/*******************************************************************************
* Copyright (c) 2004, 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
*******************************************************************************/
package org.eclipse.ui.ide;
import java.nio.charset.Charset;
import java.nio.charset.IllegalCharsetNameException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.content.IContentDescription;
import org.eclipse.osgi.util.NLS;
import org.eclipse.ui.WorkbenchEncoding;
import org.eclipse.ui.internal.WorkbenchPlugin;
import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;
import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin;
/**
* IDEEncoding is a utility class for managing encoding information that
* includes user preferences from the IDE and core resources.
* <p>
* This class provides all its functionality via static methods.
* It is not intended to be instantiated or subclassed.
* </p>
*
* @see org.eclipse.ui.WorkbenchEncoding
* @see org.eclipse.core.resources.ResourcesPlugin
* @since 3.1
*/
public final class IDEEncoding {
private IDEEncoding () {
// prevent instantiation
}
//The preference for the user entered encodings.
private static String IDE_ENCODINGS_PREFERENCE = "IDE_ENCODINGS_PREFERENCE"; //$NON-NLS-1$
private static String PREFERENCE_SEPARATOR = "'"; //$NON-NLS-1$
/**
* Display constant for the UTF 8 byte order marker for resources.
*/
public static String BOM_UTF_8 = "UTF-8 (BOM)";//$NON-NLS-1$
/**
* Display constant for the UTF 16 big endian byte order marker for
* resources.
*/
public static String BOM_UTF_16BE = "UTF-16 Big-Endian (BOM)";//$NON-NLS-1$
/**
* Display constant for the UTF 16 little endian byte order marker for
* resources.
*/
public static String BOM_UTF_16LE = "UTF-16 Little-Endian (BOM)";//$NON-NLS-1$
/**
* Get all of the available encodings including any that were saved as a
* preference in the IDE or in core resources.
*
* @return List of String
*/
public static List getIDEEncodings() {
List encodings = getIDEEncodingsPreference();
encodings.addAll(WorkbenchEncoding.getDefinedEncodings());
String enc = getResourceEncoding();
if (!(enc == null || encodings.contains(enc))) {
encodings.add(enc);
}
Collections.sort(encodings);
return encodings;
}
/**
* Get the current value of the encoding preference. If the value is not set
* return <code>null</code>.
*
* @return String
*/
public static String getResourceEncoding() {
String preference = ResourcesPlugin.getPlugin().getPluginPreferences().getString(
ResourcesPlugin.PREF_ENCODING);
if (preference == null || preference.length() == 0) {
return null;
}
return preference;
}
/**
* Add value to the list of workbench encodings.
*
* @param value
*/
public static void addIDEEncoding(String value) {
if (WorkbenchEncoding.getDefinedEncodings().contains(value)) {
return;
}
writeEncodingsPreference(value, getIDEEncodingsPreference());
}
/**
* Write the encodings preference. If value is not null
* and not already in the list of currentEncodings add
* it to the list.
* @param value String or <code>null</code>
* @param encodings The list of encodings to write
*/
private static void writeEncodingsPreference(String value, Collection encodings) {
boolean addValue = (value != null);
StringBuffer result = new StringBuffer();
Iterator currentEncodings = encodings.iterator();
while (currentEncodings.hasNext()) {
String string = (String) currentEncodings.next();
result.append(string);
result.append(PREFERENCE_SEPARATOR);
if (addValue && string.equals(value)) {
addValue = false;
}
}
if (addValue) {
result.append(value);
}
IDEWorkbenchPlugin.getDefault().getPreferenceStore().setValue(IDE_ENCODINGS_PREFERENCE,
result.toString());
}
/**
* Get the value of the encodings preference.
*
* @return List
*/
private static List getIDEEncodingsPreference() {
boolean updateRequired = false;
String encodings = IDEWorkbenchPlugin.getDefault().getPreferenceStore().getString(
IDE_ENCODINGS_PREFERENCE);
if (encodings == null || encodings.length() == 0) {
return new ArrayList();
}
ArrayList result = new ArrayList();
//Drop any encodings that are not valid
for (String string : encodings.split(PREFERENCE_SEPARATOR)) {
boolean isSupported;
try {
isSupported = Charset.isSupported(string);
} catch (IllegalCharsetNameException e) {
isSupported = false;
}
if (isSupported) {
result.add(string);
} else{
WorkbenchPlugin.log(NLS.bind(IDEWorkbenchMessages.WorkbenchEncoding_invalidCharset, string));
updateRequired = true;
}
}
if(updateRequired) {
writeEncodingsPreference(null, result);
}
return result;
}
/**
* Clear the IDE encodings preference.
*/
public static void clearUserEncodings() {
IDEWorkbenchPlugin.getDefault().getPreferenceStore().setToDefault(IDE_ENCODINGS_PREFERENCE);
}
/**
* Get the displayable string for the byte order marking from the supplied
* file description.
*
* @param description
* The description to query. May be <code>null</code>.
* @return String or <code>null</code> if the byte order mark cannot be
* found or the description is <code>null</code>.
* @see IContentDescription#getProperty(org.eclipse.core.runtime.QualifiedName)
*/
public static String getByteOrderMarkLabel(IContentDescription description) {
if (description == null) {
return null;
}
byte[] bom = (byte[]) description.getProperty(IContentDescription.BYTE_ORDER_MARK);
if (bom == null) {
return null;
}
if (bom == IContentDescription.BOM_UTF_8) {
return IDEEncoding.BOM_UTF_8;
}
if (bom == IContentDescription.BOM_UTF_16BE) {
return IDEEncoding.BOM_UTF_16BE;
}
if (bom == IContentDescription.BOM_UTF_16LE) {
return IDEEncoding.BOM_UTF_16LE;
}
return null;
}
}