org.eclipse.help.ui/src/org/eclipse/help/ui/internal/StyledLineWrapper.java - platform/eclipse.platform.ua - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2016 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.help.ui.internal;

 import java.util.ArrayList;
 import java.util.Iterator;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.StyleRange;
 import org.eclipse.swt.custom.StyledTextContent;
 import org.eclipse.swt.custom.TextChangeListener;
 import org.eclipse.swt.graphics.Drawable;
 import org.eclipse.swt.graphics.GC;

 import com.ibm.icu.text.BreakIterator;

 public class StyledLineWrapper implements StyledTextContent {

 	/**
 	 * Internal representation of &lt;b&gt; - unlikely to occur in a text
 	 */
 	public static final String BOLD_CLOSE_TAG = "</@#$b>"; //$NON-NLS-1$
 	/**
 	 * Internal representation of &lt;b&gt; - unlikely to occur in a text
 	 */
 	public static final String BOLD_TAG = "<@#$b>"; //$NON-NLS-1$

 	private Drawable drawable;

 	/** Lines after splitting */
 	private ArrayList<String> lines = new ArrayList<>();

 	/** Style ranges, per line */
 	private ArrayList<StyleRange> lineStyleRanges = new ArrayList<>();

 	/** Character count */
 	private int charCount = -1;

 	/** Line breaker */
 	private static BreakIterator lineBreaker = BreakIterator.getLineInstance();

 	/** Beyond this length (pixels), lines should wrap */
 	public final static int DEFAULT_WIDTH = 350;

 	public int maxWidth;

 	/**
 	 * Constructor
 	 */
 	public StyledLineWrapper(String text, Drawable drawable, int minWidth) {
 		this.drawable = drawable;
 		maxWidth = Math.max(DEFAULT_WIDTH, minWidth);
 		if (text == null || text.length() == 0)
 			text = " "; // use one blank space //$NON-NLS-1$
 		setText(text);
 	}

 	/**
 	 * @see StyledTextContent#addTextChangeListener(TextChangeListener)
 	 */
 	@Override
 	public void addTextChangeListener(TextChangeListener l) {
 		// do nothing
 	}

 	/**
 	 * @see StyledTextContent#getCharCount()
 	 */
 	@Override
 	public int getCharCount() {
 		if (charCount != -1)
 			return charCount;
 		charCount = 0;
 		for (Iterator<String> i = lines.iterator(); i.hasNext();)
 			charCount += i.next().length();
 		return charCount;
 	}

 	/**
 	 * @see StyledTextContent#getLine(int)
 	 */
 	@Override
 	public String getLine(int i) {
 		if ((i >= lines.size()) || (i < 0))
 			SWT.error(SWT.ERROR_INVALID_ARGUMENT);
 		return lines.get(i);
 	}

 	/**
 	 * @see StyledTextContent#getLineAtOffset(int)
 	 */
 	@Override
 	public int getLineAtOffset(int offset) {
 		if (offset >= getCharCount())
 			return getLineCount() - 1;
 		int count = 0;
 		int line = -1;
 		while (count <= offset) {
 			count += getLine(++line).length();
 		}
 		return line;
 	}

 	/**
 	 * @see StyledTextContent#getLineCount()
 	 */
 	@Override
 	public int getLineCount() {
 		if (lines.size() == 0)
 			return 1;
 		return lines.size();
 	}

 	/**
 	 * @see StyledTextContent#getLineDelimiter()
 	 */
 	@Override
 	public String getLineDelimiter() {
 		return null;
 	}

 	/**
 	 * @see StyledTextContent#getOffsetAtLine(int)
 	 */
 	@Override
 	public int getOffsetAtLine(int line) {
 		if (lines.size() == 0)
 			return 0;
 		int offset = 0;
 		for (int i = 0; i < line; i++)
 			offset += getLine(i).length();
 		return offset;
 	}

 	/**
 	 * @see StyledTextContent#getTextRange(int, int)
 	 */
 	@Override
 	public String getTextRange(int start, int end) {
 		int l1 = getLineAtOffset(start);
 		int l2 = getLineAtOffset(end);
 		if (l1 == l2)
 			return getLine(l1).substring(start - getOffsetAtLine(l1),
 					end - start);
 		StringBuffer range = new StringBuffer(getLine(l1).substring(
 				start - getOffsetAtLine(l1)));
 		for (int i = l1 + 1; i < l2; i++)
 			range.append(getLine(i));
 		range.append(getLine(l2).substring(0, end - getOffsetAtLine(l2)));
 		return range.toString();
 	}

 	/**
 	 * @see StyledTextContent#removeTextChangeListener(TextChangeListener)
 	 */
 	@Override
 	public void removeTextChangeListener(TextChangeListener arg0) {
 		// do nothing
 	}

 	/**
 	 * @see StyledTextContent#replaceTextRange(int, int, String)
 	 */
 	@Override
 	public void replaceTextRange(int arg0, int arg1, String arg2) {
 		// do nothing
 	}

 	/**
 	 * @see StyledTextContent#setText(String)
 	 */
 	@Override
 	public void setText(String text) {
 		if (text == null)
 			text = " "; //$NON-NLS-1$
 		processLineBreaks(text);
 		processStyles(text);
 	}

 	/**
 	 * Returns the array of styles.
 	 */
 	public StyleRange[] getStyles() {
 		StyleRange[] array = new StyleRange[lineStyleRanges.size()];
 		lineStyleRanges.toArray(array);
 		return array;
 	}

 	/**
 	 * Create an array of lines with sytles stripped off. Each lines is at most
 	 * MAX_LINE_LENGTH characters.
 	 */
 	private void processLineBreaks(String text) {
 		// Create the original lines with style stripped
 		lines = new ArrayList<>();
 		char[] textChars = getUnstyledText(text).toCharArray();
 		int start = 0;
 		for (int i = start; i < textChars.length; i++) {
 			char ch = textChars[i];
 			if (ch == SWT.CR) {
 				lines.add(new String(textChars, start, i - start));
 				start = i + 1;
 				// if we reached the end, stop
 				if (start >= textChars.length)
 					break;
 				{ // see if the next character is an LF
 					ch = textChars[start];
 					if (ch == SWT.LF) {
 						start++;
 						i++;
 						if (start >= textChars.length)
 							break;
 					}
 				}
 			} else if (ch == SWT.LF) {
 				lines.add(new String(textChars, start, i - start));
 				start = i + 1;
 				if (start >= textChars.length)
 					break;
 			} else if (i == textChars.length - 1) {
 				lines.add(new String(textChars, start, i - start + 1));
 			}
 		}
 		// Break long lines
 		GC gc = new GC(drawable);
 		for (int i = 0; i < lines.size(); i++) {
 			String line = lines.get(i);
 			while (line.length() > 0) {
 				int linebreak = getLineBreak(line, gc);
 				if (linebreak == 0 || linebreak == line.length())
 					break;
 				String newline = line.substring(0, linebreak);
 				lines.remove(i);
 				lines.add(i, newline);
 				line = line.substring(linebreak);
 				lines.add(++i, line);
 			}
 		}
 		gc.dispose();
 	}

 	/**
 	 * Returns the text without the style
 	 */
 	private static String getUnstyledText(String styledText) {
 		return styledText.replaceAll("</?@#\\$b>", ""); //$NON-NLS-1$ //$NON-NLS-2$
 	}

 	/**
 	 * Finds a good line breaking point
 	 */
 	private int getLineBreak(String line, GC gc) {
 		lineBreaker.setText(line);
 		int lastGoodIndex = 0;
 		int currentIndex = lineBreaker.first();
 		int width = gc.textExtent(line.substring(0, currentIndex)).x;
 		while (width < maxWidth && currentIndex != BreakIterator.DONE) {
 			lastGoodIndex = currentIndex;
 			currentIndex = lineBreaker.next();
 			if (currentIndex == BreakIterator.DONE) {
 				break;
 			}
 			width = gc.textExtent(line.substring(0, currentIndex)).x;
 		}
 		return lastGoodIndex;
 	}

 	/**
 	 * Creates all the (bold) style ranges for the text. It is assumed that the
 	 * text has been split across lines.
 	 */
 	private void processStyles(String text) {
 		// create a new array of styles
 		lineStyleRanges = new ArrayList<>();
 		// first, remove the line breaks
 		text = text.replaceAll("\n|\r", ""); //$NON-NLS-1$ //$NON-NLS-2$
 		int offset = 0;
 		do {
 			// create a style
 			StyleRange style = new StyleRange();
 			style.fontStyle = SWT.BOLD;
 			// the index of the starting style in styled text
 			int start = text.indexOf(BOLD_TAG, offset);
 			if (start == -1)
 				break;
 			String prefix = getUnstyledText(text.substring(0, start));
 			style.start = prefix.length();
 			// the index of the ending style in styled text
 			offset = start + 1;
 			int end = text.indexOf(BOLD_CLOSE_TAG, offset);
 			if (end == -1)
 				break;
 			prefix = getUnstyledText(text.substring(0, end));
 			style.length = prefix.length() - style.start;
 			lineStyleRanges.add(style);
 			offset = end + 1;
 		} while (offset < text.length());
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2016 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.help.ui.internal;

	import java.util.ArrayList;
	import java.util.Iterator;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.StyleRange;
	import org.eclipse.swt.custom.StyledTextContent;
	import org.eclipse.swt.custom.TextChangeListener;
	import org.eclipse.swt.graphics.Drawable;
	import org.eclipse.swt.graphics.GC;

	import com.ibm.icu.text.BreakIterator;

	public class StyledLineWrapper implements StyledTextContent {

	/**
	* Internal representation of <b> - unlikely to occur in a text
	*/
	public static final String BOLD_CLOSE_TAG = "</@#$b>"; //$NON-NLS-1$
	/**
	* Internal representation of <b> - unlikely to occur in a text
	*/
	public static final String BOLD_TAG = "<@#$b>"; //$NON-NLS-1$

	private Drawable drawable;

	/** Lines after splitting */
	private ArrayList<String> lines = new ArrayList<>();

	/** Style ranges, per line */
	private ArrayList<StyleRange> lineStyleRanges = new ArrayList<>();

	/** Character count */
	private int charCount = -1;

	/** Line breaker */
	private static BreakIterator lineBreaker = BreakIterator.getLineInstance();

	/** Beyond this length (pixels), lines should wrap */
	public final static int DEFAULT_WIDTH = 350;

	public int maxWidth;

	/**
	* Constructor
	*/
	public StyledLineWrapper(String text, Drawable drawable, int minWidth) {
	this.drawable = drawable;
	maxWidth = Math.max(DEFAULT_WIDTH, minWidth);
	if (text == null \|\| text.length() == 0)
	text = " "; // use one blank space //$NON-NLS-1$
	setText(text);
	}

	/**
	* @see StyledTextContent#addTextChangeListener(TextChangeListener)
	*/
	@Override
	public void addTextChangeListener(TextChangeListener l) {
	// do nothing
	}

	/**
	* @see StyledTextContent#getCharCount()
	*/
	@Override
	public int getCharCount() {
	if (charCount != -1)
	return charCount;
	charCount = 0;
	for (Iterator<String> i = lines.iterator(); i.hasNext();)
	charCount += i.next().length();
	return charCount;
	}

	/**
	* @see StyledTextContent#getLine(int)
	*/
	@Override
	public String getLine(int i) {
	if ((i >= lines.size()) \|\| (i < 0))
	SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	return lines.get(i);
	}

	/**
	* @see StyledTextContent#getLineAtOffset(int)
	*/
	@Override
	public int getLineAtOffset(int offset) {
	if (offset >= getCharCount())
	return getLineCount() - 1;
	int count = 0;
	int line = -1;
	while (count <= offset) {
	count += getLine(++line).length();
	}
	return line;
	}

	/**
	* @see StyledTextContent#getLineCount()
	*/
	@Override
	public int getLineCount() {
	if (lines.size() == 0)
	return 1;
	return lines.size();
	}

	/**
	* @see StyledTextContent#getLineDelimiter()
	*/
	@Override
	public String getLineDelimiter() {
	return null;
	}

	/**
	* @see StyledTextContent#getOffsetAtLine(int)
	*/
	@Override
	public int getOffsetAtLine(int line) {
	if (lines.size() == 0)
	return 0;
	int offset = 0;
	for (int i = 0; i < line; i++)
	offset += getLine(i).length();
	return offset;
	}

	/**
	* @see StyledTextContent#getTextRange(int, int)
	*/
	@Override
	public String getTextRange(int start, int end) {
	int l1 = getLineAtOffset(start);
	int l2 = getLineAtOffset(end);
	if (l1 == l2)
	return getLine(l1).substring(start - getOffsetAtLine(l1),
	end - start);
	StringBuffer range = new StringBuffer(getLine(l1).substring(
	start - getOffsetAtLine(l1)));
	for (int i = l1 + 1; i < l2; i++)
	range.append(getLine(i));
	range.append(getLine(l2).substring(0, end - getOffsetAtLine(l2)));
	return range.toString();
	}

	/**
	* @see StyledTextContent#removeTextChangeListener(TextChangeListener)
	*/
	@Override
	public void removeTextChangeListener(TextChangeListener arg0) {
	// do nothing
	}

	/**
	* @see StyledTextContent#replaceTextRange(int, int, String)
	*/
	@Override
	public void replaceTextRange(int arg0, int arg1, String arg2) {
	// do nothing
	}

	/**
	* @see StyledTextContent#setText(String)
	*/
	@Override
	public void setText(String text) {
	if (text == null)
	text = " "; //$NON-NLS-1$
	processLineBreaks(text);
	processStyles(text);
	}

	/**
	* Returns the array of styles.
	*/
	public StyleRange[] getStyles() {
	StyleRange[] array = new StyleRange[lineStyleRanges.size()];
	lineStyleRanges.toArray(array);
	return array;
	}

	/**
	* Create an array of lines with sytles stripped off. Each lines is at most
	* MAX_LINE_LENGTH characters.
	*/
	private void processLineBreaks(String text) {
	// Create the original lines with style stripped
	lines = new ArrayList<>();
	char[] textChars = getUnstyledText(text).toCharArray();
	int start = 0;
	for (int i = start; i < textChars.length; i++) {
	char ch = textChars[i];
	if (ch == SWT.CR) {
	lines.add(new String(textChars, start, i - start));
	start = i + 1;
	// if we reached the end, stop
	if (start >= textChars.length)
	break;
	{ // see if the next character is an LF
	ch = textChars[start];
	if (ch == SWT.LF) {
	start++;
	i++;
	if (start >= textChars.length)
	break;
	}
	}
	} else if (ch == SWT.LF) {
	lines.add(new String(textChars, start, i - start));
	start = i + 1;
	if (start >= textChars.length)
	break;
	} else if (i == textChars.length - 1) {
	lines.add(new String(textChars, start, i - start + 1));
	}
	}
	// Break long lines
	GC gc = new GC(drawable);
	for (int i = 0; i < lines.size(); i++) {
	String line = lines.get(i);
	while (line.length() > 0) {
	int linebreak = getLineBreak(line, gc);
	if (linebreak == 0 \|\| linebreak == line.length())
	break;
	String newline = line.substring(0, linebreak);
	lines.remove(i);
	lines.add(i, newline);
	line = line.substring(linebreak);
	lines.add(++i, line);
	}
	}
	gc.dispose();
	}

	/**
	* Returns the text without the style
	*/
	private static String getUnstyledText(String styledText) {
	return styledText.replaceAll("</?@#\\$b>", ""); //$NON-NLS-1$ //$NON-NLS-2$
	}

	/**
	* Finds a good line breaking point
	*/
	private int getLineBreak(String line, GC gc) {
	lineBreaker.setText(line);
	int lastGoodIndex = 0;
	int currentIndex = lineBreaker.first();
	int width = gc.textExtent(line.substring(0, currentIndex)).x;
	while (width < maxWidth && currentIndex != BreakIterator.DONE) {
	lastGoodIndex = currentIndex;
	currentIndex = lineBreaker.next();
	if (currentIndex == BreakIterator.DONE) {
	break;
	}
	width = gc.textExtent(line.substring(0, currentIndex)).x;
	}
	return lastGoodIndex;
	}

	/**
	* Creates all the (bold) style ranges for the text. It is assumed that the
	* text has been split across lines.
	*/
	private void processStyles(String text) {
	// create a new array of styles
	lineStyleRanges = new ArrayList<>();
	// first, remove the line breaks
	text = text.replaceAll("\n\|\r", ""); //$NON-NLS-1$ //$NON-NLS-2$
	int offset = 0;
	do {
	// create a style
	StyleRange style = new StyleRange();
	style.fontStyle = SWT.BOLD;
	// the index of the starting style in styled text
	int start = text.indexOf(BOLD_TAG, offset);
	if (start == -1)
	break;
	String prefix = getUnstyledText(text.substring(0, start));
	style.start = prefix.length();
	// the index of the ending style in styled text
	offset = start + 1;
	int end = text.indexOf(BOLD_CLOSE_TAG, offset);
	if (end == -1)
	break;
	prefix = getUnstyledText(text.substring(0, end));
	style.length = prefix.length() - style.start;
	lineStyleRanges.add(style);
	offset = end + 1;
	} while (offset < text.length());
	}
	}