swtresourcemanager.java

这个语法分析器用到的是自顶向下的递归调用的方法

    public static Image decorateImage(Image baseImage, Image decorator) {
    	return decorateImage(baseImage, decorator, BOTTOM_RIGHT);
    }
    
    /**
	 * Returns an image composed of a base image decorated by another image
	 * @param baseImage Image The base image that should be decorated
	 * @param decorator Image The image to decorate the base image
	 * @param corner The corner to place decorator image
	 * @return Image The resulting decorated image
	 */
	public static Image decorateImage(final Image baseImage, final Image decorator, final int corner) {
		HashMap<Image, Image> decoratedMap = m_ImageToDecoratorMap.get(baseImage);
		if (decoratedMap == null) {
			decoratedMap = new HashMap<Image, Image>();
			m_ImageToDecoratorMap.put(baseImage, decoratedMap);
		}
		Image result = decoratedMap.get(decorator);
		if (result == null) {
			Rectangle bid = baseImage.getBounds();
			Rectangle did = decorator.getBounds();
			result = new Image(Display.getCurrent(), bid.width, bid.height);
			GC gc = new GC(result);
			gc.drawImage(baseImage, 0, 0);
			//
			if (corner == TOP_LEFT) {
				gc.drawImage(decorator, 0, 0);
			} else if (corner == TOP_RIGHT) {
				gc.drawImage(decorator, bid.width - did.width - 1, 0);
			} else if (corner == BOTTOM_LEFT) {
				gc.drawImage(decorator, 0, bid.height - did.height - 1);
			} else if (corner == BOTTOM_RIGHT) {
				gc.drawImage(decorator, bid.width - did.width - 1, bid.height - did.height - 1);
			}
			//
			gc.dispose();
			decoratedMap.put(decorator, result);
		}
		return result;
	}

    /**
     * Dispose all of the cached images
     */
    public static void disposeImages() {
        for (Iterator<Image> I = m_ClassImageMap.values().iterator(); I.hasNext();)
             I.next().dispose();
        m_ClassImageMap.clear();
        //
        for (Iterator<HashMap<Image, Image>> I = m_ImageToDecoratorMap.values().iterator(); I.hasNext();) {
			HashMap<Image, Image> decoratedMap = I.next();
			for (Iterator<Image> J = decoratedMap.values().iterator(); J.hasNext();) {
				Image image = J.next();
				image.dispose();
			}
		}
    }

    /**
	 * Dispose cached images in specified section
	 * @param section the section do dispose
	 */
	public static void disposeImages(String section) {
		for (Iterator<String> I = m_ClassImageMap.keySet().iterator(); I.hasNext();) {
			String key = I.next();
			if (!key.startsWith(section + '|'))
				continue;
			Image image = m_ClassImageMap.get(key);
			image.dispose();
			I.remove();
		}
	}

    //////////////////////////////
    // Font support
    //////////////////////////////

    /**
     * Maps font names to fonts
     */
    private static HashMap<String, Font> m_FontMap = new HashMap<String, Font>();

    /**
     * Maps fonts to their bold versions
     */
    private static HashMap<Font, Font> m_FontToBoldFontMap = new HashMap<Font, Font>();

    /**
     * Returns a font based on its name, height and style
     * @param name String The name of the font
     * @param height int The height of the font
     * @param style int The style of the font
     * @return Font The font matching the name, height and style
     */
    public static Font getFont(String name, int height, int style) {
    	return getFont(name, height, style, false, false);
    }


    /**
     * Returns a font based on its name, height and style. 
     * Windows-specific strikeout and underline flags are also supported.
     * @param name String The name of the font
     * @param size int The size of the font
     * @param style int The style of the font
     * @param strikeout boolean The strikeout flag (warning: Windows only)
     * @param underline boolean The underline flag (warning: Windows only)
     * @return Font The font matching the name, height, style, strikeout and underline
     */
	public static Font getFont(String name, int size, int style, boolean strikeout, boolean underline) {
		String fontName = name + '|' + size + '|' + style + '|' + strikeout + '|' + underline;
        Font font = m_FontMap.get(fontName);
        if (font == null) {
        	FontData fontData = new FontData(name, size, style);
    		if (strikeout || underline) {
    			try {
    				Class<?> logFontClass = Class.forName("org.eclipse.swt.internal.win32.LOGFONT"); //$NON-NLS-1$
    				Object logFont = FontData.class.getField("data").get(fontData); //$NON-NLS-1$
    				if (logFont != null && logFontClass != null) {
    					if (strikeout) {
							logFontClass.getField("lfStrikeOut").set(logFont, new Byte((byte) 1)); //$NON-NLS-1$
						}
    					if (underline) {
							logFontClass.getField("lfUnderline").set(logFont, new Byte((byte) 1)); //$NON-NLS-1$
						}
    				}
    			} catch (Throwable e) {
    				System.err.println(
    					"Unable to set underline or strikeout" + " (probably on a non-Windows platform). " + e); //$NON-NLS-1$ //$NON-NLS-2$
    			}
    		}
    		font = new Font(Display.getCurrent(), fontData);
    		m_FontMap.put(fontName, font);
        }
		return font;
	}
    

    /**
     * Return a bold version of the give font
     * @param baseFont Font The font for whoch a bold version is desired
     * @return Font The bold version of the give font
     */
    public static Font getBoldFont(Font baseFont) {
        Font font = m_FontToBoldFontMap.get(baseFont);
        if (font == null) {
            FontData fontDatas[] = baseFont.getFontData();
            FontData data = fontDatas[0];
            font = new Font(Display.getCurrent(), data.getName(), data.getHeight(), SWT.BOLD);
            m_FontToBoldFontMap.put(baseFont, font);
        }
        return font;
    }

    /**
     * Dispose all of the cached fonts
     */
    public static void disposeFonts() {
        for (Iterator<Font> iter = m_FontMap.values().iterator(); iter.hasNext();)
             iter.next().dispose();
        m_FontMap.clear();
    }

	//////////////////////////////
    // CoolBar support
    //////////////////////////////

    /**
     * Fix the layout of the specified CoolBar
     * @param bar CoolBar The CoolBar that shgoud be fixed
     */
    public static void fixCoolBarSize(CoolBar bar) {
        CoolItem[] items = bar.getItems();
        // ensure that each item has control (at least empty one)
        for (int i = 0; i < items.length; i++) {
            CoolItem item = items[i];
            if (item.getControl() == null)
                item.setControl(new Canvas(bar, SWT.NONE) {
                @Override
				public Point computeSize(int wHint, int hHint, boolean changed) {
                    return new Point(20, 20);
                }
            });
        }
        // compute size for each item
        for (int i = 0; i < items.length; i++) {
            CoolItem item = items[i];
            Control control = item.getControl();
            control.pack();
            Point size = control.getSize();
            item.setSize(item.computeSize(size.x, size.y));
        }
    }

    //////////////////////////////
    // Cursor support
    //////////////////////////////

    /**
     * Maps IDs to cursors
     */
    private static HashMap<Integer, Cursor> m_IdToCursorMap = new HashMap<Integer, Cursor>();
 
    /**
     * Returns the system cursor matching the specific ID
     * @param id int The ID value for the cursor
     * @return Cursor The system cursor matching the specific ID
     */
    public static Cursor getCursor(int id) {
        Integer key = new Integer(id);
        Cursor cursor = m_IdToCursorMap.get(key);
        if (cursor == null) {
            cursor = new Cursor(Display.getDefault(), id);
            m_IdToCursorMap.put(key, cursor);
        }
        return cursor;
    }
 
    /**
     * Dispose all of the cached cursors
     */
    public static void disposeCursors() {
        for (Iterator<Cursor> iter = m_IdToCursorMap.values().iterator(); iter.hasNext();)
             iter.next().dispose();
        m_IdToCursorMap.clear();
    }
}