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SWT is an open source widget toolkit for Java designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.
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/*******************************************************************************
 * Copyright (c) 2000, 2012 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.swt.graphics;


import org.eclipse.swt.internal.win32.*;
import org.eclipse.swt.*;

/**
 * Instances of this class manage operating system resources that
 * define how text looks when it is displayed. Fonts may be constructed
 * by providing a device and either name, size and style information
 * or a FontData object which encapsulates this data.
 * 
 * Application code must explicitly invoke the Font.dispose() 
 * method to release the operating system resources managed by each instance
 * when those instances are no longer required.
 * 
 *
 * @see FontData
 * @see Font snippets
 * @see SWT Examples: GraphicsExample, PaintExample
 * @see Sample code and further information
 */

public final class Font extends Resource {
	
	/**
	 * the handle to the OS font resource
	 * (Warning: This field is platform dependent)
	 * 
	 * IMPORTANT: This field is not part of the SWT
	 * public API. It is marked public only so that it can be shared
	 * within the packages provided by SWT. It is not available on all
	 * platforms and should never be accessed from application code.
	 * 
	 * 
	 * @noreference This field is not intended to be referenced by clients.
	 */
	public int /*long*/ handle;
	
/**
 * Prevents uninitialized instances from being created outside the package.
 */
Font(Device device) {
	super(device);
}

/**	 
 * Constructs a new font given a device and font data
 * which describes the desired font's appearance.
 * 
 * You must dispose the font when it is no longer required. 
 * 
 *
 * @param device the device to create the font on
 * @param fd the FontData that describes the desired font (must not be null)
 * 
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if device is null and there is no current device
 *    ERROR_NULL_ARGUMENT - if the fd argument is null
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES - if a font could not be created from the given font data
 * 
 */
public Font(Device device, FontData fd) {
	super(device);
	init(fd);
	init();
}

/**	 
 * Constructs a new font given a device and an array
 * of font data which describes the desired font's
 * appearance.
 * 
 * You must dispose the font when it is no longer required. 
 * 
 *
 * @param device the device to create the font on
 * @param fds the array of FontData that describes the desired font (must not be null)
 * 
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if device is null and there is no current device
 *    ERROR_NULL_ARGUMENT - if the fds argument is null
 *    ERROR_INVALID_ARGUMENT - if the length of fds is zero
 *    ERROR_NULL_ARGUMENT - if any fd in the array is null
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES - if a font could not be created from the given font data
 * 
 * 
 * @since 2.1
 */
public Font(Device device, FontData[] fds) {
	super(device);
	if (fds == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (fds.length == 0) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	for (int i=0; i
 * You must dispose the font when it is no longer required. 
 * 
 *
 * @param device the device to create the font on
 * @param name the name of the font (must not be null)
 * @param height the font height in points
 * @param style a bit or combination of NORMAL, BOLD, ITALIC
 * 
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if device is null and there is no current device
 *    ERROR_NULL_ARGUMENT - if the name argument is null
 *    ERROR_INVALID_ARGUMENT - if the height is negative
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES - if a font could not be created from the given arguments
 * 
 */
public Font(Device device, String name, int height, int style) {
	super(device);
	if (name == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	init(new FontData (name, height, style));
	init();
}

/*public*/ Font(Device device, String name, float height, int style) {
	super(device);
	if (name == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	init(new FontData (name, height, style));
	init();	
}
void destroy() {
	OS.DeleteObject(handle);
	handle = 0;
}

/**
 * Compares the argument to the receiver, and returns true
 * if they represent the same object using a class
 * specific comparison.
 *
 * @param object the object to compare with this object
 * @return true if the object is the same as this object and false otherwise
 *
 * @see #hashCode
 */
public boolean equals(Object object) {
	if (object == this) return true;
	if (!(object instanceof Font)) return false;
	Font font = (Font) object;
	return device == font.device && handle == font.handle;
}

/**
 * Returns an array of FontDatas representing the receiver.
 * On Windows, only one FontData will be returned per font. On X however, 
 * a Font object may be composed of multiple X 
 * fonts. To support this case, we return an array of font data objects.
 *
 * @return an array of font data objects describing the receiver
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public FontData[] getFontData() {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	LOGFONT logFont = OS.IsUnicode ? (LOGFONT)new LOGFONTW() : new LOGFONTA();
	OS.GetObject(handle, LOGFONT.sizeof, logFont);
	return new FontData[] {FontData.win32_new(logFont, device.computePoints(logFont, handle))};
}

/**
 * Returns an integer hash code for the receiver. Any two 
 * objects that return true when passed to 
 * equals must return the same value for this
 * method.
 *
 * @return the receiver's hash
 *
 * @see #equals
 */
public int hashCode () {
	return (int)/*64*/handle;
}

void init (FontData fd) {
	if (fd == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	LOGFONT logFont = fd.data;
	int lfHeight = logFont.lfHeight;
	logFont.lfHeight = device.computePixels(fd.height);
	handle = OS.CreateFontIndirect(logFont);
	logFont.lfHeight = lfHeight;
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
}

/**
 * Returns true if the font has been disposed,
 * and false otherwise.
 * 
 * This method gets the dispose state for the font.
 * When a font has been disposed, it is an error to
 * invoke any other method (except {@link #dispose()}) using the font.
 *
 * @return true when the font is disposed and false otherwise
 */
public boolean isDisposed() {
	return handle == 0;
}

/**
 * Returns a string containing a concise, human-readable
 * description of the receiver.
 *
 * @return a string representation of the receiver
 */
public String toString () {
	if (isDisposed()) return "Font {*DISPOSED*}";
	return "Font {" + handle + "}";
}

/**	 
 * Invokes platform specific functionality to allocate a new font.
 * 

 * IMPORTANT: This method is not part of the public
 * API for Font. It is marked public only so that it
 * can be shared within the packages provided by SWT. It is not
 * available on all platforms, and should never be called from
 * application code.
 * 
 *
 * @param device the device on which to allocate the color
 * @param handle the handle for the font
 * @return a new font object containing the specified device and handle
 * 
 * @noreference This method is not intended to be referenced by clients.
 */
public static Font win32_new(Device device, int /*long*/ handle) {
	Font font = new Font(device);
	font.handle = handle;
	return font;
}

}