| /* |
| * 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. |
| * |
| */ |
| |
| /* |
| ******************************************************************************* |
| * |
| * Copyright (C) 1999-2003, International Business Machines |
| * Corporation and others. All Rights Reserved. |
| * |
| ******************************************************************************* |
| */ |
| |
| package sun.font; |
| |
| /** |
| * {@code ScriptRun} is used to find runs of characters in |
| * the same script, as defined in the {@code Script} class. |
| * It implements a simple iterator over an array of characters. |
| * The iterator will assign {@code COMMON} and {@code INHERITED} |
| * characters to the same script as the preceding characters. If the |
| * COMMON and INHERITED characters are first, they will be assigned to |
| * the same script as the following characters. |
| * |
| * The iterator will try to match paired punctuation. If it sees an |
| * opening punctuation character, it will remember the script that |
| * was assigned to that character, and assign the same script to the |
| * matching closing punctuation. |
| * |
| * No attempt is made to combine related scripts into a single run. In |
| * particular, Hiragana, Katakana, and Han characters will appear in seperate |
| * runs. |
| |
| * Here is an example of how to iterate over script runs: |
| * <pre> |
| * void printScriptRuns(char[] text) |
| * { |
| * ScriptRun scriptRun = new ScriptRun(text, 0, text.length); |
| * |
| * while (scriptRun.next()) { |
| * int start = scriptRun.getScriptStart(); |
| * int limit = scriptRun.getScriptLimit(); |
| * int script = scriptRun.getScriptCode(); |
| * |
| * System.out.println("Script \"" + Script.getName(script) + "\" from " + |
| * start + " to " + limit + "."); |
| * } |
| * } |
| * </pre> |
| * |
| */ |
| public final class ScriptRun |
| { |
| private char[] text; // fixed once set by constructor |
| private int textStart; |
| private int textLimit; |
| |
| private int scriptStart; // change during iteration |
| private int scriptLimit; |
| private int scriptCode; |
| |
| private int stack[]; // stack used to handle paired punctuation if encountered |
| private int parenSP; |
| |
| public ScriptRun() { |
| // must call init later or we die. |
| } |
| |
| /** |
| * Construct a {@code ScriptRun} object which iterates over a subrange |
| * of the given characetrs. |
| * |
| * @param chars the array of characters over which to iterate. |
| * @param start the index of the first character over which to iterate |
| * @param count the number of characters over which to iterate |
| */ |
| public ScriptRun(char[] chars, int start, int count) |
| { |
| init(chars, start, count); |
| } |
| |
| public void init(char[] chars, int start, int count) |
| { |
| if (chars == null || start < 0 || count < 0 || count > chars.length - start) { |
| throw new IllegalArgumentException(); |
| } |
| |
| text = chars; |
| textStart = start; |
| textLimit = start + count; |
| |
| scriptStart = textStart; |
| scriptLimit = textStart; |
| scriptCode = Script.INVALID_CODE; |
| parenSP = 0; |
| } |
| |
| /** |
| * Get the starting index of the current script run. |
| * |
| * @return the index of the first character in the current script run. |
| */ |
| public int getScriptStart() { |
| return scriptStart; |
| } |
| |
| /** |
| * Get the index of the first character after the current script run. |
| * |
| * @return the index of the first character after the current script run. |
| */ |
| public int getScriptLimit() { |
| return scriptLimit; |
| } |
| |
| /** |
| * Get the script code for the script of the current script run. |
| * |
| * @return the script code for the script of the current script run. |
| * @see Script |
| */ |
| public int getScriptCode() { |
| return scriptCode; |
| } |
| |
| /** |
| * Find the next script run. Returns {@code false} if there |
| * isn't another run, returns {@code true} if there is. |
| * |
| * @return {@code false} if there isn't another run, {@code true} if there is. |
| */ |
| public boolean next() { |
| int startSP = parenSP; // used to find the first new open character |
| |
| // if we've fallen off the end of the text, we're done |
| if (scriptLimit >= textLimit) { |
| return false; |
| } |
| |
| scriptCode = Script.COMMON; |
| scriptStart = scriptLimit; |
| |
| int ch; |
| |
| while ((ch = nextCodePoint()) != DONE) { |
| int sc = ScriptRunData.getScript(ch); |
| int pairIndex = sc == Script.COMMON ? getPairIndex(ch) : -1; |
| |
| // Paired character handling: |
| // |
| // if it's an open character, push it onto the stack. |
| // if it's a close character, find the matching open on the |
| // stack, and use that script code. Any non-matching open |
| // characters above it on the stack will be popped. |
| if (pairIndex >= 0) { |
| if ((pairIndex & 1) == 0) { |
| if (stack == null) { |
| stack = new int[32]; |
| } else if (parenSP == stack.length) { |
| int[] newstack = new int[stack.length + 32]; |
| System.arraycopy(stack, 0, newstack, 0, stack.length); |
| stack = newstack; |
| } |
| |
| stack[parenSP++] = pairIndex; |
| stack[parenSP++] = scriptCode; |
| } else if (parenSP > 0) { |
| int pi = pairIndex & ~1; |
| |
| while ((parenSP -= 2) >= 0 && stack[parenSP] != pi); |
| |
| if (parenSP >= 0) { |
| sc = stack[parenSP+1]; |
| } else { |
| parenSP = 0; |
| } |
| if (parenSP < startSP) { |
| startSP = parenSP; |
| } |
| } |
| } |
| |
| if (sameScript(scriptCode, sc)) { |
| if (scriptCode <= Script.INHERITED && sc > Script.INHERITED) { |
| scriptCode = sc; |
| |
| // now that we have a final script code, fix any open |
| // characters we pushed before we knew the script code. |
| while (startSP < parenSP) { |
| stack[startSP+1] = scriptCode; |
| startSP += 2; |
| } |
| } |
| |
| // if this character is a close paired character, |
| // pop it from the stack |
| if (pairIndex > 0 && (pairIndex & 1) != 0 && parenSP > 0) { |
| parenSP -= 2; |
| } |
| } else { |
| // We've just seen the first character of |
| // the next run. Back over it so we'll see |
| // it again the next time. |
| pushback(ch); |
| |
| // we're outta here |
| break; |
| } |
| } |
| |
| return true; |
| } |
| |
| static final int SURROGATE_START = 0x10000; |
| static final int LEAD_START = 0xd800; |
| static final int LEAD_LIMIT = 0xdc00; |
| static final int TAIL_START = 0xdc00; |
| static final int TAIL_LIMIT = 0xe000; |
| static final int LEAD_SURROGATE_SHIFT = 10; |
| static final int SURROGATE_OFFSET = SURROGATE_START - (LEAD_START << LEAD_SURROGATE_SHIFT) - TAIL_START; |
| |
| static final int DONE = -1; |
| |
| private int nextCodePoint() { |
| if (scriptLimit >= textLimit) { |
| return DONE; |
| } |
| int ch = text[scriptLimit++]; |
| if (ch >= LEAD_START && ch < LEAD_LIMIT && scriptLimit < textLimit) { |
| int nch = text[scriptLimit]; |
| if (nch >= TAIL_START && nch < TAIL_LIMIT) { |
| ++scriptLimit; |
| ch = (ch << LEAD_SURROGATE_SHIFT) + nch + SURROGATE_OFFSET; |
| } |
| } |
| return ch; |
| } |
| |
| private void pushback(int ch) { |
| if (ch >= 0) { |
| if (ch >= 0x10000) { |
| scriptLimit -= 2; |
| } else { |
| scriptLimit -= 1; |
| } |
| } |
| } |
| |
| /** |
| * Compare two script codes to see if they are in the same script. If one script is |
| * a strong script, and the other is INHERITED or COMMON, it will compare equal. |
| * |
| * @param scriptOne one of the script codes. |
| * @param scriptTwo the other script code. |
| * @return {@code true} if the two scripts are the same. |
| * @see Script |
| */ |
| private static boolean sameScript(int scriptOne, int scriptTwo) { |
| return scriptOne == scriptTwo || scriptOne <= Script.INHERITED || scriptTwo <= Script.INHERITED; |
| } |
| |
| /** |
| * Find the highest bit that's set in a word. Uses a binary search through |
| * the bits. |
| * |
| * @param n the word in which to find the highest bit that's set. |
| * @return the bit number (counting from the low order bit) of the highest bit. |
| */ |
| private static byte highBit(int n) |
| { |
| if (n <= 0) { |
| return -32; |
| } |
| |
| byte bit = 0; |
| |
| if (n >= 1 << 16) { |
| n >>= 16; |
| bit += 16; |
| } |
| |
| if (n >= 1 << 8) { |
| n >>= 8; |
| bit += 8; |
| } |
| |
| if (n >= 1 << 4) { |
| n >>= 4; |
| bit += 4; |
| } |
| |
| if (n >= 1 << 2) { |
| n >>= 2; |
| bit += 2; |
| } |
| |
| if (n >= 1 << 1) { |
| n >>= 1; |
| bit += 1; |
| } |
| |
| return bit; |
| } |
| |
| /** |
| * Search the pairedChars array for the given character. |
| * |
| * @param ch the character for which to search. |
| * @return the index of the character in the table, or -1 if it's not there. |
| */ |
| private static int getPairIndex(int ch) |
| { |
| int probe = pairedCharPower; |
| int index = 0; |
| |
| if (ch >= pairedChars[pairedCharExtra]) { |
| index = pairedCharExtra; |
| } |
| |
| while (probe > (1 << 0)) { |
| probe >>= 1; |
| |
| if (ch >= pairedChars[index + probe]) { |
| index += probe; |
| } |
| } |
| |
| if (pairedChars[index] != ch) { |
| index = -1; |
| } |
| |
| return index; |
| } |
| |
| // all common |
| private static int pairedChars[] = { |
| 0x0028, 0x0029, // ascii paired punctuation // common |
| 0x003c, 0x003e, // common |
| 0x005b, 0x005d, // common |
| 0x007b, 0x007d, // common |
| 0x00ab, 0x00bb, // guillemets // common |
| 0x2018, 0x2019, // general punctuation // common |
| 0x201c, 0x201d, // common |
| 0x2039, 0x203a, // common |
| 0x3008, 0x3009, // chinese paired punctuation // common |
| 0x300a, 0x300b, |
| 0x300c, 0x300d, |
| 0x300e, 0x300f, |
| 0x3010, 0x3011, |
| 0x3014, 0x3015, |
| 0x3016, 0x3017, |
| 0x3018, 0x3019, |
| 0x301a, 0x301b |
| }; |
| |
| private static final int pairedCharPower = 1 << highBit(pairedChars.length); |
| private static final int pairedCharExtra = pairedChars.length - pairedCharPower; |
| |
| } |