/*******************************************************************************
* 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.jdt.internal.core;
import java.util.HashSet;
import java.util.Iterator;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaElementDelta;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaModelException;
/**
* This class is used by <code>JavaModelManager</code> to update the JavaModel based on some
* <code>IJavaElementDelta</code>s.
*/
public class ModelUpdater {
HashSet projectsToUpdate= new HashSet();
/**
* Adds the given child handle to its parent's cache of children.
*/
protected void addToParentInfo(Openable child) {
Openable parent= (Openable)child.getParent();
if (parent != null && parent.isOpen()) {
try {
OpenableElementInfo info= (OpenableElementInfo)parent.getElementInfo();
info.addChild(child);
} catch (JavaModelException e) {
// do nothing - we already checked if open
}
}
}
/**
* Closes the given element, which removes it from the cache of open elements.
*/
protected static void close(Openable element) {
try {
element.close();
} catch (JavaModelException e) {
// do nothing
}
}
/**
* Processing for an element that has been added:
* <ul>
* <li>If the element is a project, do nothing, and do not process children, as when a project
* is created it does not yet have any natures - specifically a java nature.
* <li>If the elemet is not a project, process it as added (see <code>basicElementAdded</code>.
* </ul>
*/
protected void elementAdded(Openable element) {
int elementType= element.getElementType();
if (elementType == IJavaElement.JAVA_PROJECT) {
// project add is handled by JavaProject.configure() because
// when a project is created, it does not yet have a java nature
addToParentInfo(element);
this.projectsToUpdate.add(element);
} else {
addToParentInfo(element);
// Force the element to be closed as it might have been opened
// before the resource modification came in and it might have a new child
// For example, in an IWorkspaceRunnable:
// 1. create a package fragment p using a java model operation
// 2. open package p
// 3. add file X.java in folder p
// When the resource delta comes in, only the addition of p is notified,
// but the package p is already opened, thus its children are not recomputed
// and it appears empty.
close(element);
}
switch (elementType) {
case IJavaElement.PACKAGE_FRAGMENT_ROOT:
// when a root is added, and is on the classpath, the project must be updated
this.projectsToUpdate.add(element.getJavaProject());
break;
case IJavaElement.PACKAGE_FRAGMENT:
// get rid of package fragment cache
JavaProject project= (JavaProject)element.getJavaProject();
project.resetCaches();
break;
}
}
/**
* Generic processing for elements with changed contents:
* <ul>
* <li>The element is closed such that any subsequent accesses will re-open the element
* reflecting its new structure.
* </ul>
*/
protected void elementChanged(Openable element) {
close(element);
}
/**
* Generic processing for a removed element:
* <ul>
* <li>Close the element, removing its structure from the cache
* <li>Remove the element from its parent's cache of children
* <li>Add a REMOVED entry in the delta
* </ul>
*/
protected void elementRemoved(Openable element) {
if (element.isOpen()) {
close(element);
}
removeFromParentInfo(element);
int elementType= element.getElementType();
switch (elementType) {
case IJavaElement.JAVA_MODEL:
JavaModelManager.getIndexManager().reset();
break;
case IJavaElement.JAVA_PROJECT:
JavaModelManager manager= JavaModelManager.getJavaModelManager();
JavaProject javaProject= (JavaProject)element;
manager.removePerProjectInfo(javaProject);
manager.containerRemove(javaProject);
break;
case IJavaElement.PACKAGE_FRAGMENT_ROOT:
this.projectsToUpdate.add(element.getJavaProject());
break;
case IJavaElement.PACKAGE_FRAGMENT:
// get rid of package fragment cache
JavaProject project= (JavaProject)element.getJavaProject();
project.resetCaches();
break;
}
}
/**
* Converts a <code>IResourceDelta</code> rooted in a <code>Workspace</code> into the
* corresponding set of <code>IJavaElementDelta</code>, rooted in the relevant
* <code>JavaModel</code>s.
*/
public void processJavaDelta(IJavaElementDelta delta) {
try {
traverseDelta(delta, null, null); // traverse delta
// reset project caches of projects that were affected
Iterator iterator= this.projectsToUpdate.iterator();
while (iterator.hasNext()) {
JavaProject project= (JavaProject)iterator.next();
project.resetCaches();
}
} finally {
this.projectsToUpdate= new HashSet();
}
}
/**
* Removes the given element from its parents cache of children. If the element does not have a
* parent, or the parent is not currently open, this has no effect.
*/
protected void removeFromParentInfo(Openable child) {
Openable parent= (Openable)child.getParent();
if (parent != null && parent.isOpen()) {
try {
OpenableElementInfo info= (OpenableElementInfo)parent.getElementInfo();
info.removeChild(child);
} catch (JavaModelException e) {
// do nothing - we already checked if open
}
}
}
/**
* Converts an <code>IResourceDelta</code> and its children into the corresponding
* <code>IJavaElementDelta</code>s. Return whether the delta corresponds to a resource on the
* classpath. If it is not a resource on the classpath, it will be added as a non-java resource
* by the sender of this method.
*/
protected void traverseDelta(
IJavaElementDelta delta,
IPackageFragmentRoot root,
IJavaProject project) {
boolean processChildren= true;
Openable element= (Openable)delta.getElement();
switch (element.getElementType()) {
case IJavaElement.JAVA_PROJECT:
project= (IJavaProject)element;
break;
case IJavaElement.PACKAGE_FRAGMENT_ROOT:
root= (IPackageFragmentRoot)element;
break;
case IJavaElement.COMPILATION_UNIT:
// filter out working copies that are not primary (we don't want to add/remove them to/from the package fragment
CompilationUnit cu= (CompilationUnit)element;
if (cu.isWorkingCopy() && !cu.isPrimary()) {
return;
}
// $FALL-THROUGH$
case IJavaElement.CLASS_FILE:
processChildren= false;
break;
}
switch (delta.getKind()) {
case IJavaElementDelta.ADDED:
elementAdded(element);
break;
case IJavaElementDelta.REMOVED:
elementRemoved(element);
break;
case IJavaElementDelta.CHANGED:
if ((delta.getFlags() & IJavaElementDelta.F_CONTENT) != 0) {
elementChanged(element);
}
break;
}
if (processChildren) {
IJavaElementDelta[] children= delta.getAffectedChildren();
for (int i= 0; i < children.length; i++) {
IJavaElementDelta childDelta= children[i];
traverseDelta(childDelta, root, project);
}
}
}
}