bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/dialogs/AbstractEncodingFieldEditor.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.ide.dialogs;

 import java.nio.charset.Charset;
 import java.nio.charset.IllegalCharsetNameException;
 import java.util.List;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.ModifyEvent;
 import org.eclipse.swt.events.ModifyListener;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Group;

 import org.eclipse.jface.preference.FieldEditor;
 import org.eclipse.jface.preference.IPreferenceStore;

 import org.eclipse.ui.WorkbenchEncoding;
 import org.eclipse.ui.ide.IDEEncoding;

 import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;

 /**
  * The abstract superclass of editors used to set an
  * enconding. Any user entered
  * encodings will be added to the list of encodings in the
  * IDEEncoding.
  * @since 3.1
  * @see org.eclipse.ui.ide.IDEEncoding
  */
 public abstract class AbstractEncodingFieldEditor extends FieldEditor {
 	private Composite container;

 	private Button defaultEncodingButton;

 	private String defaultEnc;

 	private Button otherEncodingButton;

 	private Combo encodingCombo;

 	private boolean isValid = true;

 	private String oldSelectedEncoding;

 	/**
 	 * Create an instance of the receiver with no parameters
 	 * set.
 	 */
 	public AbstractEncodingFieldEditor() {
 		super();
 	}

 	/**
 	 * Create a new instance of the receiver on the preference called name
 	 * with a label of labelText.
 	 * @param name
 	 * @param labelText
 	 * @param parent
 	 */
 	public AbstractEncodingFieldEditor(String name, String labelText, Composite parent) {
 		super(name, labelText, parent);
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#adjustForNumColumns(int)
 	 */
 	protected void adjustForNumColumns(int numColumns) {
 		((GridData) getContainer().getLayoutData()).horizontalSpan = numColumns;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#doFillIntoGrid(org.eclipse.swt.widgets.Composite, int)
 	 */
 	protected void doFillIntoGrid(Composite parent, int numColumns) {
 		container = createEncodingGroup(parent, numColumns);
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#doLoad()
 	 */
 	protected void doLoad() {
 		if (encodingCombo != null) {
 			List encodings = IDEEncoding.getIDEEncodings();
 			String resourcePreference = getStoredValue();
 			populateEncodingsCombo(encodings, resourcePreference);
 			updateEncodingState(resourcePreference == null || resourcePreference.equals(defaultEnc));
 		}
 	}

 	/**
 	 * Get the value that is current stored for the encoding.
 	 * @return String
 	 */
 	protected abstract String getStoredValue();

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#doLoadDefault()
 	 */
 	protected void doLoadDefault() {
 		updateEncodingState(true);
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#getNumberOfControls()
 	 */
 	public int getNumberOfControls() {
 		return 1;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#isValid()
 	 */
 	public boolean isValid() {
 		return isValid;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#refreshValidState()
 	 */
 	protected void refreshValidState() {
 		updateValidState();
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.FieldEditor#setPreferenceStore(org.eclipse.jface.preference.IPreferenceStore)
 	 */
 	public void setPreferenceStore(IPreferenceStore store) {
 		super.setPreferenceStore(store);
 		defaultEnc = store.getDefaultString(getPreferenceName());
 		updateDefaultEncoding();
 	}

 	private void updateDefaultEncoding() {
 		defaultEncodingButton.setText(defaultButtonText()); //$NON-NLS-1$
 	}

 	private Composite getContainer() {
 		return container;
 	}

 	/**
 	 * Create the Groupd will all of the controls.
 	 * @param parent the parent widget
 	 * @param numColumns the number of columns in the parent
 	 * @return Group
 	 */
 	protected Group createEncodingGroup(Composite parent, int numColumns) {

 		Font font = parent.getFont();
 		Group group = new Group(parent, SWT.NONE);
 		GridData data = new GridData(GridData.FILL_HORIZONTAL);
 		group.setLayoutData(data);
 		GridLayout layout = new GridLayout();
 		layout.numColumns = 2;
 		group.setLayout(layout);
 		group.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.encoding")); //$NON-NLS-1$
 		group.setFont(font);

 		SelectionAdapter buttonListener = new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				updateEncodingState(defaultEncodingButton.getSelection());
 				updateValidState();
 			}
 		};

 		defaultEncodingButton = new Button(group, SWT.RADIO);
 		defaultEnc = findDefaultEncoding();
 		defaultEncodingButton.setText(defaultButtonText());
 		data = new GridData();
 		data.horizontalSpan = 2;
 		defaultEncodingButton.setLayoutData(data);
 		defaultEncodingButton.addSelectionListener(buttonListener);
 		defaultEncodingButton.setFont(font);

 		otherEncodingButton = new Button(group, SWT.RADIO);
 		otherEncodingButton.setText(IDEWorkbenchMessages
 				.getString("WorkbenchPreference.otherEncoding")); //$NON-NLS-1$
 		otherEncodingButton.addSelectionListener(buttonListener);
 		otherEncodingButton.setFont(font);

 		encodingCombo = new Combo(group, SWT.NONE);
 		data = new GridData();
 		encodingCombo.setFont(font);
 		encodingCombo.setLayoutData(data);
 		encodingCombo.addModifyListener(new ModifyListener() {
 			public void modifyText(ModifyEvent e) {
 				updateValidState();
 			}
 		});

 		return group;
 	}

 	/**
 	 * Get the default encoding for the object being shown.
 	 * @return String
 	 */
 	protected String findDefaultEncoding() {
 		return WorkbenchEncoding.getWorkbenchDefaultEncoding();
 	}

 	/**
 	 * Return the text for the default encoding button.
 	 * @return String
 	 */
 	protected String defaultButtonText() {
 		return IDEWorkbenchMessages.format(
 				"WorkbenchPreference.defaultEncoding", new String[] { defaultEnc });//$NON-NLS-1$
 	}

 	/**
 	 * Populate the encodings combo. Set the text based on the
 	 * selectedEncoding. If selectedEncoding is null set it to the
 	 * default.
 	 * @param encodings
 	 * @param selectedEncoding
 	 */
 	private void populateEncodingsCombo(List encodings, String selectedEncoding) {
 		String[] encodingStrings = new String[encodings.size()];
 		encodings.toArray(encodingStrings);
 		encodingCombo.setItems(encodingStrings);

 		if (selectedEncoding == null)
 			encodingCombo.setText(getDefaultEnc());
 		else
 			encodingCombo.setText(selectedEncoding);
 	}

 	private void updateEncodingState(boolean useDefault) {
 		defaultEncodingButton.setSelection(useDefault);
 		otherEncodingButton.setSelection(!useDefault);
 		encodingCombo.setEnabled(!useDefault);
 		updateValidState();
 	}

 	private void updateValidState() {
 		boolean isValidNow = isEncodingValid();
 		if (isValidNow != isValid) {
 			isValid = isValidNow;
 			if (isValid) {
 				clearErrorMessage();
 			} else {
 				showErrorMessage(IDEWorkbenchMessages
 						.getString("WorkbenchPreference.unsupportedEncoding")); //$NON-NLS-1$
 			}
 			fireStateChanged(IS_VALID, !isValid, isValid);

 			String newValue = getSelectedEncoding();
 			if (isValid && !newValue.equals(oldSelectedEncoding)) {
 				fireValueChanged(VALUE, oldSelectedEncoding, newValue);
 				oldSelectedEncoding = newValue;
 			}
 		}
 	}

 	/**
 	 * Get the encoding current selected.
 	 * @return String
 	 */
 	protected String getSelectedEncoding() {
 		if (defaultEncodingButton.getSelection()) {
 			return defaultEnc;
 		}
 		return encodingCombo.getText();
 	}

 	private boolean isEncodingValid() {
 		return defaultEncodingButton.getSelection() || isValidEncoding(encodingCombo.getText());
 	}

 	/**
 	 * Return whether or not this is a valid encoding.
 	 * @param enc
 	 * @return boolean
 	 */
 	private boolean isValidEncoding(String enc) {
 		try {
 			return Charset.isSupported(enc);
 		} catch (IllegalCharsetNameException e) {
 			//This is a valid exception
 			return false;
 		}

 	}

 	/**
 	 * Return the default encoding.
 	 * @return String
 	 */
 	protected String getDefaultEnc() {
 		return defaultEnc;
 	}

 	/**
 	 * Return whether or not the encoding setting changed.
 	 * @param encodingSetting the setting from the page.
 	 * @return boolean <code>true</code> if the resource encoding
 	 * is the same as before.
 	 */
 	protected boolean hasSameEncoding(String encodingSetting) {

 		String current = getStoredValue();

 		if (encodingSetting == null) {
 			//Changed if default is selected and there is no setting
 			return current == null || current.length() == 0;
 		}
 		return encodingSetting.equals(current);
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2004 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ui.ide.dialogs;

	import java.nio.charset.Charset;
	import java.nio.charset.IllegalCharsetNameException;
	import java.util.List;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.ModifyEvent;
	import org.eclipse.swt.events.ModifyListener;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Font;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Combo;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Group;

	import org.eclipse.jface.preference.FieldEditor;
	import org.eclipse.jface.preference.IPreferenceStore;

	import org.eclipse.ui.WorkbenchEncoding;
	import org.eclipse.ui.ide.IDEEncoding;

	import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;

	/**
	* The abstract superclass of editors used to set an
	* enconding. Any user entered
	* encodings will be added to the list of encodings in the
	* IDEEncoding.
	* @since 3.1
	* @see org.eclipse.ui.ide.IDEEncoding
	*/
	public abstract class AbstractEncodingFieldEditor extends FieldEditor {
	private Composite container;

	private Button defaultEncodingButton;

	private String defaultEnc;

	private Button otherEncodingButton;

	private Combo encodingCombo;

	private boolean isValid = true;

	private String oldSelectedEncoding;

	/**
	* Create an instance of the receiver with no parameters
	* set.
	*/
	public AbstractEncodingFieldEditor() {
	super();
	}

	/**
	* Create a new instance of the receiver on the preference called name
	* with a label of labelText.
	* @param name
	* @param labelText
	* @param parent
	*/
	public AbstractEncodingFieldEditor(String name, String labelText, Composite parent) {
	super(name, labelText, parent);
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#adjustForNumColumns(int)
	*/
	protected void adjustForNumColumns(int numColumns) {
	((GridData) getContainer().getLayoutData()).horizontalSpan = numColumns;
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#doFillIntoGrid(org.eclipse.swt.widgets.Composite, int)
	*/
	protected void doFillIntoGrid(Composite parent, int numColumns) {
	container = createEncodingGroup(parent, numColumns);
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#doLoad()
	*/
	protected void doLoad() {
	if (encodingCombo != null) {
	List encodings = IDEEncoding.getIDEEncodings();
	String resourcePreference = getStoredValue();
	populateEncodingsCombo(encodings, resourcePreference);
	updateEncodingState(resourcePreference == null \|\| resourcePreference.equals(defaultEnc));
	}
	}

	/**
	* Get the value that is current stored for the encoding.
	* @return String
	*/
	protected abstract String getStoredValue();

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#doLoadDefault()
	*/
	protected void doLoadDefault() {
	updateEncodingState(true);
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#getNumberOfControls()
	*/
	public int getNumberOfControls() {
	return 1;
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#isValid()
	*/
	public boolean isValid() {
	return isValid;
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#refreshValidState()
	*/
	protected void refreshValidState() {
	updateValidState();
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.FieldEditor#setPreferenceStore(org.eclipse.jface.preference.IPreferenceStore)
	*/
	public void setPreferenceStore(IPreferenceStore store) {
	super.setPreferenceStore(store);
	defaultEnc = store.getDefaultString(getPreferenceName());
	updateDefaultEncoding();
	}

	private void updateDefaultEncoding() {
	defaultEncodingButton.setText(defaultButtonText()); //$NON-NLS-1$
	}

	private Composite getContainer() {
	return container;
	}

	/**
	* Create the Groupd will all of the controls.
	* @param parent the parent widget
	* @param numColumns the number of columns in the parent
	* @return Group
	*/
	protected Group createEncodingGroup(Composite parent, int numColumns) {

	Font font = parent.getFont();
	Group group = new Group(parent, SWT.NONE);
	GridData data = new GridData(GridData.FILL_HORIZONTAL);
	group.setLayoutData(data);
	GridLayout layout = new GridLayout();
	layout.numColumns = 2;
	group.setLayout(layout);
	group.setText(IDEWorkbenchMessages.getString("WorkbenchPreference.encoding")); //$NON-NLS-1$
	group.setFont(font);

	SelectionAdapter buttonListener = new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	updateEncodingState(defaultEncodingButton.getSelection());
	updateValidState();
	}
	};

	defaultEncodingButton = new Button(group, SWT.RADIO);
	defaultEnc = findDefaultEncoding();
	defaultEncodingButton.setText(defaultButtonText());
	data = new GridData();
	data.horizontalSpan = 2;
	defaultEncodingButton.setLayoutData(data);
	defaultEncodingButton.addSelectionListener(buttonListener);
	defaultEncodingButton.setFont(font);

	otherEncodingButton = new Button(group, SWT.RADIO);
	otherEncodingButton.setText(IDEWorkbenchMessages
	.getString("WorkbenchPreference.otherEncoding")); //$NON-NLS-1$
	otherEncodingButton.addSelectionListener(buttonListener);
	otherEncodingButton.setFont(font);

	encodingCombo = new Combo(group, SWT.NONE);
	data = new GridData();
	encodingCombo.setFont(font);
	encodingCombo.setLayoutData(data);
	encodingCombo.addModifyListener(new ModifyListener() {
	public void modifyText(ModifyEvent e) {
	updateValidState();
	}
	});

	return group;
	}

	/**
	* Get the default encoding for the object being shown.
	* @return String
	*/
	protected String findDefaultEncoding() {
	return WorkbenchEncoding.getWorkbenchDefaultEncoding();
	}

	/**
	* Return the text for the default encoding button.
	* @return String
	*/
	protected String defaultButtonText() {
	return IDEWorkbenchMessages.format(
	"WorkbenchPreference.defaultEncoding", new String[] { defaultEnc });//$NON-NLS-1$
	}

	/**
	* Populate the encodings combo. Set the text based on the
	* selectedEncoding. If selectedEncoding is null set it to the
	* default.
	* @param encodings
	* @param selectedEncoding
	*/
	private void populateEncodingsCombo(List encodings, String selectedEncoding) {
	String[] encodingStrings = new String[encodings.size()];
	encodings.toArray(encodingStrings);
	encodingCombo.setItems(encodingStrings);

	if (selectedEncoding == null)
	encodingCombo.setText(getDefaultEnc());
	else
	encodingCombo.setText(selectedEncoding);
	}

	private void updateEncodingState(boolean useDefault) {
	defaultEncodingButton.setSelection(useDefault);
	otherEncodingButton.setSelection(!useDefault);
	encodingCombo.setEnabled(!useDefault);
	updateValidState();
	}

	private void updateValidState() {
	boolean isValidNow = isEncodingValid();
	if (isValidNow != isValid) {
	isValid = isValidNow;
	if (isValid) {
	clearErrorMessage();
	} else {
	showErrorMessage(IDEWorkbenchMessages
	.getString("WorkbenchPreference.unsupportedEncoding")); //$NON-NLS-1$
	}
	fireStateChanged(IS_VALID, !isValid, isValid);

	String newValue = getSelectedEncoding();
	if (isValid && !newValue.equals(oldSelectedEncoding)) {
	fireValueChanged(VALUE, oldSelectedEncoding, newValue);
	oldSelectedEncoding = newValue;
	}
	}
	}

	/**
	* Get the encoding current selected.
	* @return String
	*/
	protected String getSelectedEncoding() {
	if (defaultEncodingButton.getSelection()) {
	return defaultEnc;
	}
	return encodingCombo.getText();
	}

	private boolean isEncodingValid() {
	return defaultEncodingButton.getSelection() \|\| isValidEncoding(encodingCombo.getText());
	}

	/**
	* Return whether or not this is a valid encoding.
	* @param enc
	* @return boolean
	*/
	private boolean isValidEncoding(String enc) {
	try {
	return Charset.isSupported(enc);
	} catch (IllegalCharsetNameException e) {
	//This is a valid exception
	return false;
	}

	}

	/**
	* Return the default encoding.
	* @return String
	*/
	protected String getDefaultEnc() {
	return defaultEnc;
	}

	/**
	* Return whether or not the encoding setting changed.
	* @param encodingSetting the setting from the page.
	* @return boolean <code>true</code> if the resource encoding
	* is the same as before.
	*/
	protected boolean hasSameEncoding(String encodingSetting) {

	String current = getStoredValue();

	if (encodingSetting == null) {
	//Changed if default is selected and there is no setting
	return current == null \|\| current.length() == 0;
	}
	return encodingSetting.equals(current);
	}

	}