org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/VariableBlock.java - jdt/eclipse.jdt.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2006 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.ui.wizards.buildpaths;

 import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.OperationCanceledException;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.core.runtime.SubProgressMonitor;

 import org.eclipse.core.resources.ResourcesPlugin;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Shell;

 import org.eclipse.jface.dialogs.IDialogConstants;
 import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.jface.dialogs.ProgressMonitorDialog;
 import org.eclipse.jface.operation.IRunnableWithProgress;
 import org.eclipse.jface.viewers.IDoubleClickListener;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.jface.viewers.ViewerSorter;
 import org.eclipse.jface.window.Window;

 import org.eclipse.jdt.core.IClasspathEntry;
 import org.eclipse.jdt.core.IJavaModel;
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.JavaModelException;

 import org.eclipse.jdt.launching.JavaRuntime;

 import org.eclipse.jdt.internal.ui.JavaPlugin;
 import org.eclipse.jdt.internal.ui.util.CoreUtility;
 import org.eclipse.jdt.internal.ui.util.ExceptionHandler;
 import org.eclipse.jdt.internal.ui.wizards.NewWizardMessages;
 import org.eclipse.jdt.internal.ui.wizards.dialogfields.DialogField;
 import org.eclipse.jdt.internal.ui.wizards.dialogfields.IDialogFieldListener;
 import org.eclipse.jdt.internal.ui.wizards.dialogfields.IListAdapter;
 import org.eclipse.jdt.internal.ui.wizards.dialogfields.LayoutUtil;
 import org.eclipse.jdt.internal.ui.wizards.dialogfields.ListDialogField;


 public class VariableBlock {

 	private ListDialogField fVariablesList;
 	private Control fControl;
 	private boolean fHasChanges;

 	private List fSelectedElements;
 	private boolean fAskToBuild;
 	private boolean fInPreferencePage;


 	/**
 	 * Constructor for VariableBlock
 	 */
 	public VariableBlock(boolean inPreferencePage, String initSelection) {

 		fSelectedElements= new ArrayList(0);
 		fInPreferencePage= inPreferencePage;
 		fAskToBuild= true;

 		String[] buttonLabels= new String[] {
 			NewWizardMessages.VariableBlock_vars_add_button,
 			NewWizardMessages.VariableBlock_vars_edit_button,
 			NewWizardMessages.VariableBlock_vars_remove_button
 		};

 		VariablesAdapter adapter= new VariablesAdapter();

 		CPVariableElementLabelProvider labelProvider= new CPVariableElementLabelProvider(!inPreferencePage);

 		fVariablesList= new ListDialogField(adapter, buttonLabels, labelProvider);
 		fVariablesList.setDialogFieldListener(adapter);
 		fVariablesList.setLabelText(NewWizardMessages.VariableBlock_vars_label);
 		fVariablesList.setRemoveButtonIndex(2);

 		fVariablesList.enableButton(1, false);

 		fVariablesList.setViewerSorter(new ViewerSorter() {
 			public int compare(Viewer viewer, Object e1, Object e2) {
 				if (e1 instanceof CPVariableElement && e2 instanceof CPVariableElement) {
 					return ((CPVariableElement)e1).getName().compareTo(((CPVariableElement)e2).getName());
 				}
 				return super.compare(viewer, e1, e2);
 			}
 		});
 		refresh(initSelection);
 	}

 	public boolean hasChanges() {
 		return fHasChanges;
 	}

 	public void setChanges(boolean hasChanges) {
 		fHasChanges= hasChanges;
 	}


 	private String[] getReservedVariableNames() {
 		return new String[] {
 			JavaRuntime.JRELIB_VARIABLE,
 			JavaRuntime.JRESRC_VARIABLE,
 			JavaRuntime.JRESRCROOT_VARIABLE,
 		};
 	}

 	public Control createContents(Composite parent) {
 		Composite composite= new Composite(parent, SWT.NONE);
 		composite.setFont(parent.getFont());

 		LayoutUtil.doDefaultLayout(composite, new DialogField[] { fVariablesList }, true, 0, 0);
 		LayoutUtil.setHorizontalGrabbing(fVariablesList.getListControl(null));

 		fControl= composite;
 		return composite;
 	}

 	public void addDoubleClickListener(IDoubleClickListener listener) {
 		fVariablesList.getTableViewer().addDoubleClickListener(listener);
 	}

 	public void addSelectionChangedListener(ISelectionChangedListener listener) {
 		fVariablesList.getTableViewer().addSelectionChangedListener(listener);
 	}


 	private Shell getShell() {
 		if (fControl != null) {
 			return fControl.getShell();
 		}
 		return JavaPlugin.getActiveWorkbenchShell();
 	}

 	private class VariablesAdapter implements IDialogFieldListener, IListAdapter {

 		// -------- IListAdapter --------

 		public void customButtonPressed(ListDialogField field, int index) {
 			switch (index) {
 			case 0: /* add */
 				editEntries(null);
 				break;
 			case 1: /* edit */
 				List selected= field.getSelectedElements();
 				editEntries((CPVariableElement)selected.get(0));
 				break;
 			}
 		}

 		public void selectionChanged(ListDialogField field) {
 			doSelectionChanged(field);
 		}

 		public void doubleClicked(ListDialogField field) {
 			if (fInPreferencePage) {
 				List selected= field.getSelectedElements();
 				if (canEdit(selected, containsReserved(selected))) {
 					editEntries((CPVariableElement) selected.get(0));
 				}
 			}
 		}

 		// ---------- IDialogFieldListener --------

 		public void dialogFieldChanged(DialogField field) {
 		}

 	}

 	private boolean containsReserved(List selected) {
 		for (int i= selected.size()-1; i >= 0; i--) {
 			if (((CPVariableElement)selected.get(i)).isReserved()) {
 				return true;
 			}
 		}
 		return false;
 	}

 	private static void addAll(Object[] objs, Collection dest) {
 		for (int i= 0; i < objs.length; i++) {
 			dest.add(objs[i]);
 		}
 	}

 	private boolean canEdit(List selected, boolean containsReserved) {
 		return selected.size() == 1 && !containsReserved;
 	}

 	private void doSelectionChanged(DialogField field) {
 		List selected= fVariablesList.getSelectedElements();
 		boolean containsReserved= containsReserved(selected);

 		// edit
 		fVariablesList.enableButton(1, canEdit(selected, containsReserved));
 		// remove button
 		fVariablesList.enableButton(2, !containsReserved);

 		fSelectedElements= selected;
 	}

 	private void editEntries(CPVariableElement entry) {
 		List existingEntries= fVariablesList.getElements();

 		VariableCreationDialog dialog= new VariableCreationDialog(getShell(), entry, existingEntries);
 		if (dialog.open() != Window.OK) {
 			return;
 		}
 		CPVariableElement newEntry= dialog.getClasspathElement();
 		if (entry == null) {
 			fVariablesList.addElement(newEntry);
 			entry= newEntry;
 			fHasChanges= true;
 		} else {
 			boolean hasChanges= !(entry.getName().equals(newEntry.getName()) && entry.getPath().equals(newEntry.getPath()));
 			if (hasChanges) {
 				fHasChanges= true;
 				entry.setName(newEntry.getName());
 				entry.setPath(newEntry.getPath());
 				fVariablesList.refresh();
 			}
 		}
 		fVariablesList.selectElements(new StructuredSelection(entry));
 	}

 	public List getSelectedElements() {
 		return fSelectedElements;
 	}


 	public void performDefaults() {
 		fVariablesList.removeAllElements();
 		String[] reservedName= getReservedVariableNames();
 		for (int i= 0; i < reservedName.length; i++) {
 			CPVariableElement elem= new CPVariableElement(reservedName[i], Path.EMPTY, true);
 			elem.setReserved(true);
 			fVariablesList.addElement(elem);
 		}
 		fHasChanges= true;
 	}

 	public boolean performOk() {
 		ArrayList removedVariables= new ArrayList();
 		ArrayList changedVariables= new ArrayList();
 		removedVariables.addAll(Arrays.asList(JavaCore.getClasspathVariableNames()));

 		// remove all unchanged
 		List changedElements= fVariablesList.getElements();
 		for (int i= changedElements.size()-1; i >= 0; i--) {
 			CPVariableElement curr= (CPVariableElement) changedElements.get(i);
 			if (curr.isReserved()) {
 				changedElements.remove(curr);
 			} else {
 				IPath path= curr.getPath();
 				IPath prevPath= JavaCore.getClasspathVariable(curr.getName());
 				if (prevPath != null && prevPath.equals(path)) {
 					changedElements.remove(curr);
 				} else {
 					changedVariables.add(curr.getName());
 				}
 			}
 			removedVariables.remove(curr.getName());
 		}
 		int steps= changedElements.size() + removedVariables.size();
 		if (steps > 0) {

 			boolean needsBuild= false;
 			if (fAskToBuild && doesChangeRequireFullBuild(removedVariables, changedVariables)) {
 				String title= NewWizardMessages.VariableBlock_needsbuild_title;
 				String message= NewWizardMessages.VariableBlock_needsbuild_message;

 				MessageDialog buildDialog= new MessageDialog(getShell(), title, null, message, MessageDialog.QUESTION, new String[] { IDialogConstants.YES_LABEL, IDialogConstants.NO_LABEL, IDialogConstants.CANCEL_LABEL }, 2);
 				int res= buildDialog.open();
 				if (res != 0 && res != 1) {
 					return false;
 				}
 				needsBuild= (res == 0);
 			}

 			final VariableBlockRunnable runnable= new VariableBlockRunnable(removedVariables, changedElements);
 			final ProgressMonitorDialog dialog= new ProgressMonitorDialog(getShell());
 			try {
 				dialog.run(true, true, runnable);
 			} catch (InvocationTargetException e) {
 				ExceptionHandler.handle(new InvocationTargetException(new NullPointerException()), getShell(), NewWizardMessages.VariableBlock_variableSettingError_titel, NewWizardMessages.VariableBlock_variableSettingError_message);
 				return false;
 			} catch (InterruptedException e) {
 				return false;
 			}

 			if (needsBuild) {
 				CoreUtility.getBuildJob(null).schedule();
 			}
 		}
 		return true;
 	}

 	private boolean doesChangeRequireFullBuild(List removed, List changed) {
 		try {
 			IJavaModel model= JavaCore.create(ResourcesPlugin.getWorkspace().getRoot());
 			IJavaProject[] projects= model.getJavaProjects();
 			for (int i= 0; i < projects.length; i++) {
 				IClasspathEntry[] entries= projects[i].getRawClasspath();
 				for (int k= 0; k < entries.length; k++) {
 					IClasspathEntry curr= entries[k];
 					if (curr.getEntryKind() == IClasspathEntry.CPE_VARIABLE) {
 						String var= curr.getPath().segment(0);
 						if (removed.contains(var) || changed.contains(var)) {
 							return true;
 						}
 					}
 				}
 			}
 		} catch (JavaModelException e) {
 			return true;
 		}
 		return false;
 	}

 	private class VariableBlockRunnable implements IRunnableWithProgress {
 		private List fToRemove;
 		private List fToChange;

 		public VariableBlockRunnable(List toRemove, List toChange) {
 			fToRemove= toRemove;
 			fToChange= toChange;
 		}

 		/*
 	 	 * @see IRunnableWithProgress#run(IProgressMonitor)
 		 */
 		public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException {
 			monitor.beginTask(NewWizardMessages.VariableBlock_operation_desc, 1);
 			try {
 				setVariables(monitor);

 			} catch (CoreException e) {
 				throw new InvocationTargetException(e);
 			} catch (OperationCanceledException e) {
 				throw new InterruptedException();
 			} finally {
 				monitor.done();
 			}
 		}

 		public void setVariables(IProgressMonitor monitor) throws JavaModelException, CoreException {
 			int nVariables= fToChange.size() + fToRemove.size();

 			String[] names= new String[nVariables];
 			IPath[] paths= new IPath[nVariables];
 			int k= 0;

 			for (int i= 0; i < fToChange.size(); i++) {
 				CPVariableElement curr= (CPVariableElement) fToChange.get(i);
 				names[k]= curr.getName();
 				paths[k]= curr.getPath();
 				k++;
 			}
 			for (int i= 0; i < fToRemove.size(); i++) {
 				names[k]= (String) fToRemove.get(i);
 				paths[k]= null;
 				k++;
 			}
 			JavaCore.setClasspathVariables(names, paths, new SubProgressMonitor(monitor, 1));
 		}
 	}

 	/**
 	 * If set to true, a dialog will ask the user to build on variable changed
 	 * @param askToBuild The askToBuild to set
 	 */
 	public void setAskToBuild(boolean askToBuild) {
 		fAskToBuild= askToBuild;
 	}

 	/**
 	 *
 	 */
 	public void refresh(String initSelection) {
 		CPVariableElement initSelectedElement= null;

 		String[] reservedName= getReservedVariableNames();
 		ArrayList reserved= new ArrayList(reservedName.length);
 		addAll(reservedName, reserved);

 		String[] entries= JavaCore.getClasspathVariableNames();
 		ArrayList elements= new ArrayList(entries.length);
 		for (int i= 0; i < entries.length; i++) {
 			String name= entries[i];
 			CPVariableElement elem;
 			IPath entryPath= JavaCore.getClasspathVariable(name);
 			if (entryPath != null) {
 				elem= new CPVariableElement(name, entryPath, reserved.contains(name));
 				elements.add(elem);
 				if (name.equals(initSelection)) {
 					initSelectedElement= elem;
 				}
 			} else {
 				JavaPlugin.logErrorMessage("VariableBlock: Classpath variable with null value: " + name); //$NON-NLS-1$
 			}
 		}

 		fVariablesList.setElements(elements);

 		if (initSelectedElement != null) {
 			ISelection sel= new StructuredSelection(initSelectedElement);
 			fVariablesList.selectElements(sel);
 		} else {
 			fVariablesList.selectFirstElement();
 		}

 		fHasChanges= false;
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2006 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.ui.wizards.buildpaths;

	import java.lang.reflect.InvocationTargetException;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.List;

	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IPath;
	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.core.runtime.OperationCanceledException;
	import org.eclipse.core.runtime.Path;
	import org.eclipse.core.runtime.SubProgressMonitor;

	import org.eclipse.core.resources.ResourcesPlugin;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Shell;

	import org.eclipse.jface.dialogs.IDialogConstants;
	import org.eclipse.jface.dialogs.MessageDialog;
	import org.eclipse.jface.dialogs.ProgressMonitorDialog;
	import org.eclipse.jface.operation.IRunnableWithProgress;
	import org.eclipse.jface.viewers.IDoubleClickListener;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.jface.viewers.Viewer;
	import org.eclipse.jface.viewers.ViewerSorter;
	import org.eclipse.jface.window.Window;

	import org.eclipse.jdt.core.IClasspathEntry;
	import org.eclipse.jdt.core.IJavaModel;
	import org.eclipse.jdt.core.IJavaProject;
	import org.eclipse.jdt.core.JavaCore;
	import org.eclipse.jdt.core.JavaModelException;

	import org.eclipse.jdt.launching.JavaRuntime;

	import org.eclipse.jdt.internal.ui.JavaPlugin;
	import org.eclipse.jdt.internal.ui.util.CoreUtility;
	import org.eclipse.jdt.internal.ui.util.ExceptionHandler;
	import org.eclipse.jdt.internal.ui.wizards.NewWizardMessages;
	import org.eclipse.jdt.internal.ui.wizards.dialogfields.DialogField;
	import org.eclipse.jdt.internal.ui.wizards.dialogfields.IDialogFieldListener;
	import org.eclipse.jdt.internal.ui.wizards.dialogfields.IListAdapter;
	import org.eclipse.jdt.internal.ui.wizards.dialogfields.LayoutUtil;
	import org.eclipse.jdt.internal.ui.wizards.dialogfields.ListDialogField;


	public class VariableBlock {

	private ListDialogField fVariablesList;
	private Control fControl;
	private boolean fHasChanges;

	private List fSelectedElements;
	private boolean fAskToBuild;
	private boolean fInPreferencePage;


	/**
	* Constructor for VariableBlock
	*/
	public VariableBlock(boolean inPreferencePage, String initSelection) {

	fSelectedElements= new ArrayList(0);
	fInPreferencePage= inPreferencePage;
	fAskToBuild= true;

	String[] buttonLabels= new String[] {
	NewWizardMessages.VariableBlock_vars_add_button,
	NewWizardMessages.VariableBlock_vars_edit_button,
	NewWizardMessages.VariableBlock_vars_remove_button
	};

	VariablesAdapter adapter= new VariablesAdapter();

	CPVariableElementLabelProvider labelProvider= new CPVariableElementLabelProvider(!inPreferencePage);

	fVariablesList= new ListDialogField(adapter, buttonLabels, labelProvider);
	fVariablesList.setDialogFieldListener(adapter);
	fVariablesList.setLabelText(NewWizardMessages.VariableBlock_vars_label);
	fVariablesList.setRemoveButtonIndex(2);

	fVariablesList.enableButton(1, false);

	fVariablesList.setViewerSorter(new ViewerSorter() {
	public int compare(Viewer viewer, Object e1, Object e2) {
	if (e1 instanceof CPVariableElement && e2 instanceof CPVariableElement) {
	return ((CPVariableElement)e1).getName().compareTo(((CPVariableElement)e2).getName());
	}
	return super.compare(viewer, e1, e2);
	}
	});
	refresh(initSelection);
	}

	public boolean hasChanges() {
	return fHasChanges;
	}

	public void setChanges(boolean hasChanges) {
	fHasChanges= hasChanges;
	}


	private String[] getReservedVariableNames() {
	return new String[] {
	JavaRuntime.JRELIB_VARIABLE,
	JavaRuntime.JRESRC_VARIABLE,
	JavaRuntime.JRESRCROOT_VARIABLE,
	};
	}

	public Control createContents(Composite parent) {
	Composite composite= new Composite(parent, SWT.NONE);
	composite.setFont(parent.getFont());

	LayoutUtil.doDefaultLayout(composite, new DialogField[] { fVariablesList }, true, 0, 0);
	LayoutUtil.setHorizontalGrabbing(fVariablesList.getListControl(null));

	fControl= composite;
	return composite;
	}

	public void addDoubleClickListener(IDoubleClickListener listener) {
	fVariablesList.getTableViewer().addDoubleClickListener(listener);
	}

	public void addSelectionChangedListener(ISelectionChangedListener listener) {
	fVariablesList.getTableViewer().addSelectionChangedListener(listener);
	}


	private Shell getShell() {
	if (fControl != null) {
	return fControl.getShell();
	}
	return JavaPlugin.getActiveWorkbenchShell();
	}

	private class VariablesAdapter implements IDialogFieldListener, IListAdapter {

	// -------- IListAdapter --------

	public void customButtonPressed(ListDialogField field, int index) {
	switch (index) {
	case 0: /* add */
	editEntries(null);
	break;
	case 1: /* edit */
	List selected= field.getSelectedElements();
	editEntries((CPVariableElement)selected.get(0));
	break;
	}
	}

	public void selectionChanged(ListDialogField field) {
	doSelectionChanged(field);
	}

	public void doubleClicked(ListDialogField field) {
	if (fInPreferencePage) {
	List selected= field.getSelectedElements();
	if (canEdit(selected, containsReserved(selected))) {
	editEntries((CPVariableElement) selected.get(0));
	}
	}
	}

	// ---------- IDialogFieldListener --------

	public void dialogFieldChanged(DialogField field) {
	}

	}

	private boolean containsReserved(List selected) {
	for (int i= selected.size()-1; i >= 0; i--) {
	if (((CPVariableElement)selected.get(i)).isReserved()) {
	return true;
	}
	}
	return false;
	}

	private static void addAll(Object[] objs, Collection dest) {
	for (int i= 0; i < objs.length; i++) {
	dest.add(objs[i]);
	}
	}

	private boolean canEdit(List selected, boolean containsReserved) {
	return selected.size() == 1 && !containsReserved;
	}

	private void doSelectionChanged(DialogField field) {
	List selected= fVariablesList.getSelectedElements();
	boolean containsReserved= containsReserved(selected);

	// edit
	fVariablesList.enableButton(1, canEdit(selected, containsReserved));
	// remove button
	fVariablesList.enableButton(2, !containsReserved);

	fSelectedElements= selected;
	}

	private void editEntries(CPVariableElement entry) {
	List existingEntries= fVariablesList.getElements();

	VariableCreationDialog dialog= new VariableCreationDialog(getShell(), entry, existingEntries);
	if (dialog.open() != Window.OK) {
	return;
	}
	CPVariableElement newEntry= dialog.getClasspathElement();
	if (entry == null) {
	fVariablesList.addElement(newEntry);
	entry= newEntry;
	fHasChanges= true;
	} else {
	boolean hasChanges= !(entry.getName().equals(newEntry.getName()) && entry.getPath().equals(newEntry.getPath()));
	if (hasChanges) {
	fHasChanges= true;
	entry.setName(newEntry.getName());
	entry.setPath(newEntry.getPath());
	fVariablesList.refresh();
	}
	}
	fVariablesList.selectElements(new StructuredSelection(entry));
	}

	public List getSelectedElements() {
	return fSelectedElements;
	}


	public void performDefaults() {
	fVariablesList.removeAllElements();
	String[] reservedName= getReservedVariableNames();
	for (int i= 0; i < reservedName.length; i++) {
	CPVariableElement elem= new CPVariableElement(reservedName[i], Path.EMPTY, true);
	elem.setReserved(true);
	fVariablesList.addElement(elem);
	}
	fHasChanges= true;
	}

	public boolean performOk() {
	ArrayList removedVariables= new ArrayList();
	ArrayList changedVariables= new ArrayList();
	removedVariables.addAll(Arrays.asList(JavaCore.getClasspathVariableNames()));

	// remove all unchanged
	List changedElements= fVariablesList.getElements();
	for (int i= changedElements.size()-1; i >= 0; i--) {
	CPVariableElement curr= (CPVariableElement) changedElements.get(i);
	if (curr.isReserved()) {
	changedElements.remove(curr);
	} else {
	IPath path= curr.getPath();
	IPath prevPath= JavaCore.getClasspathVariable(curr.getName());
	if (prevPath != null && prevPath.equals(path)) {
	changedElements.remove(curr);
	} else {
	changedVariables.add(curr.getName());
	}
	}
	removedVariables.remove(curr.getName());
	}
	int steps= changedElements.size() + removedVariables.size();
	if (steps > 0) {

	boolean needsBuild= false;
	if (fAskToBuild && doesChangeRequireFullBuild(removedVariables, changedVariables)) {
	String title= NewWizardMessages.VariableBlock_needsbuild_title;
	String message= NewWizardMessages.VariableBlock_needsbuild_message;

	MessageDialog buildDialog= new MessageDialog(getShell(), title, null, message, MessageDialog.QUESTION, new String[] { IDialogConstants.YES_LABEL, IDialogConstants.NO_LABEL, IDialogConstants.CANCEL_LABEL }, 2);
	int res= buildDialog.open();
	if (res != 0 && res != 1) {
	return false;
	}
	needsBuild= (res == 0);
	}

	final VariableBlockRunnable runnable= new VariableBlockRunnable(removedVariables, changedElements);
	final ProgressMonitorDialog dialog= new ProgressMonitorDialog(getShell());
	try {
	dialog.run(true, true, runnable);
	} catch (InvocationTargetException e) {
	ExceptionHandler.handle(new InvocationTargetException(new NullPointerException()), getShell(), NewWizardMessages.VariableBlock_variableSettingError_titel, NewWizardMessages.VariableBlock_variableSettingError_message);
	return false;
	} catch (InterruptedException e) {
	return false;
	}

	if (needsBuild) {
	CoreUtility.getBuildJob(null).schedule();
	}
	}
	return true;
	}

	private boolean doesChangeRequireFullBuild(List removed, List changed) {
	try {
	IJavaModel model= JavaCore.create(ResourcesPlugin.getWorkspace().getRoot());
	IJavaProject[] projects= model.getJavaProjects();
	for (int i= 0; i < projects.length; i++) {
	IClasspathEntry[] entries= projects[i].getRawClasspath();
	for (int k= 0; k < entries.length; k++) {
	IClasspathEntry curr= entries[k];
	if (curr.getEntryKind() == IClasspathEntry.CPE_VARIABLE) {
	String var= curr.getPath().segment(0);
	if (removed.contains(var) \|\| changed.contains(var)) {
	return true;
	}
	}
	}
	}
	} catch (JavaModelException e) {
	return true;
	}
	return false;
	}

	private class VariableBlockRunnable implements IRunnableWithProgress {
	private List fToRemove;
	private List fToChange;

	public VariableBlockRunnable(List toRemove, List toChange) {
	fToRemove= toRemove;
	fToChange= toChange;
	}

	/*
	* @see IRunnableWithProgress#run(IProgressMonitor)
	*/
	public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException {
	monitor.beginTask(NewWizardMessages.VariableBlock_operation_desc, 1);
	try {
	setVariables(monitor);

	} catch (CoreException e) {
	throw new InvocationTargetException(e);
	} catch (OperationCanceledException e) {
	throw new InterruptedException();
	} finally {
	monitor.done();
	}
	}

	public void setVariables(IProgressMonitor monitor) throws JavaModelException, CoreException {
	int nVariables= fToChange.size() + fToRemove.size();

	String[] names= new String[nVariables];
	IPath[] paths= new IPath[nVariables];
	int k= 0;

	for (int i= 0; i < fToChange.size(); i++) {
	CPVariableElement curr= (CPVariableElement) fToChange.get(i);
	names[k]= curr.getName();
	paths[k]= curr.getPath();
	k++;
	}
	for (int i= 0; i < fToRemove.size(); i++) {
	names[k]= (String) fToRemove.get(i);
	paths[k]= null;
	k++;
	}
	JavaCore.setClasspathVariables(names, paths, new SubProgressMonitor(monitor, 1));
	}
	}

	/**
	* If set to true, a dialog will ask the user to build on variable changed
	* @param askToBuild The askToBuild to set
	*/
	public void setAskToBuild(boolean askToBuild) {
	fAskToBuild= askToBuild;
	}

	/**
	*
	*/
	public void refresh(String initSelection) {
	CPVariableElement initSelectedElement= null;

	String[] reservedName= getReservedVariableNames();
	ArrayList reserved= new ArrayList(reservedName.length);
	addAll(reservedName, reserved);

	String[] entries= JavaCore.getClasspathVariableNames();
	ArrayList elements= new ArrayList(entries.length);
	for (int i= 0; i < entries.length; i++) {
	String name= entries[i];
	CPVariableElement elem;
	IPath entryPath= JavaCore.getClasspathVariable(name);
	if (entryPath != null) {
	elem= new CPVariableElement(name, entryPath, reserved.contains(name));
	elements.add(elem);
	if (name.equals(initSelection)) {
	initSelectedElement= elem;
	}
	} else {
	JavaPlugin.logErrorMessage("VariableBlock: Classpath variable with null value: " + name); //$NON-NLS-1$
	}
	}

	fVariablesList.setElements(elements);

	if (initSelectedElement != null) {
	ISelection sel= new StructuredSelection(initSelectedElement);
	fVariablesList.selectElements(sel);
	} else {
	fVariablesList.selectFirstElement();
	}

	fHasChanges= false;
	}

	}