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/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.graphics;


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

/**
 * 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 long handle; 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
  • *
* * @see #dispose() */ public Font(Device device, FontData fd) { super(device); if (fd == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); init(fd.getName(), fd.getHeightF(), fd.getStyle(), fd.string); 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
  • *
* * @see #dispose() * * @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
  • *
* * @see #dispose() */ public Font(Device device, String name, int height, int style) { super(device); init(name, height, style, null); init(); } /*public*/ Font(Device device, String name, float height, int style) { super(device); init(name, height, style, null); init(); } @Override void destroy() { OS.pango_font_description_free(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 */ @Override public boolean equals(Object object) { if (object == this) return true; if (!(object instanceof Font)) return false; return handle == ((Font)object).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); long family = OS.pango_font_description_get_family(handle); int length = C.strlen(family); byte[] buffer = new byte[length]; C.memmove(buffer, family, length); String name = new String(Converter.mbcsToWcs(buffer)); float height = (float)OS.pango_font_description_get_size(handle) / OS.PANGO_SCALE; Point dpi = device.dpi, screenDPI = device.getScreenDPI(); float size = height * screenDPI.y / dpi.y; int pangoStyle = OS.pango_font_description_get_style(handle); int pangoWeight = OS.pango_font_description_get_weight(handle); int style = SWT.NORMAL; if (pangoStyle == OS.PANGO_STYLE_ITALIC) style |= SWT.ITALIC; if (pangoStyle == OS.PANGO_STYLE_OBLIQUE) style |= SWT.ROMAN; if (pangoWeight >= OS.PANGO_WEIGHT_BOLD) style |= SWT.BOLD; long fontString = OS.pango_font_description_to_string (handle); length = C.strlen (fontString); buffer = new byte [length + 1]; C.memmove (buffer, fontString, length); OS.g_free (fontString); FontData data = new FontData(name, size, style); data.string = buffer; return new FontData[]{data}; } /** * 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 * * @noreference This method is not intended to be referenced by clients. */ public static Font gtk_new(Device device, long handle) { Font font = new Font(device); font.handle = handle; /* * When created this way, Font doesn't own its .handle, and * for this reason it can't be disposed. Tell leak detector * to just ignore it. */ font.ignoreNonDisposed(); return font; } /** * 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 */ @Override public int hashCode() { return (int)handle; } void init(String name, float height, int style, byte[] fontString) { if (name == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); if (height < 0) SWT.error(SWT.ERROR_INVALID_ARGUMENT); Point dpi = device.dpi, screenDPI = device.getScreenDPI(); float size = height * dpi.y / screenDPI.y; if (fontString != null) { handle = OS.pango_font_description_from_string (fontString); if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES); } else { handle = OS.pango_font_description_new(); if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES); byte[] buffer = Converter.wcsToMbcs(name, true); OS.pango_font_description_set_family(handle, buffer); if (size > 0) { OS.pango_font_description_set_size(handle, (int)(0.5f + size * OS.PANGO_SCALE)); } OS.pango_font_description_set_stretch(handle, OS.PANGO_STRETCH_NORMAL); int pangoStyle = OS.PANGO_STYLE_NORMAL; int pangoWeight = OS.PANGO_WEIGHT_NORMAL; if ((style & SWT.ITALIC) != 0) pangoStyle = OS.PANGO_STYLE_ITALIC; if ((style & SWT.ROMAN) != 0) pangoStyle = OS.PANGO_STYLE_OBLIQUE; if ((style & SWT.BOLD) != 0) pangoWeight = OS.PANGO_WEIGHT_BOLD; OS.pango_font_description_set_style(handle, pangoStyle); OS.pango_font_description_set_weight(handle, pangoWeight); } } /** * 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 */ @Override 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 */ @Override public String toString () { if (isDisposed()) return "Font {*DISPOSED*}"; return "Font {" + handle + "}"; } }





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