--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.desktop/share/classes/sun/font/FontScaler.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,257 @@
+/*
+ * Copyright (c) 2007, 2014, 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<? extends FontScaler> scalerConstructor = null;
+
+ //Find preferred font scaler
+ //
+ //NB: we can allow property based preferences
+ // (theoretically logic can be font type specific)
+ static {
+ Class<? extends FontScaler> scalerClass = null;
+ Class<?>[] arglst = new Class<?>[] {Font2D.class, int.class,
+ boolean.class, int.class};
+
+ try {
+ @SuppressWarnings("unchecked")
+ Class<? extends FontScaler> tmp = (Class<? extends FontScaler>)
+ (FontUtilities.isOpenJDK ?
+ Class.forName("sun.font.FreetypeFontScaler") :
+ Class.forName("sun.font.T2KFontScaler"));
+ scalerClass = tmp;
+ } 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);
+}