Added: tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetMatch.java URL: http://svn.apache.org/viewvc/tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetMatch.java?rev=1723223&view=auto ============================================================================== --- tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetMatch.java (added) +++ tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetMatch.java Wed Jan 6 03:50:50 2016 @@ -0,0 +1,286 @@ +/** + * ****************************************************************************** + * Copyright (C) 2005-2007, International Business Machines Corporation and * + * others. All Rights Reserved. * + * ****************************************************************************** + */ +package org.apache.tika.parser.txt; + +import java.io.ByteArrayInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.InputStreamReader; +import java.io.Reader; + + +/** + * This class represents a charset that has been identified by a CharsetDetector + * as a possible encoding for a set of input data. From an instance of this + * class, you can ask for a confidence level in the charset identification, + * or for Java Reader or String to access the original byte data in Unicode form. + * <p/> + * Instances of this class are created only by CharsetDetectors. + * <p/> + * Note: this class has a natural ordering that is inconsistent with equals. + * The natural ordering is based on the match confidence value. + * + * @stable ICU 3.4 + */ +public class CharsetMatch implements Comparable<CharsetMatch> { + + + /** + * Bit flag indicating the match is based on the the encoding scheme. + * + * @see #getMatchType + * @stable ICU 3.4 + */ + static public final int ENCODING_SCHEME = 1; + /** + * Bit flag indicating the match is based on the presence of a BOM. + * + * @see #getMatchType + * @stable ICU 3.4 + */ + static public final int BOM = 2; + /** + * Bit flag indicating he match is based on the declared encoding. + * + * @see #getMatchType + * @stable ICU 3.4 + */ + static public final int DECLARED_ENCODING = 4; + /** + * Bit flag indicating the match is based on language statistics. + * + * @see #getMatchType + * @stable ICU 3.4 + */ + static public final int LANG_STATISTICS = 8; + // + // Private Data + // + private int fConfidence; + private CharsetRecognizer fRecognizer; + private byte[] fRawInput = null; // Original, untouched input bytes. + // If user gave us a byte array, this is it. + private int fRawLength; // Length of data in fRawInput array. + private InputStream fInputStream = null; // User's input stream, or null if the user + + /* + * Constructor. Implementation internal + */ + CharsetMatch(CharsetDetector det, CharsetRecognizer rec, int conf) { + fRecognizer = rec; + fConfidence = conf; + + // The references to the original aplication input data must be copied out + // of the charset recognizer to here, in case the application resets the + // recognizer before using this CharsetMatch. + if (det.fInputStream == null) { + // We only want the existing input byte data if it came straight from the user, + // not if is just the head of a stream. + fRawInput = det.fRawInput; + fRawLength = det.fRawLength; + } + fInputStream = det.fInputStream; + } + + /** + * Create a java.io.Reader for reading the Unicode character data corresponding + * to the original byte data supplied to the Charset detect operation. + * <p/> + * CAUTION: if the source of the byte data was an InputStream, a Reader + * can be created for only one matching char set using this method. If more + * than one charset needs to be tried, the caller will need to reset + * the InputStream and create InputStreamReaders itself, based on the charset name. + * + * @return the Reader for the Unicode character data. + * + * @stable ICU 3.4 + */ + public Reader getReader() { + InputStream inputStream = fInputStream; + + if (inputStream == null) { + inputStream = new ByteArrayInputStream(fRawInput, 0, fRawLength); + } + + try { + inputStream.reset(); + return new InputStreamReader(inputStream, getName()); + } catch (IOException e) { + return null; + } + } + + /** + * Create a Java String from Unicode character data corresponding + * to the original byte data supplied to the Charset detect operation. + * + * @return a String created from the converted input data. + * + * @stable ICU 3.4 + */ + public String getString() throws java.io.IOException { + return getString(-1); + + } + + /** + * Create a Java String from Unicode character data corresponding + * to the original byte data supplied to the Charset detect operation. + * The length of the returned string is limited to the specified size; + * the string will be trunctated to this length if necessary. A limit value of + * zero or less is ignored, and treated as no limit. + * + * @param maxLength The maximium length of the String to be created when the + * source of the data is an input stream, or -1 for + * unlimited length. + * @return a String created from the converted input data. + * + * @stable ICU 3.4 + */ + public String getString(int maxLength) throws java.io.IOException { + String result = null; + if (fInputStream != null) { + StringBuffer sb = new StringBuffer(); + char[] buffer = new char[1024]; + Reader reader = getReader(); + int max = maxLength < 0 ? Integer.MAX_VALUE : maxLength; + int bytesRead = 0; + + while ((bytesRead = reader.read(buffer, 0, Math.min(max, 1024))) >= 0) { + sb.append(buffer, 0, bytesRead); + max -= bytesRead; + } + + reader.close(); + + return sb.toString(); + } else { + result = new String(fRawInput, getName()); + } + return result; + + } + + /** + * Get an indication of the confidence in the charset detected. + * Confidence values range from 0-100, with larger numbers indicating + * a better match of the input data to the characteristics of the + * charset. + * + * @return the confidence in the charset match + * + * @stable ICU 3.4 + */ + public int getConfidence() { + return fConfidence; + } + + /** + * Return flags indicating what it was about the input data + * that caused this charset to be considered as a possible match. + * The result is a bitfield containing zero or more of the flags + * ENCODING_SCHEME, BOM, DECLARED_ENCODING, and LANG_STATISTICS. + * A result of zero means no information is available. + * <p> + * Note: currently, this method always returns zero. + * <p> + * + * @return the type of match found for this charset. + * + * @draft ICU 3.4 + * @provisional This API might change or be removed in a future release. + */ + public int getMatchType() { +// TODO: create a list of enum-like constants for common combinations of types of matches. + return 0; + } + + /** + * Get the name of the detected charset. + * The name will be one that can be used with other APIs on the + * platform that accept charset names. It is the "Canonical name" + * as defined by the class java.nio.charset.Charset; for + * charsets that are registered with the IANA charset registry, + * this is the MIME-preferred registerd name. + * + * @see java.nio.charset.Charset + * @see java.io.InputStreamReader + * + * @return The name of the charset. + * + * @stable ICU 3.4 + */ + public String getName() { + return fRecognizer.getName(); + } + + /** + * Get the ISO code for the language of the detected charset. + * + * @return The ISO code for the language or <code>null</code> if the language cannot be determined. + * + * @stable ICU 3.4 + */ + public String getLanguage() { + return fRecognizer.getLanguage(); + } + + /** + * Compare to other CharsetMatch objects. + * Comparison is based on the match confidence value, which + * allows CharsetDetector.detectAll() to order its results. + * + * @param o the CharsetMatch object to compare against. + * @return a negative integer, zero, or a positive integer as the + * confidence level of this CharsetMatch + * is less than, equal to, or greater than that of + * the argument. + * @throws ClassCastException if the argument is not a CharsetMatch. + * @stable ICU 3.4 + */ + public int compareTo(CharsetMatch other) { + int compareResult = 0; + if (this.fConfidence > other.fConfidence) { + compareResult = 1; + } else if (this.fConfidence < other.fConfidence) { + compareResult = -1; + } + return compareResult; + } + + /** + * compare this CharsetMatch to another based on confidence value + * @param o the CharsetMatch object to compare against + * @return true if equal + */ + public boolean equals(Object o) { + if (o instanceof CharsetMatch) { + CharsetMatch that = (CharsetMatch) o; + return (this.fConfidence == that.fConfidence); + } + + return false; + } + + /** + * generates a hashCode based on the confidence value + * @return the hashCode + */ + public int hashCode() { + return fConfidence; + } + // gave us a byte array. + + public String toString() { + String s = "Match of " + fRecognizer.getName(); + if (fRecognizer.getLanguage() != null) { + s += " in " + fRecognizer.getLanguage(); + } + s += " with confidence " + fConfidence; + return s; + } +}
Added: tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_2022.java URL: http://svn.apache.org/viewvc/tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_2022.java?rev=1723223&view=auto ============================================================================== --- tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_2022.java (added) +++ tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_2022.java Wed Jan 6 03:50:50 2016 @@ -0,0 +1,163 @@ +/* +******************************************************************************* +* Copyright (C) 2005 - 2008, International Business Machines Corporation and * +* others. All Rights Reserved. * +******************************************************************************* +*/ +package org.apache.tika.parser.txt; + +/** + * class CharsetRecog_2022 part of the ICU charset detection imlementation. + * This is a superclass for the individual detectors for + * each of the detectable members of the ISO 2022 family + * of encodings. + * <p/> + * The separate classes are nested within this class. + * + * @internal + */ +abstract class CharsetRecog_2022 extends CharsetRecognizer { + + + /** + * Matching function shared among the 2022 detectors JP, CN and KR + * Counts up the number of legal an unrecognized escape sequences in + * the sample of text, and computes a score based on the total number & + * the proportion that fit the encoding. + * + * @param text the byte buffer containing text to analyse + * @param textLen the size of the text in the byte. + * @param escapeSequences the byte escape sequences to test for. + * @return match quality, in the range of 0-100. + */ + int match(byte[] text, int textLen, byte[][] escapeSequences) { + int i, j; + int escN; + int hits = 0; + int misses = 0; + int shifts = 0; + int quality; + scanInput: + for (i = 0; i < textLen; i++) { + if (text[i] == 0x1b) { + checkEscapes: + for (escN = 0; escN < escapeSequences.length; escN++) { + byte[] seq = escapeSequences[escN]; + + if ((textLen - i) < seq.length) { + continue checkEscapes; + } + + for (j = 1; j < seq.length; j++) { + if (seq[j] != text[i + j]) { + continue checkEscapes; + } + } + + hits++; + i += seq.length - 1; + continue scanInput; + } + + misses++; + } + + if (text[i] == 0x0e || text[i] == 0x0f) { + // Shift in/out + shifts++; + } + } + + if (hits == 0) { + return 0; + } + + // + // Initial quality is based on relative proportion of recongized vs. + // unrecognized escape sequences. + // All good: quality = 100; + // half or less good: quality = 0; + // linear inbetween. + quality = (100 * hits - 100 * misses) / (hits + misses); + + // Back off quality if there were too few escape sequences seen. + // Include shifts in this computation, so that KR does not get penalized + // for having only a single Escape sequence, but many shifts. + if (hits + shifts < 5) { + quality -= (5 - (hits + shifts)) * 10; + } + + if (quality < 0) { + quality = 0; + } + return quality; + } + + + static class CharsetRecog_2022JP extends CharsetRecog_2022 { + private byte[][] escapeSequences = { + {0x1b, 0x24, 0x28, 0x43}, // KS X 1001:1992 + {0x1b, 0x24, 0x28, 0x44}, // JIS X 212-1990 + {0x1b, 0x24, 0x40}, // JIS C 6226-1978 + {0x1b, 0x24, 0x41}, // GB 2312-80 + {0x1b, 0x24, 0x42}, // JIS X 208-1983 + {0x1b, 0x26, 0x40}, // JIS X 208 1990, 1997 + {0x1b, 0x28, 0x42}, // ASCII + {0x1b, 0x28, 0x48}, // JIS-Roman + {0x1b, 0x28, 0x49}, // Half-width katakana + {0x1b, 0x28, 0x4a}, // JIS-Roman + {0x1b, 0x2e, 0x41}, // ISO 8859-1 + {0x1b, 0x2e, 0x46} // ISO 8859-7 + }; + + String getName() { + return "ISO-2022-JP"; + } + + int match(CharsetDetector det) { + return match(det.fInputBytes, det.fInputLen, escapeSequences); + } + } + + static class CharsetRecog_2022KR extends CharsetRecog_2022 { + private byte[][] escapeSequences = { + {0x1b, 0x24, 0x29, 0x43} + }; + + String getName() { + return "ISO-2022-KR"; + } + + int match(CharsetDetector det) { + return match(det.fInputBytes, det.fInputLen, escapeSequences); + } + + } + + static class CharsetRecog_2022CN extends CharsetRecog_2022 { + private byte[][] escapeSequences = { + {0x1b, 0x24, 0x29, 0x41}, // GB 2312-80 + {0x1b, 0x24, 0x29, 0x47}, // CNS 11643-1992 Plane 1 + {0x1b, 0x24, 0x2A, 0x48}, // CNS 11643-1992 Plane 2 + {0x1b, 0x24, 0x29, 0x45}, // ISO-IR-165 + {0x1b, 0x24, 0x2B, 0x49}, // CNS 11643-1992 Plane 3 + {0x1b, 0x24, 0x2B, 0x4A}, // CNS 11643-1992 Plane 4 + {0x1b, 0x24, 0x2B, 0x4B}, // CNS 11643-1992 Plane 5 + {0x1b, 0x24, 0x2B, 0x4C}, // CNS 11643-1992 Plane 6 + {0x1b, 0x24, 0x2B, 0x4D}, // CNS 11643-1992 Plane 7 + {0x1b, 0x4e}, // SS2 + {0x1b, 0x4f}, // SS3 + }; + + String getName() { + return "ISO-2022-CN"; + } + + + int match(CharsetDetector det) { + return match(det.fInputBytes, det.fInputLen, escapeSequences); + } + } + +} + Added: tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_UTF8.java URL: http://svn.apache.org/viewvc/tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_UTF8.java?rev=1723223&view=auto ============================================================================== --- tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_UTF8.java (added) +++ tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_UTF8.java Wed Jan 6 03:50:50 2016 @@ -0,0 +1,99 @@ +/** + * ****************************************************************************** + * Copyright (C) 2005 - 2007, International Business Machines Corporation and * + * others. All Rights Reserved. * + * ****************************************************************************** + */ +package org.apache.tika.parser.txt; + +/** + * Charset recognizer for UTF-8 + * + * @internal + */ +class CharsetRecog_UTF8 extends CharsetRecognizer { + + String getName() { + return "UTF-8"; + } + + /* (non-Javadoc) + * @see com.ibm.icu.text.CharsetRecognizer#match(com.ibm.icu.text.CharsetDetector) + */ + int match(CharsetDetector det) { + boolean hasBOM = false; + int numValid = 0; + int numInvalid = 0; + byte input[] = det.fRawInput; + int i; + int trailBytes = 0; + int confidence; + + if (det.fRawLength >= 3 && + (input[0] & 0xFF) == 0xef && (input[1] & 0xFF) == 0xbb && (input[2] & 0xFF) == 0xbf) { + hasBOM = true; + } + + // Scan for multi-byte sequences + for (i = 0; i < det.fRawLength; i++) { + int b = input[i]; + if ((b & 0x80) == 0) { + continue; // ASCII + } + + // Hi bit on char found. Figure out how long the sequence should be + if ((b & 0x0e0) == 0x0c0) { + trailBytes = 1; + } else if ((b & 0x0f0) == 0x0e0) { + trailBytes = 2; + } else if ((b & 0x0f8) == 0xf0) { + trailBytes = 3; + } else { + numInvalid++; + if (numInvalid > 5) { + break; + } + trailBytes = 0; + } + + // Verify that we've got the right number of trail bytes in the sequence + for (; ; ) { + i++; + if (i >= det.fRawLength) { + break; + } + b = input[i]; + if ((b & 0xc0) != 0x080) { + numInvalid++; + break; + } + if (--trailBytes == 0) { + numValid++; + break; + } + } + + } + + // Cook up some sort of confidence score, based on presense of a BOM + // and the existence of valid and/or invalid multi-byte sequences. + confidence = 0; + if (hasBOM && numInvalid == 0) { + confidence = 100; + } else if (hasBOM && numValid > numInvalid * 10) { + confidence = 80; + } else if (numValid > 3 && numInvalid == 0) { + confidence = 100; + } else if (numValid > 0 && numInvalid == 0) { + confidence = 80; + } else if (numValid == 0 && numInvalid == 0) { + // Plain ASCII. + confidence = 10; + } else if (numValid > numInvalid * 10) { + // Probably corruput utf-8 data. Valid sequences aren't likely by chance. + confidence = 25; + } + return confidence; + } + +} Added: tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_Unicode.java URL: http://svn.apache.org/viewvc/tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_Unicode.java?rev=1723223&view=auto ============================================================================== --- tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_Unicode.java (added) +++ tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_Unicode.java Wed Jan 6 03:50:50 2016 @@ -0,0 +1,139 @@ +/* + ******************************************************************************* + * Copyright (C) 1996-2007, International Business Machines Corporation and * + * others. All Rights Reserved. * + ******************************************************************************* + * + */ +package org.apache.tika.parser.txt; + +/** + * This class matches UTF-16 and UTF-32, both big- and little-endian. The + * BOM will be used if it is present. + * + * @internal + */ +abstract class CharsetRecog_Unicode extends CharsetRecognizer { + + /* (non-Javadoc) + * @see com.ibm.icu.text.CharsetRecognizer#getName() + */ + abstract String getName(); + + /* (non-Javadoc) + * @see com.ibm.icu.text.CharsetRecognizer#match(com.ibm.icu.text.CharsetDetector) + */ + abstract int match(CharsetDetector det); + + static class CharsetRecog_UTF_16_BE extends CharsetRecog_Unicode { + String getName() { + return "UTF-16BE"; + } + + int match(CharsetDetector det) { + byte[] input = det.fRawInput; + + if (input.length >= 2 && ((input[0] & 0xFF) == 0xFE && (input[1] & 0xFF) == 0xFF)) { + return 100; + } + + // TODO: Do some statistics to check for unsigned UTF-16BE + return 0; + } + } + + static class CharsetRecog_UTF_16_LE extends CharsetRecog_Unicode { + String getName() { + return "UTF-16LE"; + } + + int match(CharsetDetector det) { + byte[] input = det.fRawInput; + + if (input.length >= 2 && ((input[0] & 0xFF) == 0xFF && (input[1] & 0xFF) == 0xFE)) { + // An LE BOM is present. + if (input.length >= 4 && input[2] == 0x00 && input[3] == 0x00) { + // It is probably UTF-32 LE, not UTF-16 + return 0; + } + return 100; + } + + // TODO: Do some statistics to check for unsigned UTF-16LE + return 0; + } + } + + static abstract class CharsetRecog_UTF_32 extends CharsetRecog_Unicode { + abstract int getChar(byte[] input, int index); + + abstract String getName(); + + int match(CharsetDetector det) { + byte[] input = det.fRawInput; + int limit = (det.fRawLength / 4) * 4; + int numValid = 0; + int numInvalid = 0; + boolean hasBOM = false; + int confidence = 0; + + if (limit == 0) { + return 0; + } + if (getChar(input, 0) == 0x0000FEFF) { + hasBOM = true; + } + + for (int i = 0; i < limit; i += 4) { + int ch = getChar(input, i); + + if (ch < 0 || ch >= 0x10FFFF || (ch >= 0xD800 && ch <= 0xDFFF)) { + numInvalid += 1; + } else { + numValid += 1; + } + } + + + // Cook up some sort of confidence score, based on presence of a BOM + // and the existence of valid and/or invalid multi-byte sequences. + if (hasBOM && numInvalid == 0) { + confidence = 100; + } else if (hasBOM && numValid > numInvalid * 10) { + confidence = 80; + } else if (numValid > 3 && numInvalid == 0) { + confidence = 100; + } else if (numValid > 0 && numInvalid == 0) { + confidence = 80; + } else if (numValid > numInvalid * 10) { + // Probably corrupt UTF-32BE data. Valid sequences aren't likely by chance. + confidence = 25; + } + + return confidence; + } + } + + static class CharsetRecog_UTF_32_BE extends CharsetRecog_UTF_32 { + int getChar(byte[] input, int index) { + return (input[index + 0] & 0xFF) << 24 | (input[index + 1] & 0xFF) << 16 | + (input[index + 2] & 0xFF) << 8 | (input[index + 3] & 0xFF); + } + + String getName() { + return "UTF-32BE"; + } + } + + + static class CharsetRecog_UTF_32_LE extends CharsetRecog_UTF_32 { + int getChar(byte[] input, int index) { + return (input[index + 3] & 0xFF) << 24 | (input[index + 2] & 0xFF) << 16 | + (input[index + 1] & 0xFF) << 8 | (input[index + 0] & 0xFF); + } + + String getName() { + return "UTF-32LE"; + } + } +} Added: tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_mbcs.java URL: http://svn.apache.org/viewvc/tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_mbcs.java?rev=1723223&view=auto ============================================================================== --- tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_mbcs.java (added) +++ tika/branches/2.x/tika-parser-modules/tika-text-module/src/main/java/org/apache/tika/parser/txt/CharsetRecog_mbcs.java Wed Jan 6 03:50:50 2016 @@ -0,0 +1,532 @@ +/* + **************************************************************************** + * Copyright (C) 2005-2008, International Business Machines Corporation and * + * others. All Rights Reserved. * + **************************************************************************** + * + */ +package org.apache.tika.parser.txt; + +import java.util.Arrays; + +/** + * CharsetRecognizer implemenation for Asian - double or multi-byte - charsets. + * Match is determined mostly by the input data adhering to the + * encoding scheme for the charset, and, optionally, + * frequency-of-occurence of characters. + * <p/> + * Instances of this class are singletons, one per encoding + * being recognized. They are created in the main + * CharsetDetector class and kept in the global list of available + * encodings to be checked. The specific encoding being recognized + * is determined by subclass. + * + * @internal + */ +abstract class CharsetRecog_mbcs extends CharsetRecognizer { + + /** + * Get the IANA name of this charset. + * + * @return the charset name. + */ + abstract String getName(); + + + /** + * Test the match of this charset with the input text data + * which is obtained via the CharsetDetector object. + * + * @param det The CharsetDetector, which contains the input text + * to be checked for being in this charset. + * @return Two values packed into one int (Damn java, anyhow) + * <br/> + * bits 0-7: the match confidence, ranging from 0-100 + * <br/> + * bits 8-15: The match reason, an enum-like value. + */ + int match(CharsetDetector det, int[] commonChars) { + int singleByteCharCount = 0; + int doubleByteCharCount = 0; + int commonCharCount = 0; + int badCharCount = 0; + int totalCharCount = 0; + int confidence = 0; + iteratedChar iter = new iteratedChar(); + + detectBlock: + { + for (iter.reset(); nextChar(iter, det); ) { + totalCharCount++; + if (iter.error) { + badCharCount++; + } else { + long cv = iter.charValue & 0xFFFFFFFFL; + + if (cv <= 0xff) { + singleByteCharCount++; + } else { + doubleByteCharCount++; + if (commonChars != null) { + // NOTE: This assumes that there are no 4-byte common chars. + if (Arrays.binarySearch(commonChars, (int) cv) >= 0) { + commonCharCount++; + } + } + } + } + if (badCharCount >= 2 && badCharCount * 5 >= doubleByteCharCount) { + // Bail out early if the byte data is not matching the encoding scheme. + break detectBlock; + } + } + + if (doubleByteCharCount <= 10 && badCharCount == 0) { + // Not many multi-byte chars. + if (doubleByteCharCount == 0 && totalCharCount < 10) { + // There weren't any multibyte sequences, and there was a low density of non-ASCII single bytes. + // We don't have enough data to have any confidence. + // Statistical analysis of single byte non-ASCII charcters would probably help here. + confidence = 0; + } else { + // ASCII or ISO file? It's probably not our encoding, + // but is not incompatible with our encoding, so don't give it a zero. + confidence = 10; + } + + break detectBlock; + } + + // + // No match if there are too many characters that don't fit the encoding scheme. + // (should we have zero tolerance for these?) + // + if (doubleByteCharCount < 20 * badCharCount) { + confidence = 0; + break detectBlock; + } + + if (commonChars == null) { + // We have no statistics on frequently occuring characters. + // Assess confidence purely on having a reasonable number of + // multi-byte characters (the more the better + confidence = 30 + doubleByteCharCount - 20 * badCharCount; + if (confidence > 100) { + confidence = 100; + } + } else { + // + // Frequency of occurence statistics exist. + // + double maxVal = Math.log((float) doubleByteCharCount / 4); + double scaleFactor = 90.0 / maxVal; + confidence = (int) (Math.log(commonCharCount + 1) * scaleFactor + 10); + confidence = Math.min(confidence, 100); + } + } // end of detectBlock: + + return confidence; + } + + /** + * Get the next character (however many bytes it is) from the input data + * Subclasses for specific charset encodings must implement this function + * to get characters according to the rules of their encoding scheme. + * <p/> + * This function is not a method of class iteratedChar only because + * that would require a lot of extra derived classes, which is awkward. + * + * @param it The iteratedChar "struct" into which the returned char is placed. + * @param det The charset detector, which is needed to get at the input byte data + * being iterated over. + * @return True if a character was returned, false at end of input. + */ + abstract boolean nextChar(iteratedChar it, CharsetDetector det); + + // "Character" iterated character class. + // Recognizers for specific mbcs encodings make their "characters" available + // by providing a nextChar() function that fills in an instance of iteratedChar + // with the next char from the input. + // The returned characters are not converted to Unicode, but remain as the raw + // bytes (concatenated into an int) from the codepage data. + // + // For Asian charsets, use the raw input rather than the input that has been + // stripped of markup. Detection only considers multi-byte chars, effectively + // stripping markup anyway, and double byte chars do occur in markup too. + // + static class iteratedChar { + int charValue = 0; // 1-4 bytes from the raw input data + int index = 0; + int nextIndex = 0; + boolean error = false; + boolean done = false; + + void reset() { + charValue = 0; + index = -1; + nextIndex = 0; + error = false; + done = false; + } + + int nextByte(CharsetDetector det) { + if (nextIndex >= det.fRawLength) { + done = true; + return -1; + } + int byteValue = (int) det.fRawInput[nextIndex++] & 0x00ff; + return byteValue; + } + } + + /** + * Shift-JIS charset recognizer. + */ + static class CharsetRecog_sjis extends CharsetRecog_mbcs { + static int[] commonChars = + // TODO: This set of data comes from the character frequency- + // of-occurence analysis tool. The data needs to be moved + // into a resource and loaded from there. + {0x8140, 0x8141, 0x8142, 0x8145, 0x815b, 0x8169, 0x816a, 0x8175, 0x8176, 0x82a0, + 0x82a2, 0x82a4, 0x82a9, 0x82aa, 0x82ab, 0x82ad, 0x82af, 0x82b1, 0x82b3, 0x82b5, + 0x82b7, 0x82bd, 0x82be, 0x82c1, 0x82c4, 0x82c5, 0x82c6, 0x82c8, 0x82c9, 0x82cc, + 0x82cd, 0x82dc, 0x82e0, 0x82e7, 0x82e8, 0x82e9, 0x82ea, 0x82f0, 0x82f1, 0x8341, + 0x8343, 0x834e, 0x834f, 0x8358, 0x835e, 0x8362, 0x8367, 0x8375, 0x8376, 0x8389, + 0x838a, 0x838b, 0x838d, 0x8393, 0x8e96, 0x93fa, 0x95aa}; + + boolean nextChar(iteratedChar it, CharsetDetector det) { + it.index = it.nextIndex; + it.error = false; + int firstByte; + firstByte = it.charValue = it.nextByte(det); + if (firstByte < 0) { + return false; + } + + if (firstByte <= 0x7f || (firstByte > 0xa0 && firstByte <= 0xdf)) { + return true; + } + + int secondByte = it.nextByte(det); + if (secondByte < 0) { + return false; + } + it.charValue = (firstByte << 8) | secondByte; + if (!((secondByte >= 0x40 && secondByte <= 0x7f) || (secondByte >= 0x80 && secondByte <= 0xff))) { + // Illegal second byte value. + it.error = true; + } + return true; + } + + int match(CharsetDetector det) { + return match(det, commonChars); + } + + String getName() { + return "Shift_JIS"; + } + + public String getLanguage() { + return "ja"; + } + + + } + + + /** + * Big5 charset recognizer. + */ + static class CharsetRecog_big5 extends CharsetRecog_mbcs { + static int[] commonChars = + // TODO: This set of data comes from the character frequency- + // of-occurence analysis tool. The data needs to be moved + // into a resource and loaded from there. + {0xa140, 0xa141, 0xa142, 0xa143, 0xa147, 0xa149, 0xa175, 0xa176, 0xa440, 0xa446, + 0xa447, 0xa448, 0xa451, 0xa454, 0xa457, 0xa464, 0xa46a, 0xa46c, 0xa477, 0xa4a3, + 0xa4a4, 0xa4a7, 0xa4c1, 0xa4ce, 0xa4d1, 0xa4df, 0xa4e8, 0xa4fd, 0xa540, 0xa548, + 0xa558, 0xa569, 0xa5cd, 0xa5e7, 0xa657, 0xa661, 0xa662, 0xa668, 0xa670, 0xa6a8, + 0xa6b3, 0xa6b9, 0xa6d3, 0xa6db, 0xa6e6, 0xa6f2, 0xa740, 0xa751, 0xa759, 0xa7da, + 0xa8a3, 0xa8a5, 0xa8ad, 0xa8d1, 0xa8d3, 0xa8e4, 0xa8fc, 0xa9c0, 0xa9d2, 0xa9f3, + 0xaa6b, 0xaaba, 0xaabe, 0xaacc, 0xaafc, 0xac47, 0xac4f, 0xacb0, 0xacd2, 0xad59, + 0xaec9, 0xafe0, 0xb0ea, 0xb16f, 0xb2b3, 0xb2c4, 0xb36f, 0xb44c, 0xb44e, 0xb54c, + 0xb5a5, 0xb5bd, 0xb5d0, 0xb5d8, 0xb671, 0xb7ed, 0xb867, 0xb944, 0xbad8, 0xbb44, + 0xbba1, 0xbdd1, 0xc2c4, 0xc3b9, 0xc440, 0xc45f}; + + boolean nextChar(iteratedChar it, CharsetDetector det) { + it.index = it.nextIndex; + it.error = false; + int firstByte; + firstByte = it.charValue = it.nextByte(det); + if (firstByte < 0) { + return false; + } + + if (firstByte <= 0x7f || firstByte == 0xff) { + // single byte character. + return true; + } + + int secondByte = it.nextByte(det); + if (secondByte < 0) { + return false; + } + it.charValue = (it.charValue << 8) | secondByte; + + if (secondByte < 0x40 || + secondByte == 0x7f || + secondByte == 0xff) { + it.error = true; + } + return true; + } + + int match(CharsetDetector det) { + return match(det, commonChars); + } + + String getName() { + return "Big5"; + } + + + public String getLanguage() { + return "zh"; + } + } + + + /** + * EUC charset recognizers. One abstract class that provides the common function + * for getting the next character according to the EUC encoding scheme, + * and nested derived classes for EUC_KR, EUC_JP, EUC_CN. + */ + abstract static class CharsetRecog_euc extends CharsetRecog_mbcs { + + /* + * (non-Javadoc) + * Get the next character value for EUC based encodings. + * Character "value" is simply the raw bytes that make up the character + * packed into an int. + */ + boolean nextChar(iteratedChar it, CharsetDetector det) { + it.index = it.nextIndex; + it.error = false; + int firstByte = 0; + int secondByte = 0; + int thirdByte = 0; + //int fourthByte = 0; + + buildChar: + { + firstByte = it.charValue = it.nextByte(det); + if (firstByte < 0) { + // Ran off the end of the input data + it.done = true; + break buildChar; + } + if (firstByte <= 0x8d) { + // single byte char + break buildChar; + } + + secondByte = it.nextByte(det); + it.charValue = (it.charValue << 8) | secondByte; + + if (firstByte >= 0xA1 && firstByte <= 0xfe) { + // Two byte Char + if (secondByte < 0xa1) { + it.error = true; + } + break buildChar; + } + if (firstByte == 0x8e) { + // Code Set 2. + // In EUC-JP, total char size is 2 bytes, only one byte of actual char value. + // In EUC-TW, total char size is 4 bytes, three bytes contribute to char value. + // We don't know which we've got. + // Treat it like EUC-JP. If the data really was EUC-TW, the following two + // bytes will look like a well formed 2 byte char. + if (secondByte < 0xa1) { + it.error = true; + } + break buildChar; + } + + if (firstByte == 0x8f) { + // Code set 3. + // Three byte total char size, two bytes of actual char value. + thirdByte = it.nextByte(det); + it.charValue = (it.charValue << 8) | thirdByte; + if (thirdByte < 0xa1) { + it.error = true; + } + } + } + + return (it.done == false); + } + + /** + * The charset recognize for EUC-JP. A singleton instance of this class + * is created and kept by the public CharsetDetector class + */ + static class CharsetRecog_euc_jp extends CharsetRecog_euc { + static int[] commonChars = + // TODO: This set of data comes from the character frequency- + // of-occurence analysis tool. The data needs to be moved + // into a resource and loaded from there. + {0xa1a1, 0xa1a2, 0xa1a3, 0xa1a6, 0xa1bc, 0xa1ca, 0xa1cb, 0xa1d6, 0xa1d7, 0xa4a2, + 0xa4a4, 0xa4a6, 0xa4a8, 0xa4aa, 0xa4ab, 0xa4ac, 0xa4ad, 0xa4af, 0xa4b1, 0xa4b3, + 0xa4b5, 0xa4b7, 0xa4b9, 0xa4bb, 0xa4bd, 0xa4bf, 0xa4c0, 0xa4c1, 0xa4c3, 0xa4c4, + 0xa4c6, 0xa4c7, 0xa4c8, 0xa4c9, 0xa4ca, 0xa4cb, 0xa4ce, 0xa4cf, 0xa4d0, 0xa4de, + 0xa4df, 0xa4e1, 0xa4e2, 0xa4e4, 0xa4e8, 0xa4e9, 0xa4ea, 0xa4eb, 0xa4ec, 0xa4ef, + 0xa4f2, 0xa4f3, 0xa5a2, 0xa5a3, 0xa5a4, 0xa5a6, 0xa5a7, 0xa5aa, 0xa5ad, 0xa5af, + 0xa5b0, 0xa5b3, 0xa5b5, 0xa5b7, 0xa5b8, 0xa5b9, 0xa5bf, 0xa5c3, 0xa5c6, 0xa5c7, + 0xa5c8, 0xa5c9, 0xa5cb, 0xa5d0, 0xa5d5, 0xa5d6, 0xa5d7, 0xa5de, 0xa5e0, 0xa5e1, + 0xa5e5, 0xa5e9, 0xa5ea, 0xa5eb, 0xa5ec, 0xa5ed, 0xa5f3, 0xb8a9, 0xb9d4, 0xbaee, + 0xbbc8, 0xbef0, 0xbfb7, 0xc4ea, 0xc6fc, 0xc7bd, 0xcab8, 0xcaf3, 0xcbdc, 0xcdd1}; + + String getName() { + return "EUC-JP"; + } + + int match(CharsetDetector det) { + return match(det, commonChars); + } + + public String getLanguage() { + return "ja"; + } + } + + /** + * The charset recognize for EUC-KR. A singleton instance of this class + * is created and kept by the public CharsetDetector class + */ + static class CharsetRecog_euc_kr extends CharsetRecog_euc { + static int[] commonChars = + // TODO: This set of data comes from the character frequency- + // of-occurence analysis tool. The data needs to be moved + // into a resource and loaded from there. + {0xb0a1, 0xb0b3, 0xb0c5, 0xb0cd, 0xb0d4, 0xb0e6, 0xb0ed, 0xb0f8, 0xb0fa, 0xb0fc, + 0xb1b8, 0xb1b9, 0xb1c7, 0xb1d7, 0xb1e2, 0xb3aa, 0xb3bb, 0xb4c2, 0xb4cf, 0xb4d9, + 0xb4eb, 0xb5a5, 0xb5b5, 0xb5bf, 0xb5c7, 0xb5e9, 0xb6f3, 0xb7af, 0xb7c2, 0xb7ce, + 0xb8a6, 0xb8ae, 0xb8b6, 0xb8b8, 0xb8bb, 0xb8e9, 0xb9ab, 0xb9ae, 0xb9cc, 0xb9ce, + 0xb9fd, 0xbab8, 0xbace, 0xbad0, 0xbaf1, 0xbbe7, 0xbbf3, 0xbbfd, 0xbcad, 0xbcba, + 0xbcd2, 0xbcf6, 0xbdba, 0xbdc0, 0xbdc3, 0xbdc5, 0xbec6, 0xbec8, 0xbedf, 0xbeee, + 0xbef8, 0xbefa, 0xbfa1, 0xbfa9, 0xbfc0, 0xbfe4, 0xbfeb, 0xbfec, 0xbff8, 0xc0a7, + 0xc0af, 0xc0b8, 0xc0ba, 0xc0bb, 0xc0bd, 0xc0c7, 0xc0cc, 0xc0ce, 0xc0cf, 0xc0d6, + 0xc0da, 0xc0e5, 0xc0fb, 0xc0fc, 0xc1a4, 0xc1a6, 0xc1b6, 0xc1d6, 0xc1df, 0xc1f6, + 0xc1f8, 0xc4a1, 0xc5cd, 0xc6ae, 0xc7cf, 0xc7d1, 0xc7d2, 0xc7d8, 0xc7e5, 0xc8ad}; + + String getName() { + return "EUC-KR"; + } + + int match(CharsetDetector det) { + return match(det, commonChars); + } + + public String getLanguage() { + return "ko"; + } + } + } + + /** + * GB-18030 recognizer. Uses simplified Chinese statistics. + */ + static class CharsetRecog_gb_18030 extends CharsetRecog_mbcs { + + static int[] commonChars = + // TODO: This set of data comes from the character frequency- + // of-occurence analysis tool. The data needs to be moved + // into a resource and loaded from there. + {0xa1a1, 0xa1a2, 0xa1a3, 0xa1a4, 0xa1b0, 0xa1b1, 0xa1f1, 0xa1f3, 0xa3a1, 0xa3ac, + 0xa3ba, 0xb1a8, 0xb1b8, 0xb1be, 0xb2bb, 0xb3c9, 0xb3f6, 0xb4f3, 0xb5bd, 0xb5c4, + 0xb5e3, 0xb6af, 0xb6d4, 0xb6e0, 0xb7a2, 0xb7a8, 0xb7bd, 0xb7d6, 0xb7dd, 0xb8b4, + 0xb8df, 0xb8f6, 0xb9ab, 0xb9c9, 0xb9d8, 0xb9fa, 0xb9fd, 0xbacd, 0xbba7, 0xbbd6, + 0xbbe1, 0xbbfa, 0xbcbc, 0xbcdb, 0xbcfe, 0xbdcc, 0xbecd, 0xbedd, 0xbfb4, 0xbfc6, + 0xbfc9, 0xc0b4, 0xc0ed, 0xc1cb, 0xc2db, 0xc3c7, 0xc4dc, 0xc4ea, 0xc5cc, 0xc6f7, + 0xc7f8, 0xc8ab, 0xc8cb, 0xc8d5, 0xc8e7, 0xc9cf, 0xc9fa, 0xcab1, 0xcab5, 0xcac7, + 0xcad0, 0xcad6, 0xcaf5, 0xcafd, 0xccec, 0xcdf8, 0xceaa, 0xcec4, 0xced2, 0xcee5, + 0xcfb5, 0xcfc2, 0xcfd6, 0xd0c2, 0xd0c5, 0xd0d0, 0xd0d4, 0xd1a7, 0xd2aa, 0xd2b2, + 0xd2b5, 0xd2bb, 0xd2d4, 0xd3c3, 0xd3d0, 0xd3fd, 0xd4c2, 0xd4da, 0xd5e2, 0xd6d0}; + + /* + * (non-Javadoc) + * Get the next character value for EUC based encodings. + * Character "value" is simply the raw bytes that make up the character + * packed into an int. + */ + boolean nextChar(iteratedChar it, CharsetDetector det) { + it.index = it.nextIndex; + it.error = false; + int firstByte = 0; + int secondByte = 0; + int thirdByte = 0; + int fourthByte = 0; + + buildChar: + { + firstByte = it.charValue = it.nextByte(det); + + if (firstByte < 0) { + // Ran off the end of the input data + it.done = true; + break buildChar; + } + + if (firstByte <= 0x80) { + // single byte char + break buildChar; + } + + secondByte = it.nextByte(det); + it.charValue = (it.charValue << 8) | secondByte; + + if (firstByte >= 0x81 && firstByte <= 0xFE) { + // Two byte Char + if ((secondByte >= 0x40 && secondByte <= 0x7E) || (secondByte >= 80 && secondByte <= 0xFE)) { + break buildChar; + } + + // Four byte char + if (secondByte >= 0x30 && secondByte <= 0x39) { + thirdByte = it.nextByte(det); + + if (thirdByte >= 0x81 && thirdByte <= 0xFE) { + fourthByte = it.nextByte(det); + + if (fourthByte >= 0x30 && fourthByte <= 0x39) { + it.charValue = (it.charValue << 16) | (thirdByte << 8) | fourthByte; + break buildChar; + } + } + } + + it.error = true; + break buildChar; + } + } + + return (it.done == false); + } + + String getName() { + return "GB18030"; + } + + int match(CharsetDetector det) { + return match(det, commonChars); + } + + public String getLanguage() { + return "zh"; + } + } + + +}
