private static String changeLineDelimiter(String code, String lineDelim) {
	try {
		ILineTracker tracker= new DefaultLineTracker();
		tracker.set(code);
		int nLines= tracker.getNumberOfLines();
		if (nLines == 1) {
			return code;
		}

		StringBuffer buf= new StringBuffer();
		for (int i= 0; i < nLines; i++) {
			if (i != 0) {
				buf.append(lineDelim);
			}
			IRegion region = tracker.getLineInformation(i);
			String line= code.substring(region.getOffset(), region.getOffset() + region.getLength());
			buf.append(line);
		}
		return buf.toString();
	} catch (BadLocationException e) {
		// can not happen
		return code;
	}
}
 

/**
 * Converts the given string into an array of lines. The lines
 * don't contain any line delimiter characters.
 *
 * @param input the string
 * @return the string converted into an array of strings. Returns <code>
 * 	null</code> if the input string can't be converted in an array of lines.
 */
public static String[] convertIntoLines(String input) {
	try {
		ILineTracker tracker= new DefaultLineTracker();
		tracker.set(input);
		int size= tracker.getNumberOfLines();
		String result[]= new String[size];
		for (int i= 0; i < size; i++) {
			IRegion region= tracker.getLineInformation(i);
			int offset= region.getOffset();
			result[i]= input.substring(offset, offset + region.getLength());
		}
		return result;
	} catch (BadLocationException e) {
		return null;
	}
}
 

public static String trimIndentation(String source, int tabWidth, int indentWidth, boolean considerFirstLine) {
	try {
		ILineTracker tracker= new DefaultLineTracker();
		tracker.set(source);
		int size= tracker.getNumberOfLines();
		if (size == 1)
			return source;
		String lines[]= new String[size];
		for (int i= 0; i < size; i++) {
			IRegion region= tracker.getLineInformation(i);
			int offset= region.getOffset();
			lines[i]= source.substring(offset, offset + region.getLength());
		}
		Strings.trimIndentation(lines, tabWidth, indentWidth, considerFirstLine);
		StringBuffer result= new StringBuffer();
		int last= size - 1;
		for (int i= 0; i < size; i++) {
			result.append(lines[i]);
			if (i < last)
				result.append(tracker.getLineDelimiter(i));
		}
		return result.toString();
	} catch (BadLocationException e) {
		Assert.isTrue(false,"Can not happend"); //$NON-NLS-1$
		return null;
	}
}
 

/**
 * Change the indent of a, possible multiple line, code string. The given number of indent units is removed,
 * and a new indent string is added.
 * <p>The first line of the code will not be changed (It is considered to have no indent as it might start in
 * the middle of a line).</p>
 *
 * @param code the code to change the indent of
 * @param indentUnitsToRemove the number of indent units to remove from each line (except the first) of the given code
 * @param tabWidth the size of one tab in space equivalents
 * @param indentWidth the width of one indentation unit in space equivalents
 * @param newIndentString the new indent string to be added to all lines (except the first)
 * @param lineDelim the new line delimiter to be used. The returned code will contain only this line delimiter.
 * @return the newly indent code, containing only the given line delimiters.
 * @exception IllegalArgumentException if:
 * <ul>
 * <li>the given <code>indentWidth</code> is lower than zero</li>
 * <li>the given <code>tabWidth</code> is lower than zero</li>
 * <li>the given <code>code</code> is null</li>
 * <li>the given <code>indentUnitsToRemove</code> is lower than zero</li>
 * <li>the given <code>newIndentString</code> is null</li>
 * <li>the given <code>lineDelim</code> is null</li>
 * </ul>
 */
public static String changeIndent(String code, int indentUnitsToRemove, int tabWidth, int indentWidth, String newIndentString, String lineDelim) {
	if (tabWidth < 0 || indentWidth < 0 || code == null || indentUnitsToRemove < 0 || newIndentString == null || lineDelim == null) {
		throw new IllegalArgumentException();
	}

	try {
		ILineTracker tracker= new DefaultLineTracker();
		tracker.set(code);
		int nLines= tracker.getNumberOfLines();
		if (nLines == 1) {
			return code;
		}

		StringBuffer buf= new StringBuffer();

		for (int i= 0; i < nLines; i++) {
			IRegion region= tracker.getLineInformation(i);
			int start= region.getOffset();
			int end= start + region.getLength();
			String line= code.substring(start, end);

			if (i == 0) {  // no indent for first line (contained in the formatted string)
				buf.append(line);
			} else { // no new line after last line
				buf.append(lineDelim);
				buf.append(newIndentString);
				if(indentWidth != 0) {
					buf.append(trimIndent(line, indentUnitsToRemove, tabWidth, indentWidth));
				} else {
					buf.append(line);
				}
			}
		}
		return buf.toString();
	} catch (BadLocationException e) {
		// can not happen
		return code;
	}
}
 

/**
 * Returns the text edits retrieved after changing the indentation of a, possible multi-line, code string.
 *
 * <p>The given number of indent units is removed, and a new indent string is added.</p>
 * <p>The first line of the code will not be changed (It is considered to have no indent as it might start in
 * the middle of a line).</p>
 *
 * @param source The code to change the indent of
 * @param indentUnitsToRemove the number of indent units to remove from each line (except the first) of the given code
 * @param tabWidth the size of one tab in space equivalents
 * @param indentWidth the width of one indentation unit in space equivalents
 * @param newIndentString the new indent string to be added to all lines (except the first)
 * @return returns the resulting text edits
 * @exception IllegalArgumentException if:
 * <ul>
 * <li>the given <code>indentWidth</code> is lower than zero</li>
 * <li>the given <code>tabWidth</code> is lower than zero</li>
 * <li>the given <code>source</code> is null</li>
 * <li>the given <code>indentUnitsToRemove</code> is lower than zero</li>
 * <li>the given <code>newIndentString</code> is null</li>
 * </ul>
 */
public static ReplaceEdit[] getChangeIndentEdits(String source, int indentUnitsToRemove, int tabWidth, int indentWidth, String newIndentString) {
	if (tabWidth < 0 || indentWidth < 0 || source == null || indentUnitsToRemove < 0 || newIndentString == null) {
		throw new IllegalArgumentException();
	}

	ArrayList result= new ArrayList();
	try {
		ILineTracker tracker= new DefaultLineTracker();
		tracker.set(source);
		int nLines= tracker.getNumberOfLines();
		if (nLines == 1)
			return (ReplaceEdit[])result.toArray(new ReplaceEdit[result.size()]);
		for (int i= 1; i < nLines; i++) {
			IRegion region= tracker.getLineInformation(i);
			int offset= region.getOffset();
			String line= source.substring(offset, offset + region.getLength());
			int length= indexOfIndent(line, indentUnitsToRemove, tabWidth, indentWidth);
			if (length >= 0) {
				result.add(new ReplaceEdit(offset, length, newIndentString));
			} else {
				length= measureIndentUnits(line, tabWidth, indentWidth);
				result.add(new ReplaceEdit(offset, length, "")); //$NON-NLS-1$
			}
		}
	} catch (BadLocationException cannotHappen) {
		// can not happen
	}
	return (ReplaceEdit[])result.toArray(new ReplaceEdit[result.size()]);
}
 

public ILineTracker createLineTracker(Object element) {
	return new DefaultLineTracker();
}
 

/**
 * Creates a line tracker for the given element. It is of the same kind as the one that would be
 * used for a newly created document for the given element.
 *
 * @param element the element
 * @return a line tracker for the given element
 */
ILineTracker createLineTracker(Object element);