| /* |
| * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package sun.font; |
| |
| import java.awt.geom.GeneralPath; |
| import java.awt.geom.Point2D; |
| import java.awt.geom.Rectangle2D; |
| import java.lang.ref.WeakReference; |
| import java.lang.reflect.Constructor; |
| |
| import sun.java2d.Disposer; |
| import sun.java2d.DisposerRecord; |
| |
| /* FontScaler is "internal interface" to font rasterizer library. |
| * |
| * Access to native rasterizers without going through this interface is |
| * strongly discouraged. In particular, this is important because native |
| * data could be disposed due to runtime font processing error at any time. |
| * |
| * FontScaler represents combination of particular rasterizer implementation |
| * and particular font. It does not include rasterization attributes such as |
| * transform. These attributes are part of native scalerContext object. |
| * This approach allows to share same scaler for different requests related |
| * to the same font file. |
| * |
| * Note that scaler may throw FontScalerException on any operation. |
| * Generally this means that runtime error had happened and scaler is not |
| * usable. Subsequent calls to this scaler should not cause crash but will |
| * likely cause exceptions to be thrown again. |
| * |
| * It is recommended that callee should replace its reference to the scaler |
| * with something else. For instance it could be FontManager.getNullScaler(). |
| * Note that NullScaler is trivial and will not actually rasterize anything. |
| * |
| * Alternatively, callee can use more sophisticated error recovery strategies |
| * and for instance try to substitute failed scaler with new scaler instance |
| * using another font. |
| * |
| * Note that in case of error there is no need to call dispose(). Moreover, |
| * dispose() generally is called by Disposer thread and explicit calls to |
| * dispose might have unexpected sideeffects because scaler can be shared. |
| * |
| * Current disposing logic is the following: |
| * - scaler is registered in the Disposer by the FontManager (on creation) |
| * - scalers are disposed when associated Font2D object (e.g. TruetypeFont) |
| * is garbage collected. That's why this object implements DisposerRecord |
| * interface directly (as it is not used as indicator when it is safe |
| * to release native state) and that's why we have to use WeakReference |
| * to Font internally. |
| * - Majority of Font2D objects are linked from various mapping arrays |
| * (e.g. FontManager.localeFullNamesToFont). So, they are not collected. |
| * This logic only works for fonts created with Font.createFont() |
| * |
| * Notes: |
| * - Eventually we may consider releasing some of the scaler resources if |
| * it was not used for a while but we do not want to be too aggressive on |
| * this (and this is probably more important for Type1 fonts). |
| */ |
| public abstract class FontScaler implements DisposerRecord { |
| |
| private static FontScaler nullScaler = null; |
| private static Constructor<FontScaler> scalerConstructor = null; |
| |
| //Find preferred font scaler |
| // |
| //NB: we can allow property based preferences |
| // (theoretically logic can be font type specific) |
| static { |
| Class scalerClass = null; |
| Class arglst[] = new Class[] {Font2D.class, int.class, |
| boolean.class, int.class}; |
| |
| try { |
| if (FontUtilities.isOpenJDK) { |
| scalerClass = Class.forName("sun.font.FreetypeFontScaler"); |
| } else { |
| scalerClass = Class.forName("sun.font.T2KFontScaler"); |
| } |
| } catch (ClassNotFoundException e) { |
| scalerClass = NullFontScaler.class; |
| } |
| |
| //NB: rewrite using factory? constructor is ugly way |
| try { |
| scalerConstructor = scalerClass.getConstructor(arglst); |
| } catch (NoSuchMethodException e) { |
| //should not happen |
| } |
| } |
| |
| /* This is the only place to instantiate new FontScaler. |
| * Therefore this is very convinient place to register |
| * scaler with Disposer as well as trigger deregistring bad font |
| * in case when scaler reports this. |
| */ |
| public static FontScaler getScaler(Font2D font, |
| int indexInCollection, |
| boolean supportsCJK, |
| int filesize) { |
| FontScaler scaler = null; |
| |
| try { |
| Object args[] = new Object[] {font, indexInCollection, |
| supportsCJK, filesize}; |
| scaler = scalerConstructor.newInstance(args); |
| Disposer.addObjectRecord(font, scaler); |
| } catch (Throwable e) { |
| scaler = nullScaler; |
| |
| //if we can not instantiate scaler assume bad font |
| //NB: technically it could be also because of internal scaler |
| // error but here we are assuming scaler is ok. |
| FontManager fm = FontManagerFactory.getInstance(); |
| fm.deRegisterBadFont(font); |
| } |
| return scaler; |
| } |
| |
| /* |
| * At the moment it is harmless to create 2 null scalers so, technically, |
| * syncronized keyword is not needed. |
| * |
| * But it is safer to keep it to avoid subtle problems if we will be adding |
| * checks like whether scaler is null scaler. |
| */ |
| public static synchronized FontScaler getNullScaler() { |
| if (nullScaler == null) { |
| nullScaler = new NullFontScaler(); |
| } |
| return nullScaler; |
| } |
| |
| protected WeakReference<Font2D> font = null; |
| protected long nativeScaler = 0; //used by decendants |
| //that have native state |
| protected boolean disposed = false; |
| |
| abstract StrikeMetrics getFontMetrics(long pScalerContext) |
| throws FontScalerException; |
| |
| abstract float getGlyphAdvance(long pScalerContext, int glyphCode) |
| throws FontScalerException; |
| |
| abstract void getGlyphMetrics(long pScalerContext, int glyphCode, |
| Point2D.Float metrics) |
| throws FontScalerException; |
| |
| /* |
| * Returns pointer to native GlyphInfo object. |
| * Callee is responsible for freeing this memory. |
| * |
| * Note: |
| * currently this method has to return not 0L but pointer to valid |
| * GlyphInfo object. Because Strike and drawing releated logic does |
| * expect that. |
| * In the future we may want to rework this to allow 0L here. |
| */ |
| abstract long getGlyphImage(long pScalerContext, int glyphCode) |
| throws FontScalerException; |
| |
| abstract Rectangle2D.Float getGlyphOutlineBounds(long pContext, |
| int glyphCode) |
| throws FontScalerException; |
| |
| abstract GeneralPath getGlyphOutline(long pScalerContext, int glyphCode, |
| float x, float y) |
| throws FontScalerException; |
| |
| abstract GeneralPath getGlyphVectorOutline(long pScalerContext, int[] glyphs, |
| int numGlyphs, float x, float y) |
| throws FontScalerException; |
| |
| /* Used by Java2D disposer to ensure native resources are released. |
| Note: this method does not release any of created |
| scaler context objects! */ |
| public void dispose() {} |
| |
| /* At the moment these 3 methods are needed for Type1 fonts only. |
| * For Truetype fonts we extract required info outside of scaler |
| * on java layer. |
| */ |
| abstract int getNumGlyphs() throws FontScalerException; |
| abstract int getMissingGlyphCode() throws FontScalerException; |
| abstract int getGlyphCode(char charCode) throws FontScalerException; |
| |
| /* This method returns table cache used by native layout engine. |
| * This cache is essentially just small collection of |
| * pointers to various truetype tables. See definition of TTLayoutTableCache |
| * in the fontscalerdefs.h for more details. |
| * |
| * Note that tables themselves have same format as defined in the truetype |
| * specification, i.e. font scaler do not need to perform any preprocessing. |
| * |
| * Probably it is better to have API to request pointers to each table |
| * separately instead of requesting pointer to some native structure. |
| * (then there is not need to share its definition by different |
| * implementations of scaler). |
| * However, this means multiple JNI calls and potential impact on performance. |
| * |
| * Note: return value 0 is legal. |
| * This means tables are not available (e.g. type1 font). |
| */ |
| abstract long getLayoutTableCache() throws FontScalerException; |
| |
| /* Used by the OpenType engine for mark positioning. */ |
| abstract Point2D.Float getGlyphPoint(long pScalerContext, |
| int glyphCode, int ptNumber) |
| throws FontScalerException; |
| |
| abstract long getUnitsPerEm(); |
| |
| /* Returns pointer to native structure describing rasterization attributes. |
| Format of this structure is scaler-specific. |
| |
| Callee is responsible for freeing scaler context (using free()). |
| |
| Note: |
| Context is tightly associated with strike and it is actually |
| freed when corresponding strike is being released. |
| */ |
| abstract long createScalerContext(double[] matrix, |
| int aa, int fm, |
| float boldness, float italic, |
| boolean disableHinting); |
| |
| /* Marks context as invalid because native scaler is invalid. |
| Notes: |
| - pointer itself is still valid and has to be released |
| - if pointer to native scaler was cached it |
| should not be neither disposed nor used. |
| it is very likely it is already disposed by this moment. */ |
| abstract void invalidateScalerContext(long ppScalerContext); |
| } |
