/*******************************************************************************
* 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.wst.jsdt.internal.core;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.jobs.ISchedulingRule;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.text.edits.TextEdit;
import org.eclipse.wst.jsdt.core.IJavaScriptUnit;
import org.eclipse.wst.jsdt.core.IJavaScriptElement;
import org.eclipse.wst.jsdt.core.IJavaScriptModelStatusConstants;
import org.eclipse.wst.jsdt.core.IRegion;
import org.eclipse.wst.jsdt.core.JavaScriptModelException;
import org.eclipse.wst.jsdt.core.dom.AST;
import org.eclipse.wst.jsdt.core.dom.ASTNode;
import org.eclipse.wst.jsdt.core.dom.ASTParser;
import org.eclipse.wst.jsdt.core.dom.JavaScriptUnit;
import org.eclipse.wst.jsdt.core.dom.rewrite.ASTRewrite;
import org.eclipse.wst.jsdt.internal.core.util.Messages;
/**
* This operation deletes a collection of elements (and
* all of their children).
* If an element does not exist, it is ignored.
*
* <p>NOTE: This operation only deletes elements contained within leaf resources -
* that is, elements within compilation units. To delete a compilation unit or
* a package, etc (which have an actual resource), a DeleteResourcesOperation
* should be used.
*/
public class DeleteElementsOperation extends MultiOperation {
/**
* The elements this operation processes grouped by compilation unit
* @see #processElements() Keys are compilation units,
* values are <code>IRegion</code>s of elements to be processed in each
* compilation unit.
*/
protected Map childrenToRemove;
/**
* The <code>ASTParser</code> used to manipulate the source code of
* <code>IJavaScriptUnit</code>.
*/
protected ASTParser parser;
/**
* When executed, this operation will delete the given elements. The elements
* to delete cannot be <code>null</code> or empty, and must be contained within a
* compilation unit.
*/
public DeleteElementsOperation(IJavaScriptElement[] elementsToDelete, boolean force) {
super(elementsToDelete, force);
initASTParser();
}
private void deleteElement(IJavaScriptElement elementToRemove, IJavaScriptUnit cu) throws JavaScriptModelException {
// ensure cu is consistent (noop if already consistent)
cu.makeConsistent(this.progressMonitor);
this.parser.setSource(cu);
JavaScriptUnit astCU = (JavaScriptUnit) this.parser.createAST(this.progressMonitor);
ASTNode node = ((JavaElement) elementToRemove).findNode(astCU);
if (node == null)
Assert.isTrue(false, "Failed to locate " + elementToRemove.getElementName() + " in " + cu.getElementName()); //$NON-NLS-1$//$NON-NLS-2$
IDocument document = getDocument(cu);
AST ast = astCU.getAST();
ASTRewrite rewriter = ASTRewrite.create(ast);
rewriter.remove(node, null);
TextEdit edits = rewriter.rewriteAST(document, null);
try {
edits.apply(document);
} catch (BadLocationException e) {
throw new JavaScriptModelException(e, IJavaScriptModelStatusConstants.INVALID_CONTENTS);
}
}
private void initASTParser() {
this.parser = ASTParser.newParser(AST.JLS3);
}
/**
* @see MultiOperation
*/
protected String getMainTaskName() {
return Messages.operation_deleteElementProgress;
}
protected ISchedulingRule getSchedulingRule() {
if (this.elementsToProcess != null && this.elementsToProcess.length == 1) {
IResource resource = this.elementsToProcess[0].getResource();
if (resource != null)
return ResourcesPlugin.getWorkspace().getRuleFactory().modifyRule(resource);
}
return super.getSchedulingRule();
}
/**
* Groups the elements to be processed by their compilation unit.
* If parent/child combinations are present, children are
* discarded (only the parents are processed). Removes any
* duplicates specified in elements to be processed.
*/
protected void groupElements() throws JavaScriptModelException {
childrenToRemove = new HashMap(1);
int uniqueCUs = 0;
for (int i = 0, length = elementsToProcess.length; i < length; i++) {
IJavaScriptElement e = elementsToProcess[i];
IJavaScriptUnit cu = getCompilationUnitFor(e);
if (cu == null) {
throw new JavaScriptModelException(new JavaModelStatus(IJavaScriptModelStatusConstants.READ_ONLY, e));
} else {
IRegion region = (IRegion) childrenToRemove.get(cu);
if (region == null) {
region = new Region();
childrenToRemove.put(cu, region);
uniqueCUs += 1;
}
region.add(e);
}
}
elementsToProcess = new IJavaScriptElement[uniqueCUs];
Iterator iter = childrenToRemove.keySet().iterator();
int i = 0;
while (iter.hasNext()) {
elementsToProcess[i++] = (IJavaScriptElement) iter.next();
}
}
/**
* Deletes this element from its compilation unit.
* @see MultiOperation
*/
protected void processElement(IJavaScriptElement element) throws JavaScriptModelException {
IJavaScriptUnit cu = (IJavaScriptUnit) element;
// keep track of the import statements - if all are removed, delete
// the import container (and report it in the delta)
int numberOfImports = cu.getImports().length;
JavaElementDelta delta = new JavaElementDelta(cu);
IJavaScriptElement[] cuElements = ((IRegion) childrenToRemove.get(cu)).getElements();
for (int i = 0, length = cuElements.length; i < length; i++) {
IJavaScriptElement e = cuElements[i];
if (e.exists()) {
deleteElement(e, cu);
delta.removed(e);
if (e.getElementType() == IJavaScriptElement.IMPORT_DECLARATION) {
numberOfImports--;
if (numberOfImports == 0) {
delta.removed(cu.getImportContainer());
}
}
}
}
if (delta.getAffectedChildren().length > 0) {
cu.save(getSubProgressMonitor(1), force);
if (!cu.isWorkingCopy()) { // if unit is working copy, then save will have already fired the delta
addDelta(delta);
setAttribute(HAS_MODIFIED_RESOURCE_ATTR, TRUE);
}
}
}
/**
* @see MultiOperation
* This method first group the elements by <code>IJavaScriptUnit</code>,
* and then processes the <code>IJavaScriptUnit</code>.
*/
protected void processElements() throws JavaScriptModelException {
groupElements();
super.processElements();
}
/**
* @see MultiOperation
*/
protected void verify(IJavaScriptElement element) throws JavaScriptModelException {
IJavaScriptElement[] children = ((IRegion) childrenToRemove.get(element)).getElements();
for (int i = 0; i < children.length; i++) {
IJavaScriptElement child = children[i];
if (child.getCorrespondingResource() != null)
error(IJavaScriptModelStatusConstants.INVALID_ELEMENT_TYPES, child);
if (child.isReadOnly())
error(IJavaScriptModelStatusConstants.READ_ONLY, child);
}
}
}