/*******************************************************************************
* Copyright (c) 2000, 2009 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.wst.jsdt.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.wst.jsdt.core.IJavaScriptElement;
import org.eclipse.wst.jsdt.core.IJavaScriptElementDelta;
import org.eclipse.wst.jsdt.core.IParent;
import org.eclipse.wst.jsdt.core.JavaScriptModelException;
import org.eclipse.wst.jsdt.core.compiler.CharOperation;
import org.eclipse.wst.jsdt.internal.core.util.Util;
/**
* A java element delta biulder 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
*/
IJavaScriptElement 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;
/**
* The old position info
*/
Map oldPositions;
/**
* The new position info
*/
Map newPositions;
/**
* Change delta
*/
public JavaElementDelta delta = null;
/**
* List of added elements
*/
ArrayList added;
/**
* List of removed elements
*/
ArrayList removed;
/**
* Doubly linked list item
*/
static class ListItem {
public IJavaScriptElement previous;
public IJavaScriptElement next;
public ListItem(IJavaScriptElement previous, IJavaScriptElement next) {
this.previous = previous;
this.next = next;
}
}
/**
* Creates a java element comparator on a java element
* looking as deep as necessary.
*/
public JavaElementDeltaBuilder(IJavaScriptElement javaElement) {
this.javaElement = javaElement;
this.initialize();
this.recordElementInfo(
javaElement,
(JavaModel)this.javaElement.getJavaScriptModel(),
0);
}
/**
* Creates a java element comparator on a java element
* looking only 'maxDepth' levels deep.
*/
public JavaElementDeltaBuilder(IJavaScriptElement javaElement, int maxDepth) {
this.javaElement = javaElement;
this.maxDepth = maxDepth;
this.initialize();
this.recordElementInfo(
javaElement,
(JavaModel)this.javaElement.getJavaScriptModel(),
0);
}
/**
* Repairs the positioning information
* after an element has been added
*/
private void added(IJavaScriptElement element) {
this.added.add(element);
ListItem current = this.getNewPosition(element);
ListItem previous = null, next = null;
if (current.previous != null)
previous = this.getNewPosition(current.previous);
if (current.next != null)
next = this.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() >= IJavaScriptElement.JAVASCRIPT_UNIT) {
this.delta.fineGrained();
}
this.recordNewPositions(this.javaElement, 0);
this.findAdditions(this.javaElement, 0);
this.findDeletions();
this.findChangesInPositioning(this.javaElement, 0);
this.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(IJavaScriptElement newElement, int depth) {
JavaElementInfo oldInfo = this.getElementInfo(newElement);
if (oldInfo == null && depth < this.maxDepth) {
this.delta.added(newElement);
added(newElement);
} else {
this.removeElementInfo(newElement);
}
if (depth >= this.maxDepth) {
// mark element as changed
this.delta.changed(newElement, IJavaScriptElementDelta.F_CONTENT);
return;
}
JavaElementInfo newInfo = null;
try {
newInfo = (JavaElementInfo)((JavaElement)newElement).getElementInfo();
} catch (JavaScriptModelException npe) {
return;
}
this.findContentChange(oldInfo, newInfo, newElement);
if (oldInfo != null && newElement instanceof IParent) {
IJavaScriptElement[] children = newInfo.getChildren();
if (children != null) {
int length = children.length;
for(int i = 0; i < length; i++) {
this.findAdditions(children[i], depth + 1);
}
}
}
}
/**
* Looks for changed positioning of elements.
*/
private void findChangesInPositioning(IJavaScriptElement element, int depth) {
if (depth >= this.maxDepth || this.added.contains(element) || this.removed.contains(element))
return;
if (!isPositionedCorrectly(element)) {
this.delta.changed(element, IJavaScriptElementDelta.F_REORDER);
}
if (element instanceof IParent) {
JavaElementInfo info = null;
try {
info = (JavaElementInfo)((JavaElement)element).getElementInfo();
} catch (JavaScriptModelException npe) {
return;
}
IJavaScriptElement[] children = info.getChildren();
if (children != null) {
int length = children.length;
for(int i = 0; i < length; i++) {
this.findChangesInPositioning(children[i], depth + 1);
}
}
}
}
/**
* The elements are equivalent, but might have content changes.
*/
private void findContentChange(JavaElementInfo oldInfo, JavaElementInfo newInfo, IJavaScriptElement newElement) {
if (oldInfo instanceof MemberElementInfo && newInfo instanceof MemberElementInfo) {
if (((MemberElementInfo)oldInfo).getModifiers() != ((MemberElementInfo)newInfo).getModifiers()) {
this.delta.changed(newElement, IJavaScriptElementDelta.F_MODIFIERS);
} else if (oldInfo instanceof SourceMethodElementInfo && newInfo instanceof SourceMethodElementInfo) {
SourceMethodElementInfo oldSourceMethodInfo = (SourceMethodElementInfo)oldInfo;
SourceMethodElementInfo newSourceMethodInfo = (SourceMethodElementInfo)newInfo;
if (!CharOperation.equals(oldSourceMethodInfo.getReturnTypeName(), newSourceMethodInfo.getReturnTypeName())) {
this.delta.changed(newElement, IJavaScriptElementDelta.F_CONTENT);
}
} else if (oldInfo instanceof SourceFieldElementInfo && newInfo instanceof SourceFieldElementInfo) {
if (!CharOperation.equals(
((SourceFieldElementInfo)oldInfo).getTypeName(),
((SourceFieldElementInfo)newInfo).getTypeName())) {
this.delta.changed(newElement, IJavaScriptElementDelta.F_CONTENT);
}
}
}
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, IJavaScriptElementDelta.F_SUPER_TYPES);
}
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()) {
IJavaScriptElement element = (IJavaScriptElement) 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, IJavaScriptElementDelta.F_CATEGORIES);
}
}
} else if (newTypeCategories != null) {
Iterator elements = newTypeCategories.keySet().iterator();
while (elements.hasNext()) {
IJavaScriptElement element = (IJavaScriptElement) elements.next();
this.delta.changed(element, IJavaScriptElementDelta.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()) {
IJavaScriptElement element = (IJavaScriptElement)iter.next();
this.delta.removed(element);
this.removed(element);
}
}
private JavaElementInfo getElementInfo(IJavaScriptElement element) {
return (JavaElementInfo)this.infos.get(element);
}
private ListItem getNewPosition(IJavaScriptElement element) {
return (ListItem)this.newPositions.get(element);
}
private ListItem getOldPosition(IJavaScriptElement 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.putOldPosition(this.javaElement, new ListItem(null, null));
this.putNewPosition(this.javaElement, new ListItem(null, null));
this.added = new ArrayList(5);
this.removed = new ArrayList(5);
}
/**
* Inserts position information for the elements into the new or old positions table
*/
private void insertPositions(IJavaScriptElement[] elements, boolean isNew) {
int length = elements.length;
IJavaScriptElement 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.putNewPosition(current, new ListItem(previous, next));
} else {
this.putOldPosition(current, new ListItem(previous, next));
}
}
}
/**
* Returns whether the elements position has not changed.
*/
private boolean isPositionedCorrectly(IJavaScriptElement element) {
ListItem oldListItem = this.getOldPosition(element);
if (oldListItem == null) return false;
ListItem newListItem = this.getNewPosition(element);
if (newListItem == null) return false;
IJavaScriptElement oldPrevious = oldListItem.previous;
IJavaScriptElement newPrevious = newListItem.previous;
if (oldPrevious == null) {
return newPrevious == null;
} else {
return oldPrevious.equals(newPrevious);
}
}
private void putElementInfo(IJavaScriptElement element, JavaElementInfo info) {
this.infos.put(element, info);
}
private void putNewPosition(IJavaScriptElement element, ListItem position) {
this.newPositions.put(element, position);
}
private void putOldPosition(IJavaScriptElement element, ListItem position) {
this.oldPositions.put(element, position);
}
/**
* Records this elements info, and attempts
* to record the info for the children.
*/
private void recordElementInfo(IJavaScriptElement 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.putElementInfo(element, info);
if (element instanceof IParent) {
IJavaScriptElement[] 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);
}
}
}
/**
* Fills the newPositions hashtable with the new position information
*/
private void recordNewPositions(IJavaScriptElement newElement, int depth) {
if (depth < this.maxDepth && newElement instanceof IParent) {
JavaElementInfo info = null;
try {
info = (JavaElementInfo)((JavaElement)newElement).getElementInfo();
} catch (JavaScriptModelException npe) {
return;
}
IJavaScriptElement[] 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(IJavaScriptElement element) {
this.removed.add(element);
ListItem current = this.getOldPosition(element);
ListItem previous = null, next = null;
if (current.previous != null)
previous = this.getOldPosition(current.previous);
if (current.next != null)
next = this.getOldPosition(current.next);
if (previous != null)
previous.next = current.next;
if (next != null)
next.previous = current.previous;
}
private void removeElementInfo(IJavaScriptElement 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() == IJavaScriptElementDelta.REMOVED) {
IJavaScriptElementDelta[] children = elementDelta.getAffectedChildren();
for(int i = 0, length = children.length; i < length; i++) {
elementDelta.removeAffectedChild((JavaElementDelta)children[i]);
}
} else {
IJavaScriptElementDelta[] children = elementDelta.getAffectedChildren();
for(int i = 0, length = children.length; i < length; i++) {
trimDelta((JavaElementDelta)children[i]);
}
}
}
}