Java tutorial
/******************************************************************************* * 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.ui.dialogs; import java.util.Arrays; import java.util.List; import org.eclipse.core.resources.IContainer; import org.eclipse.core.runtime.IPath; import org.eclipse.core.runtime.Path; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.dialogs.MessageDialog; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.wizard.WizardPage; import org.eclipse.osgi.util.NLS; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Group; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Text; import org.eclipse.ui.internal.ide.IDEWorkbenchMessages; /** * The common superclass for wizard import and export pages. * <p> * This class is not intended to be subclassed outside of the workbench. * </p> * @noextend This class is not intended to be subclassed by clients. */ public abstract class WizardDataTransferPage extends WizardPage implements Listener, IOverwriteQuery { // constants protected static final int SIZING_TEXT_FIELD_WIDTH = 250; protected static final int COMBO_HISTORY_LENGTH = 5; /** * Creates a new wizard page. * * @param pageName the name of the page */ protected WizardDataTransferPage(String pageName) { super(pageName); } /** * Adds an entry to a history, while taking care of duplicate history items * and excessively long histories. The assumption is made that all histories * should be of length <code>WizardDataTransferPage.COMBO_HISTORY_LENGTH</code>. * * @param history the current history * @param newEntry the entry to add to the history */ protected String[] addToHistory(String[] history, String newEntry) { java.util.ArrayList l = new java.util.ArrayList(Arrays.asList(history)); addToHistory(l, newEntry); String[] r = new String[l.size()]; l.toArray(r); return r; } /** * Adds an entry to a history, while taking care of duplicate history items * and excessively long histories. The assumption is made that all histories * should be of length <code>WizardDataTransferPage.COMBO_HISTORY_LENGTH</code>. * * @param history the current history * @param newEntry the entry to add to the history */ protected void addToHistory(List history, String newEntry) { history.remove(newEntry); history.add(0, newEntry); // since only one new item was added, we can be over the limit // by at most one item if (history.size() > COMBO_HISTORY_LENGTH) { history.remove(COMBO_HISTORY_LENGTH); } } /** * Return whether the user is allowed to enter a new container name or just * choose from existing ones. * <p> * Subclasses must implement this method. * </p> * * @return <code>true</code> if new ones are okay, and <code>false</code> * if only existing ones are allowed */ protected abstract boolean allowNewContainerName(); /** * Creates a new label with a bold font. * * @param parent the parent control * @param text the label text * @return the new label control */ protected Label createBoldLabel(Composite parent, String text) { Label label = new Label(parent, SWT.NONE); label.setFont(JFaceResources.getBannerFont()); label.setText(text); GridData data = new GridData(); data.verticalAlignment = GridData.FILL; data.horizontalAlignment = GridData.FILL; label.setLayoutData(data); return label; } /** * Creates the import/export options group controls. * <p> * The <code>WizardDataTransferPage</code> implementation of this method does * nothing. Subclasses wishing to define such components should reimplement * this hook method. * </p> * * @param optionsGroup the parent control */ protected void createOptionsGroupButtons(Group optionsGroup) { } /** * Creates a new label with a bold font. * * @param parent the parent control * @param text the label text * @return the new label control */ protected Label createPlainLabel(Composite parent, String text) { Label label = new Label(parent, SWT.NONE); label.setText(text); label.setFont(parent.getFont()); GridData data = new GridData(); data.verticalAlignment = GridData.FILL; data.horizontalAlignment = GridData.FILL; label.setLayoutData(data); return label; } /** * Creates a horizontal spacer line that fills the width of its container. * * @param parent the parent control */ protected void createSpacer(Composite parent) { Label spacer = new Label(parent, SWT.NONE); GridData data = new GridData(); data.horizontalAlignment = GridData.FILL; data.verticalAlignment = GridData.BEGINNING; spacer.setLayoutData(data); } /** * Returns whether this page is complete. This determination is made based upon * the current contents of this page's controls. Subclasses wishing to include * their controls in this determination should override the hook methods * <code>validateSourceGroup</code> and/or <code>validateOptionsGroup</code>. * * @return <code>true</code> if this page is complete, and <code>false</code> if * incomplete * @see #validateSourceGroup * @see #validateOptionsGroup */ protected boolean determinePageCompletion() { boolean complete = validateSourceGroup() && validateDestinationGroup() && validateOptionsGroup(); // Avoid draw flicker by not clearing the error // message unless all is valid. if (complete) { setErrorMessage(null); } return complete; } /** * Get a path from the supplied text widget. * @return org.eclipse.core.runtime.IPath */ protected IPath getPathFromText(Text textField) { String text = textField.getText(); //Do not make an empty path absolute so as not to confuse with the root if (text.length() == 0) { return new Path(text); } return (new Path(text)).makeAbsolute(); } /** * Queries the user to supply a container resource. * * @return the path to an existing or new container, or <code>null</code> if the * user cancelled the dialog */ protected IPath queryForContainer(IContainer initialSelection, String msg) { return queryForContainer(initialSelection, msg, null); } /** * Queries the user to supply a container resource. * * @return the path to an existing or new container, or <code>null</code> if the * user cancelled the dialog */ protected IPath queryForContainer(IContainer initialSelection, String msg, String title) { ContainerSelectionDialog dialog = new ContainerSelectionDialog(getControl().getShell(), initialSelection, allowNewContainerName(), msg); if (title != null) { dialog.setTitle(title); } dialog.showClosedProjects(false); dialog.open(); Object[] result = dialog.getResult(); if (result != null && result.length == 1) { return (IPath) result[0]; } return null; } /** * The <code>WizardDataTransfer</code> implementation of this * <code>IOverwriteQuery</code> method asks the user whether the existing * resource at the given path should be overwritten. * * @param pathString * @return the user's reply: one of <code>"YES"</code>, <code>"NO"</code>, <code>"ALL"</code>, * or <code>"CANCEL"</code> */ public String queryOverwrite(String pathString) { Path path = new Path(pathString); String messageString; //Break the message up if there is a file name and a directory //and there are at least 2 segments. if (path.getFileExtension() == null || path.segmentCount() < 2) { messageString = NLS.bind(IDEWorkbenchMessages.WizardDataTransfer_existsQuestion, pathString); } else { messageString = NLS.bind(IDEWorkbenchMessages.WizardDataTransfer_overwriteNameAndPathQuestion, path.lastSegment(), path.removeLastSegments(1).toOSString()); } final MessageDialog dialog = new MessageDialog(getContainer().getShell(), IDEWorkbenchMessages.Question, null, messageString, MessageDialog.QUESTION, new String[] { IDialogConstants.YES_LABEL, IDialogConstants.YES_TO_ALL_LABEL, IDialogConstants.NO_LABEL, IDialogConstants.NO_TO_ALL_LABEL, IDialogConstants.CANCEL_LABEL }, 0) { protected int getShellStyle() { return super.getShellStyle() | SWT.SHEET; } }; String[] response = new String[] { YES, ALL, NO, NO_ALL, CANCEL }; //run in syncExec because callback is from an operation, //which is probably not running in the UI thread. getControl().getDisplay().syncExec(new Runnable() { public void run() { dialog.open(); } }); return dialog.getReturnCode() < 0 ? CANCEL : response[dialog.getReturnCode()]; } /** * Displays a Yes/No question to the user with the specified message and returns * the user's response. * * @param message the question to ask * @return <code>true</code> for Yes, and <code>false</code> for No */ protected boolean queryYesNoQuestion(String message) { MessageDialog dialog = new MessageDialog(getContainer().getShell(), IDEWorkbenchMessages.Question, (Image) null, message, MessageDialog.NONE, new String[] { IDialogConstants.YES_LABEL, IDialogConstants.NO_LABEL }, 0) { protected int getShellStyle() { return super.getShellStyle() | SWT.SHEET; } }; // ensure yes is the default return dialog.open() == 0; } /** * Restores control settings that were saved in the previous instance of this * page. * <p> * The <code>WizardDataTransferPage</code> implementation of this method does * nothing. Subclasses may override this hook method. * </p> */ protected void restoreWidgetValues() { } /** * Saves control settings that are to be restored in the next instance of * this page. * <p> * The <code>WizardDataTransferPage</code> implementation of this method does * nothing. Subclasses may override this hook method. * </p> */ protected void saveWidgetValues() { } /** * Determine if the page is complete and update the page appropriately. */ protected void updatePageCompletion() { boolean pageComplete = determinePageCompletion(); setPageComplete(pageComplete); if (pageComplete) { setErrorMessage(null); } } /** * Updates the enable state of this page's controls. * <p> * The <code>WizardDataTransferPage</code> implementation of this method does * nothing. Subclasses may extend this hook method. * </p> */ protected void updateWidgetEnablements() { } /** * Returns whether this page's destination specification controls currently all * contain valid values. * <p> * The <code>WizardDataTransferPage</code> implementation of this method returns * <code>true</code>. Subclasses may reimplement this hook method. * </p> * * @return <code>true</code> indicating validity of all controls in the * destination specification group */ protected boolean validateDestinationGroup() { return true; } /** * Returns whether this page's options group's controls currently all contain * valid values. * <p> * The <code>WizardDataTransferPage</code> implementation of this method returns * <code>true</code>. Subclasses may reimplement this hook method. * </p> * * @return <code>true</code> indicating validity of all controls in the options * group */ protected boolean validateOptionsGroup() { return true; } /** * Returns whether this page's source specification controls currently all * contain valid values. * <p> * The <code>WizardDataTransferPage</code> implementation of this method returns * <code>true</code>. Subclasses may reimplement this hook method. * </p> * * @return <code>true</code> indicating validity of all controls in the * source specification group */ protected boolean validateSourceGroup() { return true; } /** * Create the options specification widgets. * * @param parent org.eclipse.swt.widgets.Composite */ protected void createOptionsGroup(Composite parent) { // options group Group optionsGroup = new Group(parent, SWT.NONE); GridLayout layout = new GridLayout(); optionsGroup.setLayout(layout); optionsGroup.setLayoutData(new GridData(GridData.HORIZONTAL_ALIGN_FILL | GridData.GRAB_HORIZONTAL)); optionsGroup.setText(IDEWorkbenchMessages.WizardExportPage_options); optionsGroup.setFont(parent.getFont()); createOptionsGroupButtons(optionsGroup); } /** * Display an error dialog with the specified message. * * @param message the error message */ protected void displayErrorDialog(String message) { MessageDialog.open(MessageDialog.ERROR, getContainer().getShell(), getErrorDialogTitle(), message, SWT.SHEET); } /** * Display an error dislog with the information from the * supplied exception. * @param exception Throwable */ protected void displayErrorDialog(Throwable exception) { String message = exception.getMessage(); //Some system exceptions have no message if (message == null) { message = NLS.bind(IDEWorkbenchMessages.WizardDataTransfer_exceptionMessage, exception); } displayErrorDialog(message); } /** * Get the title for an error dialog. Subclasses should * override. */ protected String getErrorDialogTitle() { return IDEWorkbenchMessages.WizardExportPage_internalErrorTitle; } }