Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2015 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 * Sebastian Davids <sdavids@gmx.de> - Fix for bug 19346 - Dialog font should * be activated and used by other components. * Krzysztof Daniel <krzysztof.daniel@gmail.com> Bug 96373 - [ErrorHandling] * ErrorDialog details area becomes huge with multi-line strings * Jan-Ove Weichel <janove.weichel@vogella.com> - Bug 475879 *******************************************************************************/ package org.eclipse.jface.dialogs; import java.io.BufferedReader; import java.io.IOException; import java.io.StringReader; import java.util.ArrayList; import java.util.Iterator; import org.eclipse.core.runtime.CoreException; import org.eclipse.core.runtime.IStatus; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.util.Policy; import org.eclipse.swt.SWT; import org.eclipse.swt.dnd.Clipboard; import org.eclipse.swt.dnd.TextTransfer; import org.eclipse.swt.dnd.Transfer; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.List; import org.eclipse.swt.widgets.Menu; import org.eclipse.swt.widgets.MenuItem; import org.eclipse.swt.widgets.Shell; /** * A dialog to display one or more errors to the user, as contained in an * <code>IStatus</code> object. If an error contains additional detailed * information then a Details button is automatically supplied, which shows or * hides an error details viewer when pressed by the user. * * <p> * This dialog should be considered being a "local" way of error handling. It * cannot be changed or replaced by "global" error handling facility ( * <code>org.eclipse.ui.statushandler.StatusManager</code>). If product defines * its own way of handling errors, this error dialog may cause UI inconsistency, * so until it is absolutely necessary, <code>StatusManager</code> should be * used. * </p> * * @see org.eclipse.core.runtime.IStatus */ public class ErrorDialog extends IconAndMessageDialog { /** * Static to prevent opening of error dialogs for automated testing. */ public static boolean AUTOMATED_MODE = false; /** * The nesting indent. */ private static final String NESTING_INDENT = " "; //$NON-NLS-1$ /** * The Details button. */ private Button detailsButton; /** * The title of the dialog. */ private String title; /** * The SWT list control that displays the error details. */ private List list; /** * Indicates whether the error details viewer is currently created. */ private boolean listCreated = false; /** * Filter mask for determining which status items to display. */ private int displayMask = 0xFFFF; /** * The main status object. */ private IStatus status; /** * The current clipboard. To be disposed when closing the dialog. */ private Clipboard clipboard; private boolean shouldIncludeTopLevelErrorInDetails = false; /** * Creates an error dialog. Note that the dialog will have no visual * representation (no widgets) until it is told to open. * <p> * Normally one should use <code>openError</code> to create and open one * of these. This constructor is useful only if the error object being * displayed contains child items <it>and </it> you need to specify a mask * which will be used to filter the displaying of these children. The error * dialog will only be displayed if there is at least one child status * matching the mask. * </p> * * @param parentShell * the shell under which to create this dialog * @param dialogTitle * the title to use for this dialog, or <code>null</code> to * indicate that the default title should be used * @param message * the message to show in this dialog, or <code>null</code> to * indicate that the error's message should be shown as the * primary message * @param status * the error to show to the user * @param displayMask * the mask to use to filter the displaying of child items, as * per <code>IStatus.matches</code> * @see org.eclipse.core.runtime.IStatus#matches(int) */ public ErrorDialog(Shell parentShell, String dialogTitle, String message, IStatus status, int displayMask) { super(parentShell); this.title = dialogTitle == null ? JFaceResources.getString("Problem_Occurred") : //$NON-NLS-1$ dialogTitle; this.message = message == null ? status.getMessage() : JFaceResources.format("Reason", message, status.getMessage()); //$NON-NLS-1$ this.status = status; this.displayMask = displayMask; } /* * Handles the pressing of the Ok or Details button in this dialog. If the * Ok button was pressed then close this dialog. If the Details button was * pressed then toggle the displaying of the error details area. Note that * the Details button will only be visible if the error being displayed * specifies child details. */ @Override protected void buttonPressed(int id) { if (id == IDialogConstants.DETAILS_ID) { // was the details button pressed? toggleDetailsArea(); } else { super.buttonPressed(id); } } @Override protected void configureShell(Shell shell) { super.configureShell(shell); shell.setText(title); } @Override protected void createButtonsForButtonBar(Composite parent) { // create OK and Details buttons createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL, true); createDetailsButton(parent); } /** * Create the area for extra error support information. * * @param parent */ private void createSupportArea(Composite parent) { ErrorSupportProvider provider = Policy.getErrorSupportProvider(); if (provider == null) return; if (!provider.validFor(status)) { return; } Composite supportArea = new Composite(parent, SWT.NONE); provider.createSupportArea(supportArea, status); GridData supportData = new GridData(SWT.FILL, SWT.FILL, true, true); supportData.verticalSpan = 3; supportArea.setLayoutData(supportData); if (supportArea.getLayout() == null) { GridLayout layout = new GridLayout(); layout.marginWidth = 0; layout.marginHeight = 0; supportArea.setLayout(layout); // Give it a default layout if one isn't set } } /** * Create the details button if it should be included. * * @param parent * the parent composite * @since 3.2 */ protected void createDetailsButton(Composite parent) { if (shouldShowDetailsButton()) { detailsButton = createButton(parent, IDialogConstants.DETAILS_ID, IDialogConstants.SHOW_DETAILS_LABEL, false); } } /** * This implementation of the <code>Dialog</code> framework method creates * and lays out a composite. Subclasses that require a different dialog area * may either override this method, or call the <code>super</code> * implementation and add controls to the created composite. * * Note: Since 3.4, the created composite no longer grabs excess vertical space. * See https://bugs.eclipse.org/bugs/show_bug.cgi?id=72489. * If the old behavior is desired by subclasses, get the returned composite's * layout data and set grabExcessVerticalSpace to true. */ @Override protected Control createDialogArea(Composite parent) { // Create a composite with standard margins and spacing // Add the messageArea to this composite so that as subclasses add widgets to the messageArea // and dialogArea, the number of children of parent remains fixed and with consistent layout. // Fixes bug #240135 Composite composite = new Composite(parent, SWT.NONE); createMessageArea(composite); createSupportArea(parent); GridLayout layout = new GridLayout(); layout.marginHeight = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN); layout.marginWidth = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_MARGIN); layout.verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING); layout.horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING); layout.numColumns = 2; composite.setLayout(layout); GridData childData = new GridData(GridData.FILL_BOTH); childData.horizontalSpan = 2; childData.grabExcessVerticalSpace = false; composite.setLayoutData(childData); composite.setFont(parent.getFont()); return composite; } @Override protected void createDialogAndButtonArea(Composite parent) { super.createDialogAndButtonArea(parent); if (this.dialogArea instanceof Composite) { // Create a label if there are no children to force a smaller layout Composite dialogComposite = (Composite) dialogArea; if (dialogComposite.getChildren().length == 0) { new Label(dialogComposite, SWT.NULL); } } } @Override protected Image getImage() { if (status != null) { if (status.getSeverity() == IStatus.WARNING) { return getWarningImage(); } if (status.getSeverity() == IStatus.INFO) { return getInfoImage(); } } // If it was not a warning or an error then return the error image return getErrorImage(); } /** * Create this dialog's drop-down list component. The list is displayed * after the user presses details button. It is developer responsibility * to display details button if and only if there is some content on * drop down list. The visibility of the details button is controlled by * {@link #shouldShowDetailsButton()}, which should also be overridden * together with this method. * * @param parent * the parent composite * @return the drop-down list component * @see #shouldShowDetailsButton() */ protected List createDropDownList(Composite parent) { // create the list list = new List(parent, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL | SWT.MULTI); // fill the list populateList(list); GridData data = new GridData(GridData.HORIZONTAL_ALIGN_FILL | GridData.GRAB_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL | GridData.GRAB_VERTICAL); data.heightHint = 150; data.horizontalSpan = 2; list.setLayoutData(data); list.setFont(parent.getFont()); Menu copyMenu = new Menu(list); MenuItem copyItem = new MenuItem(copyMenu, SWT.NONE); copyItem.addSelectionListener(new SelectionListener() { @Override public void widgetSelected(SelectionEvent e) { copyToClipboard(); } @Override public void widgetDefaultSelected(SelectionEvent e) { copyToClipboard(); } }); copyItem.setText(JFaceResources.getString("copy")); //$NON-NLS-1$ list.setMenu(copyMenu); listCreated = true; return list; } /** * Extends <code>Window.open()</code>. Opens an error dialog to display * the error. If you specified a mask to filter the displaying of these * children, the error dialog will only be displayed if there is at least * one child status matching the mask. */ @Override public int open() { if (!AUTOMATED_MODE && shouldDisplay(status, displayMask)) { return super.open(); } setReturnCode(OK); return OK; } /** * Opens an error dialog to display the given error. Use this method if the * error object being displayed does not contain child items, or if you wish * to display all such items without filtering. * * @param parent * the parent shell of the dialog, or <code>null</code> if none * @param dialogTitle * the title to use for this dialog, or <code>null</code> to * indicate that the default title should be used * @param message * the message to show in this dialog, or <code>null</code> to * indicate that the error's message should be shown as the * primary message * @param status * the error to show to the user * @return the code of the button that was pressed that resulted in this * dialog closing. This will be <code>Dialog.OK</code> if the OK * button was pressed, or <code>Dialog.CANCEL</code> if this * dialog's close window decoration or the ESC key was used. */ public static int openError(Shell parent, String dialogTitle, String message, IStatus status) { return openError(parent, dialogTitle, message, status, IStatus.OK | IStatus.INFO | IStatus.WARNING | IStatus.ERROR); } /** * Opens an error dialog to display the given error. Use this method if the * error object being displayed contains child items <it>and </it> you wish * to specify a mask which will be used to filter the displaying of these * children. The error dialog will only be displayed if there is at least * one child status matching the mask. * * @param parentShell * the parent shell of the dialog, or <code>null</code> if none * @param title * the title to use for this dialog, or <code>null</code> to * indicate that the default title should be used * @param message * the message to show in this dialog, or <code>null</code> to * indicate that the error's message should be shown as the * primary message * @param status * the error to show to the user * @param displayMask * the mask to use to filter the displaying of child items, as * per <code>IStatus.matches</code> * @return the code of the button that was pressed that resulted in this * dialog closing. This will be <code>Dialog.OK</code> if the OK * button was pressed, or <code>Dialog.CANCEL</code> if this * dialog's close window decoration or the ESC key was used. * @see org.eclipse.core.runtime.IStatus#matches(int) */ public static int openError(Shell parentShell, String title, String message, IStatus status, int displayMask) { ErrorDialog dialog = new ErrorDialog(parentShell, title, message, status, displayMask); return dialog.open(); } /** * Populates the list using this error dialog's status object. This walks * the child static of the status object and displays them in a list. The * format for each entry is status_path : status_message If the status's * path was null then it (and the colon) are omitted. * * @param listToPopulate * The list to fill. * * @see #listContentExists() */ private void populateList(List listToPopulate) { populateList(listToPopulate, status, 0, shouldIncludeTopLevelErrorInDetails); } /** * This method checks if any content will be placed on the list. * It mimics the behavior of {@link #populateList(List)}. * * @return true if {@link #populateList(List)} will add anything to a list * * @see #populateList(List) */ private boolean listContentExists() { return listContentExists(status, shouldIncludeTopLevelErrorInDetails); } /** * Populate the list with the messages from the given status. Traverse the * children of the status deeply and also traverse CoreExceptions that * appear in the status. * * @param listToPopulate * the list to populate * @param buildingStatus * the status being displayed * @param nesting * the nesting level (increases one level for each level of * children) * @param includeStatus * whether to include the buildingStatus in the display or just * its children */ private void populateList(List listToPopulate, IStatus buildingStatus, int nesting, boolean includeStatus) { if (!buildingStatus.matches(displayMask)) { return; } Throwable t = buildingStatus.getException(); boolean incrementNesting = false; if (includeStatus) { StringBuffer sb = new StringBuffer(); for (int i = 0; i < nesting; i++) { sb.append(NESTING_INDENT); } String message = buildingStatus.getMessage(); sb.append(message); java.util.List<String> lines = readLines(sb.toString()); for (Iterator<String> iterator = lines.iterator(); iterator.hasNext();) { String line = iterator.next(); listToPopulate.add(line); } incrementNesting = true; } if (!(t instanceof CoreException) && t != null) { // Include low-level exception message StringBuffer sb = new StringBuffer(); for (int i = 0; i < nesting; i++) { sb.append(NESTING_INDENT); } String message = t.getLocalizedMessage(); if (message == null) { message = t.toString(); } sb.append(message); listToPopulate.add(sb.toString()); incrementNesting = true; } if (incrementNesting) { nesting++; } // Look for a nested core exception if (t instanceof CoreException) { CoreException ce = (CoreException) t; IStatus eStatus = ce.getStatus(); // Only print the exception message if it is not contained in the // parent message if (message == null || message.indexOf(eStatus.getMessage()) == -1) { populateList(listToPopulate, eStatus, nesting, true); } } // Look for child status IStatus[] children = buildingStatus.getChildren(); for (int i = 0; i < children.length; i++) { populateList(listToPopulate, children[i], nesting, true); } } private static java.util.List<String> readLines(final String s) { java.util.List<String> lines = new ArrayList<>(); BufferedReader reader = new BufferedReader(new StringReader(s)); String line; try { while ((line = reader.readLine()) != null) { if (line.length() > 0) lines.add(line); } } catch (IOException e) { // shouldn't get this } return lines; } /** * This method checks if {@link #populateList(List, IStatus, int, boolean)} * will add anything to the list. * * @param buildingStatus * A status to be considered. * @param includeStatus * This flag indicates if top level status should be placed on a * list. * @return true if any new content will be added to the list. * @see #listContentExists(IStatus, boolean) */ private boolean listContentExists(IStatus buildingStatus, boolean includeStatus) { if (!buildingStatus.matches(displayMask)) { return false; } Throwable t = buildingStatus.getException(); if (includeStatus) { return true; } if (!(t instanceof CoreException) && t != null) { return true; } boolean result = false; // Look for a nested core exception if (t instanceof CoreException) { CoreException ce = (CoreException) t; IStatus eStatus = ce.getStatus(); // Gets exception message if it is not contained in the // parent message if (message == null || message.indexOf(eStatus.getMessage()) == -1) { result |= listContentExists(eStatus, true); } } // Look for child status IStatus[] children = buildingStatus.getChildren(); for (int i = 0; i < children.length; i++) { result |= listContentExists(children[i], true); } return result; } /** * Returns whether the given status object should be displayed. * * @param status * a status object * @param mask * a mask as per <code>IStatus.matches</code> * @return <code>true</code> if the given status should be displayed, and * <code>false</code> otherwise * @see org.eclipse.core.runtime.IStatus#matches(int) */ protected static boolean shouldDisplay(IStatus status, int mask) { IStatus[] children = status.getChildren(); if (children == null || children.length == 0) { return status.matches(mask); } for (int i = 0; i < children.length; i++) { if (children[i].matches(mask)) { return true; } } return false; } /** * Toggles the unfolding of the details area. This is triggered by the user * pressing the details button. */ private void toggleDetailsArea() { boolean opened = false; Point windowSize = getShell().getSize(); if (listCreated) { list.dispose(); listCreated = false; detailsButton.setText(IDialogConstants.SHOW_DETAILS_LABEL); opened = false; } else { list = createDropDownList((Composite) getContents()); detailsButton.setText(IDialogConstants.HIDE_DETAILS_LABEL); getContents().getShell().layout(); opened = true; } Point newSize = getShell().computeSize(SWT.DEFAULT, SWT.DEFAULT); int diffY = newSize.y - windowSize.y; // increase the dialog height if details were opened and such increase is necessary // decrease the dialog height if details were closed and empty space appeared if ((opened && diffY > 0) || (!opened && diffY < 0)) { getShell().setSize(new Point(windowSize.x, windowSize.y + (diffY))); } } /** * Put the details of the status of the error onto the stream. * * @param buildingStatus * @param buffer * @param nesting */ private void populateCopyBuffer(IStatus buildingStatus, StringBuffer buffer, int nesting) { if (!buildingStatus.matches(displayMask)) { return; } for (int i = 0; i < nesting; i++) { buffer.append(NESTING_INDENT); } buffer.append(buildingStatus.getMessage()); buffer.append("\n"); //$NON-NLS-1$ // Look for a nested core exception Throwable t = buildingStatus.getException(); if (t instanceof CoreException) { CoreException ce = (CoreException) t; populateCopyBuffer(ce.getStatus(), buffer, nesting + 1); } else if (t != null) { // Include low-level exception message for (int i = 0; i < nesting; i++) { buffer.append(NESTING_INDENT); } String message = t.getLocalizedMessage(); if (message == null) { message = t.toString(); } buffer.append(message); buffer.append("\n"); //$NON-NLS-1$ } IStatus[] children = buildingStatus.getChildren(); for (int i = 0; i < children.length; i++) { populateCopyBuffer(children[i], buffer, nesting + 1); } } /** * Copy the contents of the statuses to the clipboard. */ private void copyToClipboard() { if (clipboard != null) { clipboard.dispose(); } StringBuffer statusBuffer = new StringBuffer(); populateCopyBuffer(status, statusBuffer, 0); clipboard = new Clipboard(list.getDisplay()); clipboard.setContents(new Object[] { statusBuffer.toString() }, new Transfer[] { TextTransfer.getInstance() }); } @Override public boolean close() { if (clipboard != null) { clipboard.dispose(); } return super.close(); } /** * Show the details portion of the dialog if it is not already visible. This * method will only work when it is invoked after the control of the dialog * has been set. In other words, after the <code>createContents</code> * method has been invoked and has returned the control for the content area * of the dialog. Invoking the method before the content area has been set * or after the dialog has been disposed will have no effect. * * @since 3.1 */ protected final void showDetailsArea() { if (!listCreated) { Control control = getContents(); if (control != null && !control.isDisposed()) { toggleDetailsArea(); } } } /** * Return whether the Details button should be included. This method is * invoked once when the dialog is built. Default implementation is tight to * default implementation of {@link #createDropDownList(Composite)} and * displays details button if there is anything on the display list. * * @return whether the Details button should be included * @since 3.1 * @see #createDropDownList(Composite) */ protected boolean shouldShowDetailsButton() { return listContentExists(); } /** * Set the status displayed by this error dialog to the given status. This * only affects the status displayed by the Details list. The message, image * and title should be updated by the subclass, if desired. * * @param status * the status to be displayed in the details list * @since 3.1 */ protected final void setStatus(IStatus status) { if (this.status != status) { this.status = status; } shouldIncludeTopLevelErrorInDetails = true; if (listCreated) { repopulateList(); } } /** * Repopulate the supplied list widget. */ private void repopulateList() { if (list != null && !list.isDisposed()) { list.removeAll(); populateList(list); } } @Override int getColumnCount() { if (Policy.getErrorSupportProvider() == null) return 2; return 3; } @Override protected boolean isResizable() { return true; } }