阅读器CoolReader开源源码适合于安卓Android

/** * <Detect encoding .> * Copyright (C) <2009> <Fluck,ACC http://androidos.cc/dev> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program 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 for more details. */ package cn.itcreator.android.reader.util; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.net.URL; /** * Detect encoding * @author Fluck * @version 1.0 */ public class BytesEncodingDetect extends Encoding { // Frequency tables to hold the GB, Big5, and EUC-TW character // frequencies int GBFreq[][]; int GBKFreq[][]; int Big5Freq[][]; int Big5PFreq[][]; int EUC_TWFreq[][]; int KRFreq[][]; int JPFreq[][]; // int UnicodeFreq[94][128]; // public static String[] nicename; // public static String[] codings; public boolean debug; public BytesEncodingDetect() { super(); debug = false; GBFreq = new int[94][94]; GBKFreq = new int[126][191]; Big5Freq = new int[94][158]; Big5PFreq = new int[126][191]; EUC_TWFreq = new int[94][94]; KRFreq = new int[94][94]; JPFreq = new int[94][94]; // Initialize the Frequency Table for GB, GBK, Big5, EUC-TW, KR, JP initialize_frequencies(); } public static void main(String argc[]) { BytesEncodingDetect sinodetector; int result = OTHER; int i; sinodetector = new BytesEncodingDetect(); for (i = 0; i < argc.length; i++) { if (argc[i].startsWith("http://") == true) { try { result = sinodetector.detectEncoding(new URL(argc[i])); } catch (Exception e) { System.err.println("Bad URL " + e.toString()); } } else if (argc[i].equals("-d")) { sinodetector.debug = true; continue; } else { result = sinodetector.detectEncoding(new File(argc[i])); } System.out.println(nicename[result]); } } /** * Function : detectEncoding Aruguments: URL Returns : One of the encodings from the Encoding enumeration (GB2312, HZ, BIG5, * EUC_TW, ASCII, or OTHER) Description: This function looks at the URL contents and assigns it a probability score for each * encoding type. The encoding type with the highest probability is returned. */ public int detectEncoding(URL testurl) { byte[] rawtext = new byte[10000]; int bytesread = 0, byteoffset = 0; int guess = OTHER; InputStream chinesestream; try { chinesestream = testurl.openStream(); while ((bytesread = chinesestream.read(rawtext, byteoffset, rawtext.length - byteoffset)) > 0) { byteoffset += bytesread; } ; chinesestream.close(); guess = detectEncoding(rawtext); } catch (Exception e) { System.err.println("Error loading or using URL " + e.toString()); guess = -1; } return guess; } /** * Function : detectEncoding Aruguments: File Returns : One of the encodings from the Encoding enumeration (GB2312, HZ, BIG5, * EUC_TW, ASCII, or OTHER) Description: This function looks at the file and assigns it a probability score for each encoding * type. The encoding type with the highest probability is returned. */ public int detectEncoding(File testfile) { FileInputStream chinesefile; byte[] rawtext; rawtext = new byte[(int) testfile.length()]; try { chinesefile = new FileInputStream(testfile); chinesefile.read(rawtext); chinesefile.close(); } catch (Exception e) { System.err.println("Error: " + e); } return detectEncoding(rawtext); } /** * Function : detectEncoding Aruguments: byte array Returns : One of the encodings from the Encoding enumeration (GB2312, HZ, * BIG5, EUC_TW, ASCII, or OTHER) Description: This function looks at the byte array and assigns it a probability score for * each encoding type. The encoding type with the highest probability is returned. */ public int detectEncoding(byte[] rawtext) { int[] scores; int index, maxscore = 0; int encoding_guess = OTHER; scores = new int[TOTALTYPES]; // Assign Scores scores[GB2312] = gb2312_probability(rawtext); scores[GBK] = gbk_probability(rawtext); scores[GB18030] = gb18030_probability(rawtext); scores[HZ] = hz_probability(rawtext); scores[BIG5] = big5_probability(rawtext); scores[CNS11643] = euc_tw_probability(rawtext); scores[ISO2022CN] = iso_2022_cn_probability(rawtext); scores[UTF8] = utf8_probability(rawtext); scores[UNICODE] = utf16_probability(rawtext); scores[EUC_KR] = euc_kr_probability(rawtext); scores[CP949] = cp949_probability(rawtext); scores[JOHAB] = 0; scores[ISO2022KR] = iso_2022_kr_probability(rawtext); scores[ASCII] = ascii_probability(rawtext); scores[SJIS] = sjis_probability(rawtext); scores[EUC_JP] = euc_jp_probability(rawtext); scores[ISO2022JP] = iso_2022_jp_probability(rawtext); scores[UNICODET] = 0; scores[UNICODES] = 0; scores[ISO2022CN_GB] = 0; scores[ISO2022CN_CNS] = 0; scores[OTHER] = 0; // Tabulate Scores for (index = 0; index < TOTALTYPES; index++) { if (debug) System.err.println("Encoding " + nicename[index] + " score " + scores[index]); if (scores[index] > maxscore) { encoding_guess = index; maxscore = scores[index]; } } // Return OTHER if nothing scored above 50 if (maxscore <= 50) { encoding_guess = OTHER; } return encoding_guess; } /* * Function: gb2312_probability Argument: pointer to byte array Returns : number from 0 to 100 representing probability text * in array uses GB-2312 encoding */ int gb2312_probability(byte[] rawtext) { int i, rawtextlen = 0; int dbchars = 1, gbchars = 1; long gbfreq = 0, totalfreq = 1; float rangeval = 0, freqval = 0; int row, column; // Stage 1: Check to see if characters fit into acceptable ranges rawtextlen = rawtext.length; for (i = 0; i < rawtextlen - 1; i++) { // System.err.println(rawtext[i]); if (rawtext[i] >= 0) { // asciichars++; } else { dbchars++; if ((byte) 0xA1 <= rawtext[i] && rawtext[i] <= (byte) 0xF7 && (byte) 0xA1 <= rawtext[i + 1] && rawtext[i + 1] <= (byte) 0xFE) { gbchars++; totalfreq += 500; row = rawtext[i] + 256 - 0xA1; column = rawtext[i + 1] + 256 - 0xA1; if (GBFreq[row][column] != 0) { gbfreq += GBFreq[row][column]; } else if (15 <= row && row < 55) { // In GB high-freq character range gbfreq += 200; } } i++; } } rangeval = 50 * ((float) gbchars / (float) dbchars); freqval = 50 * ((float) gbfreq / (float) totalfreq); return (int) (rangeval + freqval); } /* * Function: gbk_probability Argument: pointer to byte array Returns : number from 0 to 100 representing probability text in * array uses GBK encoding */ int gbk_probability(byte[] rawtext) { int i, rawtextlen = 0; int dbchars = 1, gbchars = 1; long gbfreq = 0, totalfreq = 1; float rangeval = 0, freqval = 0; int row, column; // Stage 1: Check to see if characters fit into acceptable ranges rawtextlen = rawtext.length; for (i = 0; i < rawtextlen - 1; i++) { // System.err.println(rawtext[i]);