Java tutorial
/******************************************************************************* * Copyright (c) 2004, 2014 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 implementation *******************************************************************************/ package org.eclipse.jdt.internal.debug.ui.actions; import org.eclipse.core.commands.AbstractHandler; import org.eclipse.core.commands.ExecutionEvent; import org.eclipse.core.commands.IHandler; import org.eclipse.debug.core.DebugException; import org.eclipse.debug.core.model.IValue; import org.eclipse.debug.internal.ui.SWTFactory; import org.eclipse.jdt.debug.core.IJavaVariable; import org.eclipse.jdt.internal.debug.core.model.JDINullValue; import org.eclipse.jdt.internal.debug.ui.IJavaDebugHelpContextIds; import org.eclipse.jdt.internal.debug.ui.JDIDebugUIPlugin; import org.eclipse.jdt.internal.debug.ui.JDISourceViewer; import org.eclipse.jdt.internal.debug.ui.contentassist.CurrentFrameContext; import org.eclipse.jdt.internal.debug.ui.contentassist.JavaDebugContentAssistProcessor; import org.eclipse.jdt.internal.debug.ui.display.DisplayViewerConfiguration; import org.eclipse.jdt.ui.text.IJavaPartitions; import org.eclipse.jdt.ui.text.JavaTextTools; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.dialogs.IDialogSettings; import org.eclipse.jface.dialogs.TrayDialog; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.text.Document; import org.eclipse.jface.text.DocumentEvent; import org.eclipse.jface.text.IDocument; import org.eclipse.jface.text.IDocumentListener; import org.eclipse.jface.text.ITextOperationTarget; import org.eclipse.jface.text.IUndoManager; import org.eclipse.jface.text.TextViewer; import org.eclipse.jface.text.TextViewerUndoManager; import org.eclipse.jface.text.contentassist.IContentAssistProcessor; import org.eclipse.jface.text.source.ISourceViewer; import org.eclipse.osgi.util.NLS; import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; import org.eclipse.ui.IWorkbench; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.handlers.IHandlerActivation; import org.eclipse.ui.handlers.IHandlerService; import org.eclipse.ui.texteditor.ITextEditorActionDefinitionIds; /** * A dialog which prompts the user to enter an expression for * evaluation. */ public class ExpressionInputDialog extends TrayDialog { protected IJavaVariable fVariable; protected String fResult = null; // Input area composite which acts as a placeholder for // input widgetry that is created/disposed dynamically. protected Composite fInputArea; // Source viewer widgets protected Composite fSourceViewerComposite; protected JDISourceViewer fSourceViewer; protected IContentAssistProcessor fCompletionProcessor; protected IDocumentListener fDocumentListener; protected IHandlerService fService; protected IHandlerActivation fActivation; // protected HandlerSubmission fSubmission; // Text for error reporting protected Text fErrorText; /** * @param parentShell the shell to create the dialog in * @param variable the variable being edited */ protected ExpressionInputDialog(Shell parentShell, IJavaVariable variable) { super(parentShell); setShellStyle(SWT.CLOSE | SWT.MIN | SWT.MAX | SWT.RESIZE); fVariable = variable; } /* (non-Javadoc) * @see org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets.Composite) */ @Override protected Control createDialogArea(Composite parent) { IWorkbench workbench = PlatformUI.getWorkbench(); workbench.getHelpSystem().setHelp(parent, IJavaDebugHelpContextIds.EXPRESSION_INPUT_DIALOG); Composite composite = (Composite) super.createDialogArea(parent); // Create the composite which will hold the input widgetry fInputArea = createInputArea(composite); // Create the error reporting text area fErrorText = createErrorText(composite); // Create the source viewer after creating the error text so that any // necessary error messages can be set. populateInputArea(fInputArea); return composite; } /** * Returns the text widget for reporting errors * @param parent parent composite * @return the error text widget */ protected Text createErrorText(Composite parent) { Text text = SWTFactory.createText(parent, SWT.READ_ONLY, 1, ""); //$NON-NLS-1$ text.setBackground(text.getDisplay().getSystemColor(SWT.COLOR_WIDGET_BACKGROUND)); return text; } /** * Returns the composite that will be used to contain the * input widgetry. * @param composite the parent composite * @return the composite that will contain the input widgets */ protected Composite createInputArea(Composite parent) { Composite composite = SWTFactory.createComposite(parent, parent.getFont(), 1, 1, GridData.FILL_BOTH, 0, 0); Dialog.applyDialogFont(composite); return composite; } /** * Creates the appropriate widgetry in the input area. This * method is intended to be overridden by subclasses who wish * to use alternate input widgets. * @param parent parent composite */ protected void populateInputArea(Composite parent) { fSourceViewerComposite = SWTFactory.createComposite(parent, parent.getFont(), 1, 1, GridData.FILL_BOTH, 0, 0); String name = ActionMessages.ExpressionInputDialog_3; try { name = fVariable.getName(); } catch (DebugException e) { JDIDebugUIPlugin.log(e); } SWTFactory.createWrapLabel(fSourceViewerComposite, NLS.bind(ActionMessages.ExpressionInputDialog_0, new String[] { name }), 1, convertHorizontalDLUsToPixels(IDialogConstants.MINIMUM_MESSAGE_AREA_WIDTH)); fSourceViewer = new JDISourceViewer(fSourceViewerComposite, null, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL); fSourceViewer.setInput(fSourceViewerComposite); configureSourceViewer(); fSourceViewer.doOperation(ITextOperationTarget.SELECT_ALL); } /** * Sets the visibility of the source viewer and the exclude attribute of its layout. * @param value If <code>true</code>, the viewer will be visible, if <code>false</code>, the viewer will be hidden. */ protected void setSourceViewerVisible(boolean value) { if (fSourceViewerComposite != null) { fSourceViewerComposite.setVisible(value); GridData data = (GridData) fSourceViewerComposite.getLayoutData(); data.exclude = !value; if (value) { fSourceViewer.getDocument().addDocumentListener(fDocumentListener); activateHandler(); } else if (fActivation != null) { fSourceViewer.getDocument().removeDocumentListener(fDocumentListener); fService.deactivateHandler(fActivation); } } } /** * Initializes the source viewer. This method is based on code in BreakpointConditionEditor. */ private void configureSourceViewer() { JavaTextTools tools = JDIDebugUIPlugin.getDefault().getJavaTextTools(); IDocument document = new Document(); tools.setupJavaDocumentPartitioner(document, IJavaPartitions.JAVA_PARTITIONING); fSourceViewer.configure(new DisplayViewerConfiguration() { @Override public IContentAssistProcessor getContentAssistantProcessor() { return getCompletionProcessor(); } }); fSourceViewer.setEditable(true); fSourceViewer.setDocument(document); final IUndoManager undoManager = new TextViewerUndoManager(10); fSourceViewer.setUndoManager(undoManager); undoManager.connect(fSourceViewer); fSourceViewer.getTextWidget().setFont(JFaceResources.getTextFont()); Control control = fSourceViewer.getControl(); GridData gd = new GridData(GridData.FILL_BOTH); control.setLayoutData(gd); gd = (GridData) fSourceViewer.getControl().getLayoutData(); gd.heightHint = convertHeightInCharsToPixels(10); gd.widthHint = convertWidthInCharsToPixels(40); document.set(getInitialText(fVariable)); fDocumentListener = new IDocumentListener() { public void documentAboutToBeChanged(DocumentEvent event) { } public void documentChanged(DocumentEvent event) { refreshValidState(fSourceViewer); } }; fSourceViewer.getDocument().addDocumentListener(fDocumentListener); activateHandler(); } /** * Activates the content assist handler. */ private void activateHandler() { IHandler handler = new AbstractHandler() { public Object execute(ExecutionEvent event) throws org.eclipse.core.commands.ExecutionException { fSourceViewer.doOperation(ISourceViewer.CONTENTASSIST_PROPOSALS); return null; } }; IWorkbench workbench = PlatformUI.getWorkbench(); fService = (IHandlerService) workbench.getAdapter(IHandlerService.class); fActivation = fService.activateHandler(ITextEditorActionDefinitionIds.CONTENT_ASSIST_PROPOSALS, handler); } /** * Returns the text that should be shown in the source viewer upon * initialization. The text should be presented in such a way that * it can be used as an evaluation expression which will return the * current value. * @param variable the variable * @return the initial text to display in the source viewer or <code>null</code> * if none. */ protected String getInitialText(IJavaVariable variable) { try { String signature = variable.getSignature(); if (signature.equals("Ljava/lang/String;")) { //$NON-NLS-1$ IValue value = variable.getValue(); if (!(value instanceof JDINullValue)) { String currentValue = value.getValueString(); StringBuffer buffer = new StringBuffer(currentValue.length()); buffer.append('"'); // Surround value in quotes char[] chars = currentValue.toCharArray(); for (int i = 0; i < chars.length; i++) { char c = chars[i]; if (c == '\b') { buffer.append("\\b"); //$NON-NLS-1$ } else if (c == '\t') { buffer.append("\\t"); //$NON-NLS-1$ } else if (c == '\n') { buffer.append("\\n"); //$NON-NLS-1$ } else if (c == '\f') { buffer.append("\\f"); //$NON-NLS-1$ } else if (c == '\r') { buffer.append("\\r"); //$NON-NLS-1$ } else if (c == '"') { buffer.append("\\\""); //$NON-NLS-1$ } else if (c == '\'') { buffer.append("\\\'"); //$NON-NLS-1$ } else if (c == '\\') { buffer.append("\\\\"); //$NON-NLS-1$ } else { buffer.append(c); } } buffer.append('"'); // Surround value in quotes return buffer.toString(); } } } catch (DebugException e) { } return null; } /** * Return the completion processor associated with this viewer. * @return DisplayConditionCompletionProcessor */ protected IContentAssistProcessor getCompletionProcessor() { if (fCompletionProcessor == null) { fCompletionProcessor = new JavaDebugContentAssistProcessor(new CurrentFrameContext()); } return fCompletionProcessor; } /** * @see org.eclipse.jface.preference.FieldEditor#refreshValidState() */ protected void refreshValidState(TextViewer viewer) { String errorMessage = null; if (viewer != null) { String text = viewer.getDocument().get(); boolean valid = text != null && text.trim().length() > 0; if (!valid) { errorMessage = ActionMessages.ExpressionInputDialog_1; } } setErrorMessage(errorMessage); } protected void refreshValidState() { refreshValidState(fSourceViewer); } /** * Sets the error message to display to the user. <code>null</code> * is the same as the empty string. * @param message the error message to display to the user or * <code>null</code> if the error message should be cleared */ protected void setErrorMessage(String message) { if (message == null) { message = ""; //$NON-NLS-1$ } fErrorText.setText(message); getButton(IDialogConstants.OK_ID).setEnabled(message.length() == 0); } /** * Persist the dialog size and store the user's input on OK is pressed. */ @Override protected void okPressed() { fResult = getText(); super.okPressed(); } /** * Returns the text that is currently displayed in the source viewer. * @return the text that is currently displayed in the source viewer */ protected String getText() { return fSourceViewer.getDocument().get(); } /** * Returns the text entered by the user or <code>null</code> if the user cancelled. * * @return the text entered by the user or <code>null</code> if the user cancelled */ public String getResult() { return fResult; } /** * Initializes the dialog shell with a title. */ @Override protected void configureShell(Shell newShell) { super.configureShell(newShell); newShell.setText(ActionMessages.ExpressionInputDialog_2); } /** * Override method to initialize the enablement of the OK button after * it is created. */ @Override protected void createButtonsForButtonBar(Composite parent) { super.createButtonsForButtonBar(parent); //do this here because setting the text will set enablement on the ok // button refreshValidState(); } /* (non-Javadoc) * @see org.eclipse.jface.window.Window#close() */ @Override public boolean close() { if (fActivation != null) { fService.deactivateHandler(fActivation); } if (fSourceViewer != null) { fSourceViewer.getDocument().removeDocumentListener(fDocumentListener); fSourceViewer.dispose(); fSourceViewer = null; } if (fSourceViewerComposite != null) { fSourceViewerComposite.dispose(); fSourceViewerComposite = null; } fDocumentListener = null; fCompletionProcessor = null; return super.close(); } /* (non-Javadoc) * @see org.eclipse.jface.dialogs.Dialog#getDialogBoundsSettings() */ @Override protected IDialogSettings getDialogBoundsSettings() { IDialogSettings settings = JDIDebugUIPlugin.getDefault().getDialogSettings(); IDialogSettings section = settings.getSection(getDialogSettingsSectionName()); if (section == null) { section = settings.addNewSection(getDialogSettingsSectionName()); } return section; } /** * @return the name to use to save the dialog settings */ protected String getDialogSettingsSectionName() { return "EXPRESSION_INPUT_DIALOG"; //$NON-NLS-1$ } }