {
newInfo= (AnnotationInfo)((JavaElement)newAnnotation).getElementInfo();
} catch (JavaModelException npe) {
return;
}
if (!Util.equalArraysOrNull(((AnnotationInfo)oldInfo).members, newInfo.members)) {
JavaElementDelta annotationDelta= new JavaElementDelta(newAnnotation);
annotationDelta.changed(IJavaElementDelta.F_CONTENT);
if (annotationDeltas == null)
annotationDeltas= new ArrayList();
annotationDeltas.add(annotationDelta);
}
}
}
for (int i= 0, length= oldAnnotations.length; i < length; i++) {
IAnnotation oldAnnotation= oldAnnotations[i];
if (this.annotationInfos.remove(oldAnnotation) != null) {
JavaElementDelta annotationDelta= new JavaElementDelta(oldAnnotation);
annotationDelta.removed();
if (annotationDeltas == null)
annotationDeltas= new ArrayList();
annotationDeltas.add(annotationDelta);
}
}
if (annotationDeltas == null)
return;
int size= annotationDeltas.size();
if (size > 0) {
JavaElementDelta parentDelta= this.delta.changed(parent, IJavaElementDelta.F_ANNOTATIONS);
parentDelta.annotationDeltas= (IJavaElementDelta[])annotationDeltas.toArray(new IJavaElementDelta[size]);
}
}
/**
* The elements are equivalent, but might have content changes.
*/
private void findContentChange(JavaElementInfo oldInfo, JavaElementInfo newInfo, IJavaElement newElement) {
if (oldInfo instanceof MemberElementInfo && newInfo instanceof MemberElementInfo) {
if (((MemberElementInfo)oldInfo).getModifiers() != ((MemberElementInfo)newInfo).getModifiers()) {
this.delta.changed(newElement, IJavaElementDelta.F_MODIFIERS);
}
if (oldInfo instanceof AnnotatableInfo && newInfo instanceof AnnotatableInfo) {
findAnnotationChanges(((AnnotatableInfo)oldInfo).annotations, ((AnnotatableInfo)newInfo).annotations, newElement);
}
if (oldInfo instanceof SourceMethodElementInfo && newInfo instanceof SourceMethodElementInfo) {
SourceMethodElementInfo oldSourceMethodInfo= (SourceMethodElementInfo)oldInfo;
SourceMethodElementInfo newSourceMethodInfo= (SourceMethodElementInfo)newInfo;
if (!CharOperation.equals(oldSourceMethodInfo.getReturnTypeName(), newSourceMethodInfo.getReturnTypeName())
|| !CharOperation.equals(oldSourceMethodInfo.getTypeParameterNames(), newSourceMethodInfo.getTypeParameterNames())
|| !equals(oldSourceMethodInfo.getTypeParameterBounds(), newSourceMethodInfo.getTypeParameterBounds())) {
this.delta.changed(newElement, IJavaElementDelta.F_CONTENT);
}
} else if (oldInfo instanceof SourceFieldElementInfo && newInfo instanceof SourceFieldElementInfo) {
if (!CharOperation.equals(
((SourceFieldElementInfo)oldInfo).getTypeName(),
((SourceFieldElementInfo)newInfo).getTypeName())) {
this.delta.changed(newElement, IJavaElementDelta.F_CONTENT);
}
} else if (oldInfo instanceof SourceTypeElementInfo && newInfo instanceof SourceTypeElementInfo) {
SourceTypeElementInfo oldSourceTypeInfo= (SourceTypeElementInfo)oldInfo;
SourceTypeElementInfo newSourceTypeInfo= (SourceTypeElementInfo)newInfo;
if (!CharOperation.equals(oldSourceTypeInfo.getSuperclassName(), newSourceTypeInfo.getSuperclassName())
|| !CharOperation.equals(oldSourceTypeInfo.getInterfaceNames(), newSourceTypeInfo.getInterfaceNames())) {
this.delta.changed(newElement, IJavaElementDelta.F_SUPER_TYPES);
}
if (!CharOperation.equals(oldSourceTypeInfo.getTypeParameterNames(), newSourceTypeInfo.getTypeParameterNames())
|| !equals(oldSourceTypeInfo.getTypeParameterBounds(), newSourceTypeInfo.getTypeParameterBounds())) {
this.delta.changed(newElement, IJavaElementDelta.F_CONTENT);
}
HashMap oldTypeCategories= oldSourceTypeInfo.categories;
HashMap newTypeCategories= newSourceTypeInfo.categories;
if (oldTypeCategories != null) {
// take the union of old and new categories elements (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=125675)
Set elements;
if (newTypeCategories != null) {
elements= new HashSet(oldTypeCategories.keySet());
elements.addAll(newTypeCategories.keySet());
} else
elements= oldTypeCategories.keySet();
Iterator iterator= elements.iterator();
while (iterator.hasNext()) {
IJavaElement element= (IJavaElement)iterator.next();
String[] oldCategories= (String[])oldTypeCategories.get(element);
String[] newCategories= newTypeCategories == null ? null : (String[])newTypeCategories.get(element);
if (!Util.equalArraysOrNull(oldCategories, newCategories)) {
this.delta.changed(element, IJavaElementDelta.F_CATEGORIES);
}
}
} else if (newTypeCategories != null) {
Iterator elements= newTypeCategories.keySet().iterator();
while (elements.hasNext()) {
IJavaElement element= (IJavaElement)elements.next();
this.delta.changed(element, IJavaElementDelta.F_CATEGORIES); // all categories for this element were removed
}
}
}
}
}
/**
* Adds removed deltas for any handles left in the table
*/
private void findDeletions() {
Iterator iter= this.infos.keySet().iterator();
while (iter.hasNext()) {
IJavaElement element= (IJavaElement)iter.next();
this.delta.removed(element);
removed(element);
}
}
private JavaElementInfo getElementInfo(IJavaElement element) {
return (JavaElementInfo)this.infos.get(element);
}
private ListItem getNewPosition(IJavaElement element) {
return (ListItem)this.newPositions.get(element);
}
private ListItem getOldPosition(IJavaElement element) {
return (ListItem)this.oldPositions.get(element);
}
private void initialize() {
this.infos= new HashMap(20);
this.oldPositions= new HashMap(20);
this.newPositions= new HashMap(20);
this.oldPositions.put(this.javaElement, new ListItem(null, null));
this.newPositions.put(this.javaElement, new ListItem(null, null));
this.added= new HashSet(5);
this.removed= new HashSet(5);
}
/**
* Inserts position information for the elements into the new or old positions table
*/
private void insertPositions(IJavaElement[] elements, boolean isNew) {
int length= elements.length;
IJavaElement previous= null, current= null, next= (length > 0) ? elements[0] : null;
for (int i= 0; i < length; i++) {
previous= current;
current= next;
next= (i + 1 < length) ? elements[i + 1] : null;
if (isNew) {
this.newPositions.put(current, new ListItem(previous, next));
} else {
this.oldPositions.put(current, new ListItem(previous, next));
}
}
}
/**
* Returns whether the elements position has not changed.
*/
private boolean isPositionedCorrectly(IJavaElement element) {
ListItem oldListItem= getOldPosition(element);
if (oldListItem == null)
return false;
ListItem newListItem= getNewPosition(element);
if (newListItem == null)
return false;
IJavaElement oldPrevious= oldListItem.previous;
IJavaElement newPrevious= newListItem.previous;
if (oldPrevious == null) {
return newPrevious == null;
} else {
return oldPrevious.equals(newPrevious);
}
}
/**
* Records this elements info, and attempts to record the info for the children.
*/
private void recordElementInfo(IJavaElement element, JavaModel model, int depth) {
if (depth >= this.maxDepth) {
return;
}
JavaElementInfo info= (JavaElementInfo)JavaModelManager.getJavaModelManager().getInfo(element);
if (info == null) // no longer in the java model.
return;
this.infos.put(element, info);
if (element instanceof IParent) {
IJavaElement[] children= info.getChildren();
if (children != null) {
insertPositions(children, false);
for (int i= 0, length= children.length; i < length; i++)
recordElementInfo(children[i], model, depth + 1);
}
}
IAnnotation[] annotations= null;
if (info instanceof AnnotatableInfo)
annotations= ((AnnotatableInfo)info).annotations;
if (annotations != null) {
if (this.annotationInfos == null)
this.annotationInfos= new HashMap();
JavaModelManager manager= JavaModelManager.getJavaModelManager();
for (int i= 0, length= annotations.length; i < length; i++) {
this.annotationInfos.put(annotations[i], manager.getInfo(annotations[i]));
}
}
}
/**
* Fills the newPositions hashtable with the new position information
*/
private void recordNewPositions(IJavaElement newElement, int depth) {
if (depth < this.maxDepth && newElement instanceof IParent) {
JavaElementInfo info= null;
try {
info= (JavaElementInfo)((JavaElement)newElement).getElementInfo();
} catch (JavaModelException npe) {
return;
}
IJavaElement[] children= info.getChildren();
if (children != null) {
insertPositions(children, true);
for (int i= 0, length= children.length; i < length; i++) {
recordNewPositions(children[i], depth + 1);
}
}
}
}
/**
* Repairs the positioning information after an element has been removed
*/
private void removed(IJavaElement element) {
this.removed.add(element);
ListItem current= getOldPosition(element);
ListItem previous= null, next= null;
if (current.previous != null)
previous= getOldPosition(current.previous);
if (current.next != null)
next= getOldPosition(current.next);
if (previous != null)
previous.next= current.next;
if (next != null)
next.previous= current.previous;
}
private void removeElementInfo(IJavaElement element) {
this.infos.remove(element);
}
public String toString() {
StringBuffer buffer= new StringBuffer();
buffer.append("Built delta:\n"); //$NON-NLS-1$
buffer.append(this.delta == null ? "<null>" : this.delta.toString()); //$NON-NLS-1$
return buffer.toString();
}
/**
* Trims deletion deltas to only report the highest level of deletion
*/
private void trimDelta(JavaElementDelta elementDelta) {
if (elementDelta.getKind() == IJavaElementDelta.REMOVED) {
IJavaElementDelta[] children= elementDelta.getAffectedChildren();
for (int i= 0, length= children.length; i < length; i++) {
elementDelta.removeAffectedChild((JavaElementDelta)children[i]);
}
} else {
IJavaElementDelta[] children= elementDelta.getAffectedChildren();
for (int i= 0, length= children.length; i < length; i++) {
trimDelta((JavaElementDelta)children[i]);
}
}
}
}