org.eclipse.ui.editors/src/org/eclipse/ui/editors/text/DefaultEncodingSupport.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2018 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.editors.text;

 import java.io.CharConversionException;
 import java.io.UnsupportedEncodingException;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.BusyIndicator;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.swt.widgets.Shell;

 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences.IPreferenceChangeListener;
 import org.eclipse.core.runtime.preferences.InstanceScope;

 import org.eclipse.core.resources.ResourcesPlugin;

 import org.eclipse.jface.action.IAction;

 import org.eclipse.ui.IEditorInput;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.internal.editors.text.NLSUtility;

 import org.eclipse.ui.texteditor.IDocumentProvider;
 import org.eclipse.ui.texteditor.ITextEditorActionConstants;
 import org.eclipse.ui.texteditor.StatusTextEditor;
 import org.eclipse.ui.texteditor.TextEditorAction;


 /**
  * The standard implementation of <code>IEncodingSupport</code>.
  * @since 2.0
  */
 public class DefaultEncodingSupport implements IEncodingSupport {

 	/** Internal preference change listener. */
 	private IPreferenceChangeListener fPreferenceChangeListener;
 	/** The editor this support is associated with. */
 	private StatusTextEditor fTextEditor;

 	/**
 	 * Creates a new encoding support.
 	 */
 	public DefaultEncodingSupport() {
 		super();
 	}

 	/**
 	 * Associates this encoding support to the given text editor and initializes this encoding.
 	 *
 	 * @param textEditor the editor
 	 */
 	public void initialize(StatusTextEditor textEditor) {

 		fTextEditor= textEditor;

 		IEclipsePreferences prefs= InstanceScope.INSTANCE.getNode(ResourcesPlugin.PI_RESOURCES);

 		fPreferenceChangeListener= event -> {
 			if (ResourcesPlugin.PREF_ENCODING.equals(event.getKey())) {
 				// null means: use default
 				Runnable runnable= () -> setEncoding(null, false);
 				if (Display.getCurrent() != null)
 					runnable.run();
 				else {
 					// Post runnable into UI thread
 					Shell shell;
 					if (fTextEditor != null)
 						shell= fTextEditor.getSite().getShell();
 					else
 						shell= getActiveWorkbenchShell();
 					Display display;
 					if (shell != null)
 						display= shell.getDisplay();
 					else
 						display= Display.getDefault();
 					display.asyncExec(runnable);
 				}
 			}
 		};

 		prefs.addPreferenceChangeListener(fPreferenceChangeListener);
 	}

 	/**
 	 * Disposes this encoding support.
 	 */
 	public void dispose() {
 		IEclipsePreferences prefs= InstanceScope.INSTANCE.getNode(ResourcesPlugin.PI_RESOURCES);
 		prefs.removePreferenceChangeListener(fPreferenceChangeListener);
 		fTextEditor= null;
 	}

 	/**
 	 * Resets this encoding support. Should be called if, e.g., the input element of the
 	 * associated editor changed.
 	 */
 	public void reset() {
 	}

 	/**
 	 * Sets the encoding of the editor's input to the given value. If <code>overwrite</code> is
 	 * <code>true</code> the value is set even if the encoding is already set.
 	 *
 	 * @param encoding the new encoding
 	 * @param overwrite <code>true</code> if current encoding should be overwritten
 	 */
 	protected void setEncoding(String encoding, boolean overwrite) {
 		IDocumentProvider p= fTextEditor.getDocumentProvider();
 		if (p instanceof IStorageDocumentProvider) {
 			final IEditorInput input= fTextEditor.getEditorInput();
 			IStorageDocumentProvider provider= (IStorageDocumentProvider)p;
 			String current= provider.getEncoding(input);
 			if (!fTextEditor.isDirty()) {
 				String internal= encoding == null ? "" : encoding; //$NON-NLS-1$
 				boolean apply= (overwrite || current == null) && !internal.equals(current);
 				if (apply) {
 					provider.setEncoding(input, encoding);
 					Runnable encodingSetter=
 							() -> fTextEditor.doRevertToSaved();
 					Display display= fTextEditor.getSite().getShell().getDisplay();
 					if (display != null && !display.isDisposed())
 						BusyIndicator.showWhile(display, encodingSetter);
 					else
 						encodingSetter.run();
 				}
 			}
 		}
 	}

 	@Override
 	public void setEncoding(String encoding) {
 		setEncoding(encoding, true);
 	}

 	@Override
 	public String getEncoding() {
 		IDocumentProvider p= fTextEditor.getDocumentProvider();
 		if (p instanceof IStorageDocumentProvider) {
 			IStorageDocumentProvider provider= (IStorageDocumentProvider) p;
 			return provider.getEncoding(fTextEditor.getEditorInput());
 		}
 		return null;
 	}

 	@Override
 	public String getDefaultEncoding() {
 		IDocumentProvider p= fTextEditor.getDocumentProvider();
 		if (p instanceof IStorageDocumentProvider) {
 			IStorageDocumentProvider provider= (IStorageDocumentProvider) p;
 			return provider.getDefaultEncoding();
 		}
 		return null;
 	}

 	/**
 	 * Returns a status header for the given status.
 	 *
 	 * @param status the status
 	 * @return a status header for the given status.
 	 */
 	public String getStatusHeader(IStatus status) {
 		Throwable t= status.getException();

 		if (t instanceof CharConversionException)
 			return TextEditorMessages.Editor_error_unreadable_encoding_header;

 		if (t instanceof UnsupportedEncodingException)
 			return TextEditorMessages.Editor_error_unsupported_encoding_header;

 		return null;
 	}

 	/**
 	 * Returns a banner for the given status.
 	 *
 	 * @param status the status
 	 * @return a banner for the given status.
 	 */
 	public String getStatusBanner(IStatus status) {
 		Throwable t= status.getException();

 		if (t instanceof CharConversionException)
 			return TextEditorMessages.Editor_error_unreadable_encoding_banner;

 		if (t instanceof UnsupportedEncodingException)
 			return TextEditorMessages.Editor_error_unsupported_encoding_banner;

 		return null;

 	}

 	/**
 	 * Returns a status message if any.
 	 *
 	 * @param status the status
 	 * @return a status message indicating encoding problems or <code>null</code> otherwise
 	 */
 	public String getStatusMessage(IStatus status) {
 		Throwable t= status.getException();
 		if (t instanceof CharConversionException || t instanceof UnsupportedEncodingException) {

 			String encoding= getEncoding();
 			if (encoding == null)
 				encoding= getDefaultEncoding();

 			if (t instanceof CharConversionException) {
 				if (encoding != null)
 					return NLSUtility.format(TextEditorMessages.Editor_error_unreadable_encoding_message_arg, encoding);
 				return TextEditorMessages.Editor_error_unreadable_encoding_message;
 			}

 			if (t instanceof UnsupportedEncodingException) {
 				if (encoding != null)
 					return NLSUtility.format(TextEditorMessages.Editor_error_unsupported_encoding_message_arg, encoding);
 				return TextEditorMessages.Editor_error_unsupported_encoding_message;
 			}
 		}

 		return null;
 	}

 	/**
 	 * Returns <code>true</code> if the given status is an
 	 * encoding error.
 	 *
 	 * @param status the status to check
 	 * @return <code>true</code> if the given status is an encoding error
 	 * @since 3.1
 	 */
 	public boolean isEncodingError(IStatus status) {
 		if (status == null || status.getSeverity() != IStatus.ERROR)
 			return false;

 		Throwable t= status.getException();
 		return t instanceof CharConversionException || t instanceof UnsupportedEncodingException;
 	}

 	/**
 	 * Creates the control which allows to change the encoding.
 	 * In case of encoding errors this control will be placed below
 	 * the status of the status editor.
 	 *
 	 * @param parent the parent control
 	 * @param status the status
 	 * @since 3.1
 	 */
 	public void createStatusEncodingChangeControl(Composite parent, final IStatus status) {
 		final IAction action= fTextEditor.getAction(ITextEditorActionConstants.CHANGE_ENCODING);
 		if (action instanceof TextEditorAction)
 			((TextEditorAction)action).update();

 		if (action == null || !action.isEnabled())
 			return;

 		Shell shell= parent.getShell();
 		Display display= shell.getDisplay();
 		Color bgColor= display.getSystemColor(SWT.COLOR_LIST_BACKGROUND);

 		Button button= new Button(parent, SWT.PUSH | SWT.FLAT);
 		button.setText(action.getText());
 		button.addSelectionListener(new SelectionAdapter() {
 			/*
 			 * @see org.eclipse.swt.events.SelectionAdapter#widgetDefaultSelected(org.eclipse.swt.events.SelectionEvent)
 			 */
 			@Override
 			public void widgetSelected(SelectionEvent e) {
 				action.run();
 			}
 		});
 		button.setFocus();

 		Label filler= new Label(parent, SWT.NONE);
 		filler.setLayoutData(new GridData(GridData.FILL_BOTH));
 		filler.setBackground(bgColor);
 	}

 	/**
 	 * Returns the shell of the active workbench window.
 	 *
 	 * @return the shell of the active workbench window or <code>null</code> if none
 	 * @since 3.2
 	 */
 	private static Shell getActiveWorkbenchShell() {
 		 IWorkbenchWindow window= PlatformUI.getWorkbench().getActiveWorkbenchWindow();
 		 if (window != null)
 		 	return window.getShell();

 		 return null;
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2018 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.editors.text;

	import java.io.CharConversionException;
	import java.io.UnsupportedEncodingException;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.BusyIndicator;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.swt.widgets.Shell;

	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.preferences.IEclipsePreferences;
	import org.eclipse.core.runtime.preferences.IEclipsePreferences.IPreferenceChangeListener;
	import org.eclipse.core.runtime.preferences.InstanceScope;

	import org.eclipse.core.resources.ResourcesPlugin;

	import org.eclipse.jface.action.IAction;

	import org.eclipse.ui.IEditorInput;
	import org.eclipse.ui.IWorkbenchWindow;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.internal.editors.text.NLSUtility;

	import org.eclipse.ui.texteditor.IDocumentProvider;
	import org.eclipse.ui.texteditor.ITextEditorActionConstants;
	import org.eclipse.ui.texteditor.StatusTextEditor;
	import org.eclipse.ui.texteditor.TextEditorAction;


	/**
	* The standard implementation of <code>IEncodingSupport</code>.
	* @since 2.0
	*/
	public class DefaultEncodingSupport implements IEncodingSupport {

	/** Internal preference change listener. */
	private IPreferenceChangeListener fPreferenceChangeListener;
	/** The editor this support is associated with. */
	private StatusTextEditor fTextEditor;

	/**
	* Creates a new encoding support.
	*/
	public DefaultEncodingSupport() {
	super();
	}

	/**
	* Associates this encoding support to the given text editor and initializes this encoding.
	*
	* @param textEditor the editor
	*/
	public void initialize(StatusTextEditor textEditor) {

	fTextEditor= textEditor;

	IEclipsePreferences prefs= InstanceScope.INSTANCE.getNode(ResourcesPlugin.PI_RESOURCES);

	fPreferenceChangeListener= event -> {
	if (ResourcesPlugin.PREF_ENCODING.equals(event.getKey())) {
	// null means: use default
	Runnable runnable= () -> setEncoding(null, false);
	if (Display.getCurrent() != null)
	runnable.run();
	else {
	// Post runnable into UI thread
	Shell shell;
	if (fTextEditor != null)
	shell= fTextEditor.getSite().getShell();
	else
	shell= getActiveWorkbenchShell();
	Display display;
	if (shell != null)
	display= shell.getDisplay();
	else
	display= Display.getDefault();
	display.asyncExec(runnable);
	}
	}
	};

	prefs.addPreferenceChangeListener(fPreferenceChangeListener);
	}

	/**
	* Disposes this encoding support.
	*/
	public void dispose() {
	IEclipsePreferences prefs= InstanceScope.INSTANCE.getNode(ResourcesPlugin.PI_RESOURCES);
	prefs.removePreferenceChangeListener(fPreferenceChangeListener);
	fTextEditor= null;
	}

	/**
	* Resets this encoding support. Should be called if, e.g., the input element of the
	* associated editor changed.
	*/
	public void reset() {
	}

	/**
	* Sets the encoding of the editor's input to the given value. If <code>overwrite</code> is
	* <code>true</code> the value is set even if the encoding is already set.
	*
	* @param encoding the new encoding
	* @param overwrite <code>true</code> if current encoding should be overwritten
	*/
	protected void setEncoding(String encoding, boolean overwrite) {
	IDocumentProvider p= fTextEditor.getDocumentProvider();
	if (p instanceof IStorageDocumentProvider) {
	final IEditorInput input= fTextEditor.getEditorInput();
	IStorageDocumentProvider provider= (IStorageDocumentProvider)p;
	String current= provider.getEncoding(input);
	if (!fTextEditor.isDirty()) {
	String internal= encoding == null ? "" : encoding; //$NON-NLS-1$
	boolean apply= (overwrite \|\| current == null) && !internal.equals(current);
	if (apply) {
	provider.setEncoding(input, encoding);
	Runnable encodingSetter=
	() -> fTextEditor.doRevertToSaved();
	Display display= fTextEditor.getSite().getShell().getDisplay();
	if (display != null && !display.isDisposed())
	BusyIndicator.showWhile(display, encodingSetter);
	else
	encodingSetter.run();
	}
	}
	}
	}

	@Override
	public void setEncoding(String encoding) {
	setEncoding(encoding, true);
	}

	@Override
	public String getEncoding() {
	IDocumentProvider p= fTextEditor.getDocumentProvider();
	if (p instanceof IStorageDocumentProvider) {
	IStorageDocumentProvider provider= (IStorageDocumentProvider) p;
	return provider.getEncoding(fTextEditor.getEditorInput());
	}
	return null;
	}

	@Override
	public String getDefaultEncoding() {
	IDocumentProvider p= fTextEditor.getDocumentProvider();
	if (p instanceof IStorageDocumentProvider) {
	IStorageDocumentProvider provider= (IStorageDocumentProvider) p;
	return provider.getDefaultEncoding();
	}
	return null;
	}

	/**
	* Returns a status header for the given status.
	*
	* @param status the status
	* @return a status header for the given status.
	*/
	public String getStatusHeader(IStatus status) {
	Throwable t= status.getException();

	if (t instanceof CharConversionException)
	return TextEditorMessages.Editor_error_unreadable_encoding_header;

	if (t instanceof UnsupportedEncodingException)
	return TextEditorMessages.Editor_error_unsupported_encoding_header;

	return null;
	}

	/**
	* Returns a banner for the given status.
	*
	* @param status the status
	* @return a banner for the given status.
	*/
	public String getStatusBanner(IStatus status) {
	Throwable t= status.getException();

	if (t instanceof CharConversionException)
	return TextEditorMessages.Editor_error_unreadable_encoding_banner;

	if (t instanceof UnsupportedEncodingException)
	return TextEditorMessages.Editor_error_unsupported_encoding_banner;

	return null;

	}

	/**
	* Returns a status message if any.
	*
	* @param status the status
	* @return a status message indicating encoding problems or <code>null</code> otherwise
	*/
	public String getStatusMessage(IStatus status) {
	Throwable t= status.getException();
	if (t instanceof CharConversionException \|\| t instanceof UnsupportedEncodingException) {

	String encoding= getEncoding();
	if (encoding == null)
	encoding= getDefaultEncoding();

	if (t instanceof CharConversionException) {
	if (encoding != null)
	return NLSUtility.format(TextEditorMessages.Editor_error_unreadable_encoding_message_arg, encoding);
	return TextEditorMessages.Editor_error_unreadable_encoding_message;
	}

	if (t instanceof UnsupportedEncodingException) {
	if (encoding != null)
	return NLSUtility.format(TextEditorMessages.Editor_error_unsupported_encoding_message_arg, encoding);
	return TextEditorMessages.Editor_error_unsupported_encoding_message;
	}
	}

	return null;
	}

	/**
	* Returns <code>true</code> if the given status is an
	* encoding error.
	*
	* @param status the status to check
	* @return <code>true</code> if the given status is an encoding error
	* @since 3.1
	*/
	public boolean isEncodingError(IStatus status) {
	if (status == null \|\| status.getSeverity() != IStatus.ERROR)
	return false;

	Throwable t= status.getException();
	return t instanceof CharConversionException \|\| t instanceof UnsupportedEncodingException;
	}

	/**
	* Creates the control which allows to change the encoding.
	* In case of encoding errors this control will be placed below
	* the status of the status editor.
	*
	* @param parent the parent control
	* @param status the status
	* @since 3.1
	*/
	public void createStatusEncodingChangeControl(Composite parent, final IStatus status) {
	final IAction action= fTextEditor.getAction(ITextEditorActionConstants.CHANGE_ENCODING);
	if (action instanceof TextEditorAction)
	((TextEditorAction)action).update();

	if (action == null \|\| !action.isEnabled())
	return;

	Shell shell= parent.getShell();
	Display display= shell.getDisplay();
	Color bgColor= display.getSystemColor(SWT.COLOR_LIST_BACKGROUND);

	Button button= new Button(parent, SWT.PUSH \| SWT.FLAT);
	button.setText(action.getText());
	button.addSelectionListener(new SelectionAdapter() {
	/*
	* @see org.eclipse.swt.events.SelectionAdapter#widgetDefaultSelected(org.eclipse.swt.events.SelectionEvent)
	*/
	@Override
	public void widgetSelected(SelectionEvent e) {
	action.run();
	}
	});
	button.setFocus();

	Label filler= new Label(parent, SWT.NONE);
	filler.setLayoutData(new GridData(GridData.FILL_BOTH));
	filler.setBackground(bgColor);
	}

	/**
	* Returns the shell of the active workbench window.
	*
	* @return the shell of the active workbench window or <code>null</code> if none
	* @since 3.2
	*/
	private static Shell getActiveWorkbenchShell() {
	IWorkbenchWindow window= PlatformUI.getWorkbench().getActiveWorkbenchWindow();
	if (window != null)
	return window.getShell();

	return null;
	}

	}