/*******************************************************************************
* Copyright (c) 2002, 2010 Innoopract Informationssysteme GmbH.
* 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:
* Innoopract Informationssysteme GmbH - initial API and implementation
* EclipseSource - ongoing development
******************************************************************************/
package org.eclipse.rwt.internal.util;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Utility class to provide commonly used encoding methods.
*/
public final class EncodingUtil {
private static final Pattern DOUBLE_HYPHEN_PATTERN = Pattern.compile( "--" );
private static final String UNIX_NEWLINE = "\\n";
private static final String NBSP = " ";
/**
* Escapes all double quote and backslash characters in the given input
* string.
*
* @param input the string to process
* @return a copy of the input string with all double quotes and backslashes
* replaced
*/
public static String escapeDoubleQuoted( final String input ) {
StringBuffer resultBuffer = new StringBuffer();
int length = input.length();
for( int i = 0; i < length; i++ ) {
char ch = input.charAt( i );
if( ch == '"' || ch == '\\' ) {
resultBuffer.append( '\\' );
}
resultBuffer.append( ch );
}
return resultBuffer.toString();
}
/**
* Escapes all leading and trailing spaces in the given input string.
*
* @param input the string to process
* @return a copy of the input string with all leading and trailing spaces
* replaced
*/
public static String escapeLeadingTrailingSpaces( final String input ) {
StringBuffer buffer = new StringBuffer();
int beginIndex = 0;
int endIndex = input.length();
while( beginIndex < input.length() && input.charAt( beginIndex ) == ' ' ) {
beginIndex++;
buffer.append( NBSP );
}
while( endIndex > beginIndex && input.charAt( endIndex - 1 ) == ' ' ) {
endIndex--;
}
buffer.append( input.substring( beginIndex, endIndex ) );
int endCount = input.length() - endIndex;
for( int i = 0; i < endCount; i++ ) {
buffer.append( NBSP );
}
return buffer.toString();
}
/**
* Replaces all newline characters in the specified input string with
* <code>\n</code>. All common newline characters are replaced (Unix,
* Windows, and MacOS).
*
* @param input the string to process
* @return a copy of the input string with all newline characters replaced
*/
public static String replaceNewLines( final String input ) {
return replaceNewLines( input, UNIX_NEWLINE );
}
/**
* Replaces all newline characters in the specified input string with the
* given replacement string. All common newline characters are replaced (Unix,
* Windows, and MacOS).
*
* @param input the string to process
* @param replacement the string to replace line feeds with.
* @return a copy of the input string with all newline characters replaced
*/
public static String replaceNewLines( final String input,
final String replacement )
{
StringBuffer resultBuffer = new StringBuffer();
int length = input.length();
int i = 0;
while( i < length ) {
char ch = input.charAt( i );
if( ch == '\n' ) {
resultBuffer.append( replacement );
} else if( ch == '\r' ) {
if( i + 1 < length ) {
char next = input.charAt( i + 1 );
if( ch == '\r' && next == '\n' ) {
i++;
}
}
resultBuffer.append( replacement );
} else {
resultBuffer.append( ch );
}
i++;
}
return resultBuffer.toString();
}
/**
* Replaces white spaces in the specified input string with .
* For correct word wrapping, the last white space in a sequence of white
* spaces is not replaced, if there is a different character following.
* A single white space between words is not replaced whereas a single
* leading white space is replaced.
*
* @param input the string to process
* @return a copy of the input string with white spaces replaced
*/
public static String replaceWhiteSpaces( final String input ) {
StringBuffer buffer = new StringBuffer();
for( int i = 0; i < input.length(); i++ ) {
if( input.charAt( i ) == ' ' ) {
buffer.append( NBSP );
} else {
// Index should be greater then 1 for the case when the string begin
// with single white space.
if( i > 1 ){
// Replaces back with ' ' the single white space between words
// or the last white space in a white spaces sequence.
if( input.charAt( i - 1 ) == ' ' ) {
int start = buffer.length() - NBSP.length();
buffer.replace( start, buffer.length(), " " );
}
}
buffer.append( input.charAt( i ) );
}
}
return buffer.toString();
}
public static String[] splitNewLines( final String input ) {
int length = input.length();
List resultList = new ArrayList();
int start = 0;
char last = 0;
for( int i = 0; i < length; i++ ) {
char ch = input.charAt( i );
if( ch == '\n' ) {
if( last != '\r' ) {
resultList.add( input.substring( start, i ) );
}
start = i + 1;
} else if( ch == '\r' ) {
resultList.add( input.substring( start, i ) );
start = i + 1;
}
last = ch;
}
resultList.add( input.substring( start, length ) );
String[] result = new String[ resultList.size() ];
resultList.toArray( result );
return result;
}
public static String encodeHTMLEntities( final String text ) {
String result = Entities.HTML40.escape( text );
// Encode double-hyphens because they are not allowed inside comments
Matcher matcher = EncodingUtil.DOUBLE_HYPHEN_PATTERN.matcher( result );
result = matcher.replaceAll( "--" );
return result;
}
// Escape unicode characters \u2028 and \u2029 - see bug 304364
public static String removeNonDisplayableChars( final String text ) {
StringBuffer buffer = new StringBuffer();
for( int i = 0; i < text.length(); i++ ) {
char ch = text.charAt( i );
if( !isNonDisplayableChar( ch ) ) {
buffer.append( ch );
}
}
return buffer.toString();
}
public static boolean isNonDisplayableChar( final char ch ) {
return ch == 0x2028 || ch == 0x2029;
}
private EncodingUtil() {
// prevent instantiation
}
}