Use Tree Navigation
public abstract class

Font2D

extends Object
/*
 * Copyright (c) 2003, 2006, 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.Font;
import java.awt.font.FontRenderContext;
import java.awt.geom.AffineTransform;
import java.lang.ref.Reference;
import java.lang.ref.SoftReference;
import java.util.concurrent.ConcurrentHashMap;
import java.util.Locale;

public abstract class Font2D {

   
/* Note: JRE and FONT_CONFIG ranks are identical. I don't know of a reason
     * to distingish these. Possibly if a user adds fonts to the JRE font
     * directory that are the same font as the ones specified in the font
     * configuration but that is more likely to be the legitimate intention
     * than a problem. One reason why these should be the same is that on
     * Linux the JRE fonts ARE the font configuration fonts, and although I
     * believe all are assigned FONT_CONFIG rank, it is conceivable that if
     * this were not so, that some JRE font would not be allowed to joint the
     * family of its siblings which were assigned FONT_CONFIG rank. Giving
     * them the same rank is the easy solution for now at least.
     */

   
public static final int FONT_CONFIG_RANK   = 2;
   
public static final int JRE_RANK     = 2;
   
public static final int TTF_RANK     = 3;
   
public static final int TYPE1_RANK   = 4;
   
public static final int NATIVE_RANK  = 5;
   
public static final int UNKNOWN_RANK = 6;
   
public static final int DEFAULT_RANK = 4;

   
private static final String[] boldNames = {
       
"bold", "demibold", "demi-bold", "demi bold", "negreta", "demi", };

   
private static final String[] italicNames = {
       
"italic", "cursiva", "oblique", "inclined", };

   
private static final String[] boldItalicNames = {
         
"bolditalic", "bold-italic", "bold italic",
         
"boldoblique", "bold-oblique", "bold oblique",
         
"demibold italic", "negreta cursiva","demi oblique", };

   
private static final FontRenderContext DEFAULT_FRC =
       
new FontRenderContext(null, false, false);

   
public Font2DHandle handle;
   
protected String familyName;           /* Family font name (english) */
   
protected String fullName;             /* Full font name (english)   */
   
protected int style = Font.PLAIN;
   
protected FontFamily family;
   
protected int fontRank = DEFAULT_RANK;

   
/*
     * A mapper can be independent of the strike.
     * Perhaps the reference to the mapper ought to be held on the
     * scaler, as it may be implemented via scaler functionality anyway
     * and so the mapper would be useless if its native portion was
     * freed when the scaler was GC'd.
     */

   
protected CharToGlyphMapper mapper;

   
/*
     * The strike cache is maintained per "Font2D" as that is the
     * principal object by which you look up fonts.
     * It means more Hashmaps, but look ups can be quicker because
     * the map will have fewer entries, and there's no need to try to
     * make the Font2D part of the key.
     */

   
protected ConcurrentHashMap<FontStrikeDesc, Reference>
        strikeCache
= new ConcurrentHashMap<FontStrikeDesc, Reference>();

   
/* Store the last Strike in a Reference object.
     * Similarly to the strike that was stored on a C++ font object,
     * this is an optimisation which helps if multiple clients (ie
     * typically SunGraphics2D instances) are using the same font, then
     * as may be typical of many UIs, they are probably using it in the
     * same style, so it can be a win to first quickly check if the last
     * strike obtained from this Font2D satifies the needs of the next
     * client too.
     * This pre-supposes that a FontStrike is a shareable object, which
     * it should.
     */

   
protected Reference lastFontStrike = new SoftReference(null);

   
/*
     * POSSIBLE OPTIMISATION:
     * Array of length 1024 elements of 64 bits indicating if a font
     * contains these. This kind of information can be shared between
     * all point sizes.
     * if corresponding bit in knownBitmaskMap is set then canDisplayBitmaskMap
     * is valid. This is 16Kbytes of data per composite font style.
     * What about UTF-32 and surrogates?
     * REMIND: This is too much storage. Probably can only cache this
     * information for latin range, although possibly OK to store all
     * for just the "logical" fonts.
     * Or instead store arrays of subranges of 1024 bits (128 bytes) in
     * the range below surrogate pairs.
     */

//     protected long[] knownBitmaskMap;
//     protected long[] canDisplayBitmaskMap;

   
/* Returns the "real" style of this Font2D. Eg the font face
     * Lucida Sans Bold" has a real style of Font.BOLD, even though
     * it may be able to used to simulate bold italic
     */

   
public int getStyle() {
       
return style;
   
}
   
protected void setStyle() {

       
String fName = fullName.toLowerCase();

       
for (int i=0; i < boldItalicNames.length; i++) {
           
if (fName.indexOf(boldItalicNames[i]) != -1) {
                style
= Font.BOLD|Font.ITALIC;
               
return;
           
}
       
}

       
for (int i=0; i < italicNames.length; i++) {
           
if (fName.indexOf(italicNames[i]) != -1) {
                style
= Font.ITALIC;
               
return;
           
}
       
}

       
for (int i=0; i < boldNames.length; i++) {
           
if (fName.indexOf(boldNames[i]) != -1 ) {
                style
= Font.BOLD;
               
return;
           
}
       
}
   
}


   
int getRank() {
       
return fontRank;
   
}

   
void setRank(int rank) {
        fontRank
= rank;
   
}

    abstract
CharToGlyphMapper getMapper();



   
/* This isn't very efficient but its infrequently used.
     * StandardGlyphVector uses it when the client assigns the glyph codes.
     * These may not be valid. This validates them substituting the missing
     * glyph elsewhere.
     */

   
protected int getValidatedGlyphCode(int glyphCode) {
       
if (glyphCode < 0 || glyphCode >= getMapper().getNumGlyphs()) {
            glyphCode
= getMapper().getMissingGlyphCode();
       
}
       
return glyphCode;
   
}

   
/*
     * Creates an appropriate strike for the Font2D subclass
     */

    abstract
FontStrike createStrike(FontStrikeDesc desc);

   
/* this may be useful for APIs like canDisplay where the answer
     * is dependent on the font and its scaler, but not the strike.
     * If no strike has ever been returned, then create a one that matches
     * this font with the default FRC. It will become the lastStrike and
     * there's a good chance that the next call will be to get exactly that
     * strike.
     */

   
public FontStrike getStrike(Font font) {
       
FontStrike strike = (FontStrike)lastFontStrike.get();
       
if (strike != null) {
           
return strike;
       
} else {
           
return getStrike(font, DEFAULT_FRC);
       
}
   
}

   
/* SunGraphics2D has font, tx, aa and fm. From this info
     * can get a Strike object from the cache, creating it if necessary.
     * This code is designed for multi-threaded access.
     * For that reason it creates a local FontStrikeDesc rather than filling
     * in a shared one. Up to two AffineTransforms and one FontStrikeDesc will
     * be created by every lookup. This appears to perform more than
     * adequately. But it may make sense to expose FontStrikeDesc
     * as a parameter so a caller can use its own.
     * In such a case if a FontStrikeDesc is stored as a key then
     * we would need to use a private copy.
     *
     * Note that this code doesn't prevent two threads from creating
     * two different FontStrike instances and having one of the threads
     * overwrite the other in the map. This is likely to be a rare
     * occurrence and the only consequence is that these callers will have
     * different instances of the strike, and there'd be some duplication of
     * population of the strikes. However since users of these strikes are
     * transient, then the one that was overwritten would soon be freed.
     * If there is any problem then a small synchronized block would be
     * required with its attendant consequences for MP scaleability.
     */

   
public FontStrike getStrike(Font font, AffineTransform devTx,
                               
int aa, int fm) {

       
/* Create the descriptor which is used to identify a strike
         * in the strike cache/map. A strike is fully described by
         * the attributes of this descriptor.
         */

       
/* REMIND: generating garbage and doing computation here in order
         * to include pt size in the tx just for a lookup! Figure out a
         * better way.
         */

       
double ptSize = font.getSize2D();
       
AffineTransform glyphTx = (AffineTransform)devTx.clone();
        glyphTx
.scale(ptSize, ptSize);
       
if (font.isTransformed()) {
            glyphTx
.concatenate(font.getTransform());
       
}
       
FontStrikeDesc desc = new FontStrikeDesc(devTx, glyphTx,
                                                 font
.getStyle(), aa, fm);
       
return getStrike(desc, false);
   
}

   
public FontStrike getStrike(Font font, AffineTransform devTx,
                               
AffineTransform glyphTx,
                               
int aa, int fm) {

       
/* Create the descriptor which is used to identify a strike
         * in the strike cache/map. A strike is fully described by
         * the attributes of this descriptor.
         */

       
FontStrikeDesc desc = new FontStrikeDesc(devTx, glyphTx,
                                                 font
.getStyle(), aa, fm);
       
return getStrike(desc, false);
   
}

   
public FontStrike getStrike(Font font, FontRenderContext frc) {

       
AffineTransform at = frc.getTransform();
       
double ptSize = font.getSize2D();
        at
.scale(ptSize, ptSize);
       
if (font.isTransformed()) {
            at
.concatenate(font.getTransform());
       
}
       
int aa = FontStrikeDesc.getAAHintIntVal(this, font, frc);
       
int fm = FontStrikeDesc.getFMHintIntVal(frc.getFractionalMetricsHint());
       
FontStrikeDesc desc = new FontStrikeDesc(frc.getTransform(),
                                                 at
, font.getStyle(),
                                                 aa
, fm);
       
return getStrike(desc, false);
   
}

   
FontStrike getStrike(FontStrikeDesc desc) {
       
return getStrike(desc, true);
   
}

   
private FontStrike getStrike(FontStrikeDesc desc, boolean copy) {
       
/* Before looking in the map, see if the descriptor matches the
         * last strike returned from this Font2D. This should often be a win
         * since its common for the same font, in the same size to be
         * used frequently, for example in many parts of a UI.
         *
         * If its not the same then we use the descriptor to locate a
         * Reference to the strike. If it exists and points to a strike,
         * then we update the last strike to refer to that and return it.
         *
         * If the key isn't in the map, or its reference object has been
         * collected, then we create a new strike, put it in the map and
         * set it to be the last strike.
         */

       
FontStrike strike = (FontStrike)lastFontStrike.get();
       
if (strike != null && desc.equals(strike.desc)) {
           
//strike.lastlookupTime = System.currentTimeMillis();
           
return strike;
       
} else {
           
Reference strikeRef = strikeCache.get(desc);
           
if (strikeRef != null) {
                strike
= (FontStrike)strikeRef.get();
               
if (strike != null) {
                   
//strike.lastlookupTime = System.currentTimeMillis();
                    lastFontStrike
= new SoftReference(strike);
                   
StrikeCache.refStrike(strike);
                   
return strike;
               
} else {
                   
/* We have found a cleared reference that has not yet
                     * been removed by the disposer.
                     * If we make this reference unreachable by removing it
                     * from the map,or overwriting it with a new reference to
                     * a new strike, then it is possible it may never be
                     * enqueued for disposal. That is the implication of
                     * the docs for java.lang.ref. So on finding a cleared
                     * reference, we need to dispose the native resources,
                     * if they haven't already been freed.
                     * The reference object needs to have a reference to
                     * the disposer instance for this to occur.
                     */

                 
((StrikeCache.DisposableStrike)strikeRef)
                     
.getDisposer().dispose();
               
}
           
}
           
/* When we create a new FontStrike instance, we *must*
             * ask the StrikeCache for a reference. We must then ensure
             * this reference remains reachable, by storing it in the
             * Font2D's strikeCache map.
             * So long as the Reference is there (reachable) then if the
             * reference is cleared, it will be enqueued for disposal.
             * If for some reason we explicitly remove this reference, it
             * must only be done when holding a strong reference to the
             * referent (the FontStrike), or if the reference is cleared,
             * then we must explicitly "dispose" of the native resources.
             * The only place this currently happens is in this same method,
             * where we find a cleared reference and need to overwrite it
             * here with a new reference.
             * Clearing the whilst holding a strong reference, should only
             * be done if the
             */

           
if (copy) {
                desc
= new FontStrikeDesc(desc);
           
}
            strike
= createStrike(desc);
           
//StrikeCache.addStrike();
            strikeRef
= StrikeCache.getStrikeRef(strike);
            strikeCache
.put(desc, strikeRef);
           
//strike.lastlookupTime = System.currentTimeMillis();
            lastFontStrike
= new SoftReference(strike);
           
StrikeCache.refStrike(strike);
           
return strike;
       
}
   
}

   
void removeFromCache(FontStrikeDesc desc) {
       
Reference ref = strikeCache.get(desc);
       
if (ref != null) {
           
Object o = ref.get();
           
if (o == null) {
                strikeCache
.remove(desc);
           
}
       
}
   
}

   
/**
     * The length of the metrics array must be >= 8.  This method will
     * store the following elements in that array before returning:
     *    metrics[0]: ascent
     *    metrics[1]: descent
     *    metrics[2]: leading
     *    metrics[3]: max advance
     *    metrics[4]: strikethrough offset
     *    metrics[5]: strikethrough thickness
     *    metrics[6]: underline offset
     *    metrics[7]: underline thickness
     */

   
public void getFontMetrics(Font font, AffineTransform at,
                               
Object aaHint, Object fmHint,
                               
float metrics[]) {
       
/* This is called in just one place in Font with "at" == identity.
         * Perhaps this can be eliminated.
         */

       
int aa = FontStrikeDesc.getAAHintIntVal(aaHint, this, font.getSize());
       
int fm = FontStrikeDesc.getFMHintIntVal(fmHint);
       
FontStrike strike = getStrike(font, at, aa, fm);
       
StrikeMetrics strikeMetrics = strike.getFontMetrics();
        metrics
[0] = strikeMetrics.getAscent();
        metrics
[1] = strikeMetrics.getDescent();
        metrics
[2] = strikeMetrics.getLeading();
        metrics
[3] = strikeMetrics.getMaxAdvance();

        getStyleMetrics
(font.getSize2D(), metrics, 4);
   
}

   
/**
     * The length of the metrics array must be >= offset+4, and offset must be
     * >= 0.  Typically offset is 4.  This method will
     * store the following elements in that array before returning:
     *    metrics[off+0]: strikethrough offset
     *    metrics[off+1]: strikethrough thickness
     *    metrics[off+2]: underline offset
     *    metrics[off+3]: underline thickness
     *
     * Note that this implementation simply returns default values;
     * subclasses can override this method to provide more accurate values.
     */

   
public void getStyleMetrics(float pointSize, float[] metrics, int offset) {
        metrics
[offset] = -metrics[0] / 2.5f;
        metrics
[offset+1] = pointSize / 12;
        metrics
[offset+2] = metrics[offset+1] / 1.5f;
        metrics
[offset+3] = metrics[offset+1];
   
}

   
/**
     * The length of the metrics array must be >= 4.  This method will
     * store the following elements in that array before returning:
     *    metrics[0]: ascent
     *    metrics[1]: descent
     *    metrics[2]: leading
     *    metrics[3]: max advance
     */

   
public void getFontMetrics(Font font, FontRenderContext frc,
                               
float metrics[]) {
       
StrikeMetrics strikeMetrics = getStrike(font, frc).getFontMetrics();
        metrics
[0] = strikeMetrics.getAscent();
        metrics
[1] = strikeMetrics.getDescent();
        metrics
[2] = strikeMetrics.getLeading();
        metrics
[3] = strikeMetrics.getMaxAdvance();
   
}

   
/* Currently the layout code calls this. May be better for layout code
     * to check the font class before attempting to run, rather than needing
     * to promote this method up from TrueTypeFont
     */

   
byte[] getTableBytes(int tag) {
       
return null;
   
}

   
/* for layout code */
   
protected long getUnitsPerEm() {
       
return 2048;
   
}

   
boolean supportsEncoding(String encoding) {
       
return false;
   
}

   
public boolean canDoStyle(int style) {
       
return (style == this.style);
   
}

   
/*
     * All the important subclasses override this which is principally for
     * the TrueType 'gasp' table.
     */

   
public boolean useAAForPtSize(int ptsize) {
       
return true;
   
}

   
public boolean hasSupplementaryChars() {
       
return false;
   
}

   
/* The following methods implement public methods on java.awt.Font */
   
public String getPostscriptName() {
       
return fullName;
   
}

   
public String getFontName(Locale l) {
       
return fullName;
   
}

   
public String getFamilyName(Locale l) {
       
return familyName;
   
}

   
public int getNumGlyphs() {
       
return getMapper().getNumGlyphs();
   
}

   
public int charToGlyph(int wchar) {
       
return getMapper().charToGlyph(wchar);
   
}

   
public int getMissingGlyphCode() {
       
return getMapper().getMissingGlyphCode();
   
}

   
public boolean canDisplay(char c) {
       
return getMapper().canDisplay(c);
   
}

   
public boolean canDisplay(int cp) {
       
return getMapper().canDisplay(cp);
   
}

   
public byte getBaselineFor(char c) {
       
return Font.ROMAN_BASELINE;
   
}

   
public float getItalicAngle(Font font, AffineTransform at,
                               
Object aaHint, Object fmHint) {
       
/* hardwire psz=12 as that's typical and AA vs non-AA for 'gasp' mode
         * isn't important for the caret slope of this rarely used API.
         */

       
int aa = FontStrikeDesc.getAAHintIntVal(aaHint, this, 12);
       
int fm = FontStrikeDesc.getFMHintIntVal(fmHint);
       
FontStrike strike = getStrike(font, at, aa, fm);
       
StrikeMetrics metrics = strike.getFontMetrics();
       
if (metrics.ascentY == 0 || metrics.ascentX == 0) {
           
return 0f;
       
} else {
           
/* ascent is "up" from the baseline so its typically
             * a negative value, so we need to compensate
             */

           
return metrics.ascentX/-metrics.ascentY;
       
}
   
}

}