Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.google.ratel.deps.io.input; import java.io.BufferedInputStream; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.Reader; import java.io.StringReader; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.text.MessageFormat; import java.util.Locale; import java.util.regex.Matcher; import java.util.regex.Pattern; import com.google.ratel.deps.io.ByteOrderMark; /** * Character stream that handles all the necessary Voodo to figure out the * charset encoding of the XML document within the stream. * <p> * IMPORTANT: This class is not related in any way to the org.xml.sax.XMLReader. * This one IS a character stream. * <p> * All this has to be done without consuming characters from the stream, if not * the XML parser will not recognized the document as a valid XML. This is not * 100% true, but it's close enough (UTF-8 BOM is not handled by all parsers * right now, XmlStreamReader handles it and things work in all parsers). * <p> * The XmlStreamReader class handles the charset encoding of XML documents in * Files, raw streams and HTTP streams by offering a wide set of constructors. * <p> * By default the charset encoding detection is lenient, the constructor with * the lenient flag can be used for an script (following HTTP MIME and XML * specifications). All this is nicely explained by Mark Pilgrim in his blog, <a * href="http://diveintomark.org/archives/2004/02/13/xml-media-types"> * Determining the character encoding of a feed</a>. * <p> * Originally developed for <a href="http://rome.dev.java.net">ROME</a> under * Apache License 2.0. * * @version $Id: XmlStreamReader.java 1346400 2012-06-05 14:48:01Z ggregory $ * @see org.apache.commons.io.output.XmlStreamWriter * @since 2.0 */ public class XmlStreamReader extends Reader { private static final int BUFFER_SIZE = 4096; private static final String UTF_8 = "UTF-8"; private static final String US_ASCII = "US-ASCII"; private static final String UTF_16BE = "UTF-16BE"; private static final String UTF_16LE = "UTF-16LE"; private static final String UTF_32BE = "UTF-32BE"; private static final String UTF_32LE = "UTF-32LE"; private static final String UTF_16 = "UTF-16"; private static final String UTF_32 = "UTF-32"; private static final String EBCDIC = "CP1047"; private static final ByteOrderMark[] BOMS = new ByteOrderMark[] { ByteOrderMark.UTF_8, ByteOrderMark.UTF_16BE, ByteOrderMark.UTF_16LE, ByteOrderMark.UTF_32BE, ByteOrderMark.UTF_32LE }; // UTF_16LE and UTF_32LE have the same two starting BOM bytes. private static final ByteOrderMark[] XML_GUESS_BYTES = new ByteOrderMark[] { new ByteOrderMark(UTF_8, 0x3C, 0x3F, 0x78, 0x6D), new ByteOrderMark(UTF_16BE, 0x00, 0x3C, 0x00, 0x3F), new ByteOrderMark(UTF_16LE, 0x3C, 0x00, 0x3F, 0x00), new ByteOrderMark(UTF_32BE, 0x00, 0x00, 0x00, 0x3C, 0x00, 0x00, 0x00, 0x3F, 0x00, 0x00, 0x00, 0x78, 0x00, 0x00, 0x00, 0x6D), new ByteOrderMark(UTF_32LE, 0x3C, 0x00, 0x00, 0x00, 0x3F, 0x00, 0x00, 0x00, 0x78, 0x00, 0x00, 0x00, 0x6D, 0x00, 0x00, 0x00), new ByteOrderMark(EBCDIC, 0x4C, 0x6F, 0xA7, 0x94) }; private final Reader reader; private final String encoding; private final String defaultEncoding; /** * Returns the default encoding to use if none is set in HTTP content-type, * XML prolog and the rules based on content-type are not adequate. * <p> * If it is NULL the content-type based rules are used. * * @return the default encoding to use. */ public String getDefaultEncoding() { return defaultEncoding; } /** * Creates a Reader for a File. * <p> * It looks for the UTF-8 BOM first, if none sniffs the XML prolog charset, * if this is also missing defaults to UTF-8. * <p> * It does a lenient charset encoding detection, check the constructor with * the lenient parameter for details. * * @param file File to create a Reader from. * @throws IOException thrown if there is a problem reading the file. */ public XmlStreamReader(File file) throws IOException { this(new FileInputStream(file)); } /** * Creates a Reader for a raw InputStream. * <p> * It follows the same logic used for files. * <p> * It does a lenient charset encoding detection, check the constructor with * the lenient parameter for details. * * @param is InputStream to create a Reader from. * @throws IOException thrown if there is a problem reading the stream. */ public XmlStreamReader(InputStream is) throws IOException { this(is, true); } /** * Creates a Reader for a raw InputStream. * <p> * It follows the same logic used for files. * <p> * If lenient detection is indicated and the detection above fails as per * specifications it then attempts the following: * <p> * If the content type was 'text/html' it replaces it with 'text/xml' and * tries the detection again. * <p> * Else if the XML prolog had a charset encoding that encoding is used. * <p> * Else if the content type had a charset encoding that encoding is used. * <p> * Else 'UTF-8' is used. * <p> * If lenient detection is indicated an XmlStreamReaderException is never * thrown. * * @param is InputStream to create a Reader from. * @param lenient indicates if the charset encoding detection should be * relaxed. * @throws IOException thrown if there is a problem reading the stream. * @throws XmlStreamReaderException thrown if the charset encoding could not * be determined according to the specs. */ public XmlStreamReader(InputStream is, boolean lenient) throws IOException { this(is, lenient, null); } /** * Creates a Reader for a raw InputStream. * <p> * It follows the same logic used for files. * <p> * If lenient detection is indicated and the detection above fails as per * specifications it then attempts the following: * <p> * If the content type was 'text/html' it replaces it with 'text/xml' and * tries the detection again. * <p> * Else if the XML prolog had a charset encoding that encoding is used. * <p> * Else if the content type had a charset encoding that encoding is used. * <p> * Else 'UTF-8' is used. * <p> * If lenient detection is indicated an XmlStreamReaderException is never * thrown. * * @param is InputStream to create a Reader from. * @param lenient indicates if the charset encoding detection should be * relaxed. * @param defaultEncoding The default encoding * @throws IOException thrown if there is a problem reading the stream. * @throws XmlStreamReaderException thrown if the charset encoding could not * be determined according to the specs. */ public XmlStreamReader(InputStream is, boolean lenient, String defaultEncoding) throws IOException { this.defaultEncoding = defaultEncoding; BOMInputStream bom = new BOMInputStream(new BufferedInputStream(is, BUFFER_SIZE), false, BOMS); BOMInputStream pis = new BOMInputStream(bom, true, XML_GUESS_BYTES); this.encoding = doRawStream(bom, pis, lenient); this.reader = new InputStreamReader(pis, encoding); } /** * Creates a Reader using the InputStream of a URL. * <p> * If the URL is not of type HTTP and there is not 'content-type' header in * the fetched data it uses the same logic used for Files. * <p> * If the URL is a HTTP Url or there is a 'content-type' header in the * fetched data it uses the same logic used for an InputStream with * content-type. * <p> * It does a lenient charset encoding detection, check the constructor with * the lenient parameter for details. * * @param url URL to create a Reader from. * @throws IOException thrown if there is a problem reading the stream of * the URL. */ public XmlStreamReader(URL url) throws IOException { this(url.openConnection(), null); } /** * Creates a Reader using the InputStream of a URLConnection. * <p> * If the URLConnection is not of type HttpURLConnection and there is not * 'content-type' header in the fetched data it uses the same logic used for * files. * <p> * If the URLConnection is a HTTP Url or there is a 'content-type' header in * the fetched data it uses the same logic used for an InputStream with * content-type. * <p> * It does a lenient charset encoding detection, check the constructor with * the lenient parameter for details. * * @param conn URLConnection to create a Reader from. * @param defaultEncoding The default encoding * @throws IOException thrown if there is a problem reading the stream of * the URLConnection. */ public XmlStreamReader(URLConnection conn, String defaultEncoding) throws IOException { this.defaultEncoding = defaultEncoding; boolean lenient = true; String contentType = conn.getContentType(); InputStream is = conn.getInputStream(); BOMInputStream bom = new BOMInputStream(new BufferedInputStream(is, BUFFER_SIZE), false, BOMS); BOMInputStream pis = new BOMInputStream(bom, true, XML_GUESS_BYTES); if (conn instanceof HttpURLConnection || contentType != null) { this.encoding = doHttpStream(bom, pis, contentType, lenient); } else { this.encoding = doRawStream(bom, pis, lenient); } this.reader = new InputStreamReader(pis, encoding); } /** * Creates a Reader using an InputStream an the associated content-type * header. * <p> * First it checks if the stream has BOM. If there is not BOM checks the * content-type encoding. If there is not content-type encoding checks the * XML prolog encoding. If there is not XML prolog encoding uses the default * encoding mandated by the content-type MIME type. * <p> * It does a lenient charset encoding detection, check the constructor with * the lenient parameter for details. * * @param is InputStream to create the reader from. * @param httpContentType content-type header to use for the resolution of * the charset encoding. * @throws IOException thrown if there is a problem reading the file. */ public XmlStreamReader(InputStream is, String httpContentType) throws IOException { this(is, httpContentType, true); } /** * Creates a Reader using an InputStream an the associated content-type * header. This constructor is lenient regarding the encoding detection. * <p> * First it checks if the stream has BOM. If there is not BOM checks the * content-type encoding. If there is not content-type encoding checks the * XML prolog encoding. If there is not XML prolog encoding uses the default * encoding mandated by the content-type MIME type. * <p> * If lenient detection is indicated and the detection above fails as per * specifications it then attempts the following: * <p> * If the content type was 'text/html' it replaces it with 'text/xml' and * tries the detection again. * <p> * Else if the XML prolog had a charset encoding that encoding is used. * <p> * Else if the content type had a charset encoding that encoding is used. * <p> * Else 'UTF-8' is used. * <p> * If lenient detection is indicated an XmlStreamReaderException is never * thrown. * * @param is InputStream to create the reader from. * @param httpContentType content-type header to use for the resolution of * the charset encoding. * @param lenient indicates if the charset encoding detection should be * relaxed. * @param defaultEncoding The default encoding * @throws IOException thrown if there is a problem reading the file. * @throws XmlStreamReaderException thrown if the charset encoding could not * be determined according to the specs. */ public XmlStreamReader(InputStream is, String httpContentType, boolean lenient, String defaultEncoding) throws IOException { this.defaultEncoding = defaultEncoding; BOMInputStream bom = new BOMInputStream(new BufferedInputStream(is, BUFFER_SIZE), false, BOMS); BOMInputStream pis = new BOMInputStream(bom, true, XML_GUESS_BYTES); this.encoding = doHttpStream(bom, pis, httpContentType, lenient); this.reader = new InputStreamReader(pis, encoding); } /** * Creates a Reader using an InputStream an the associated content-type * header. This constructor is lenient regarding the encoding detection. * <p> * First it checks if the stream has BOM. If there is not BOM checks the * content-type encoding. If there is not content-type encoding checks the * XML prolog encoding. If there is not XML prolog encoding uses the default * encoding mandated by the content-type MIME type. * <p> * If lenient detection is indicated and the detection above fails as per * specifications it then attempts the following: * <p> * If the content type was 'text/html' it replaces it with 'text/xml' and * tries the detection again. * <p> * Else if the XML prolog had a charset encoding that encoding is used. * <p> * Else if the content type had a charset encoding that encoding is used. * <p> * Else 'UTF-8' is used. * <p> * If lenient detection is indicated an XmlStreamReaderException is never * thrown. * * @param is InputStream to create the reader from. * @param httpContentType content-type header to use for the resolution of * the charset encoding. * @param lenient indicates if the charset encoding detection should be * relaxed. * @throws IOException thrown if there is a problem reading the file. * @throws XmlStreamReaderException thrown if the charset encoding could not * be determined according to the specs. */ public XmlStreamReader(InputStream is, String httpContentType, boolean lenient) throws IOException { this(is, httpContentType, lenient, null); } /** * Returns the charset encoding of the XmlStreamReader. * * @return charset encoding. */ public String getEncoding() { return encoding; } /** * Invokes the underlying reader's <code>read(char[], int, int)</code> method. * @param buf the buffer to read the characters into * @param offset The start offset * @param len The number of bytes to read * @return the number of characters read or -1 if the end of stream * @throws IOException if an I/O error occurs */ @Override public int read(char[] buf, int offset, int len) throws IOException { return reader.read(buf, offset, len); } /** * Closes the XmlStreamReader stream. * * @throws IOException thrown if there was a problem closing the stream. */ @Override public void close() throws IOException { reader.close(); } /** * Process the raw stream. * * @param bom BOMInputStream to detect byte order marks * @param pis BOMInputStream to guess XML encoding * @param lenient indicates if the charset encoding detection should be * relaxed. * @return the encoding to be used * @throws IOException thrown if there is a problem reading the stream. */ private String doRawStream(BOMInputStream bom, BOMInputStream pis, boolean lenient) throws IOException { String bomEnc = bom.getBOMCharsetName(); String xmlGuessEnc = pis.getBOMCharsetName(); String xmlEnc = getXmlProlog(pis, xmlGuessEnc); try { return calculateRawEncoding(bomEnc, xmlGuessEnc, xmlEnc); } catch (XmlStreamReaderException ex) { if (lenient) { return doLenientDetection(null, ex); } else { throw ex; } } } /** * Process a HTTP stream. * * @param bom BOMInputStream to detect byte order marks * @param pis BOMInputStream to guess XML encoding * @param httpContentType The HTTP content type * @param lenient indicates if the charset encoding detection should be * relaxed. * @return the encoding to be used * @throws IOException thrown if there is a problem reading the stream. */ private String doHttpStream(BOMInputStream bom, BOMInputStream pis, String httpContentType, boolean lenient) throws IOException { String bomEnc = bom.getBOMCharsetName(); String xmlGuessEnc = pis.getBOMCharsetName(); String xmlEnc = getXmlProlog(pis, xmlGuessEnc); try { return calculateHttpEncoding(httpContentType, bomEnc, xmlGuessEnc, xmlEnc, lenient); } catch (XmlStreamReaderException ex) { if (lenient) { return doLenientDetection(httpContentType, ex); } else { throw ex; } } } /** * Do lenient detection. * * @param httpContentType content-type header to use for the resolution of * the charset encoding. * @param ex The thrown exception * @return the encoding * @throws IOException thrown if there is a problem reading the stream. */ private String doLenientDetection(String httpContentType, XmlStreamReaderException ex) throws IOException { if (httpContentType != null && httpContentType.startsWith("text/html")) { httpContentType = httpContentType.substring("text/html".length()); httpContentType = "text/xml" + httpContentType; try { return calculateHttpEncoding(httpContentType, ex.getBomEncoding(), ex.getXmlGuessEncoding(), ex.getXmlEncoding(), true); } catch (XmlStreamReaderException ex2) { ex = ex2; } } String encoding = ex.getXmlEncoding(); if (encoding == null) { encoding = ex.getContentTypeEncoding(); } if (encoding == null) { encoding = defaultEncoding == null ? UTF_8 : defaultEncoding; } return encoding; } /** * Calculate the raw encoding. * * @param bomEnc BOM encoding * @param xmlGuessEnc XML Guess encoding * @param xmlEnc XML encoding * @return the raw encoding * @throws IOException thrown if there is a problem reading the stream. */ String calculateRawEncoding(String bomEnc, String xmlGuessEnc, String xmlEnc) throws IOException { // BOM is Null if (bomEnc == null) { if (xmlGuessEnc == null || xmlEnc == null) { return defaultEncoding == null ? UTF_8 : defaultEncoding; } if (xmlEnc.equals(UTF_16) && (xmlGuessEnc.equals(UTF_16BE) || xmlGuessEnc.equals(UTF_16LE))) { return xmlGuessEnc; } return xmlEnc; } // BOM is UTF-8 if (bomEnc.equals(UTF_8)) { if (xmlGuessEnc != null && !xmlGuessEnc.equals(UTF_8)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } if (xmlEnc != null && !xmlEnc.equals(UTF_8)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } return bomEnc; } // BOM is UTF-16BE or UTF-16LE if (bomEnc.equals(UTF_16BE) || bomEnc.equals(UTF_16LE)) { if (xmlGuessEnc != null && !xmlGuessEnc.equals(bomEnc)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } if (xmlEnc != null && !xmlEnc.equals(UTF_16) && !xmlEnc.equals(bomEnc)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } return bomEnc; } // BOM is UTF-32BE or UTF-32LE if (bomEnc.equals(UTF_32BE) || bomEnc.equals(UTF_32LE)) { if (xmlGuessEnc != null && !xmlGuessEnc.equals(bomEnc)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } if (xmlEnc != null && !xmlEnc.equals(UTF_32) && !xmlEnc.equals(bomEnc)) { String msg = MessageFormat.format(RAW_EX_1, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } return bomEnc; } // BOM is something else String msg = MessageFormat.format(RAW_EX_2, new Object[] { bomEnc, xmlGuessEnc, xmlEnc }); throw new XmlStreamReaderException(msg, bomEnc, xmlGuessEnc, xmlEnc); } /** * Calculate the HTTP encoding. * * @param httpContentType The HTTP content type * @param bomEnc BOM encoding * @param xmlGuessEnc XML Guess encoding * @param xmlEnc XML encoding * @param lenient indicates if the charset encoding detection should be * relaxed. * @return the HTTP encoding * @throws IOException thrown if there is a problem reading the stream. */ String calculateHttpEncoding(String httpContentType, String bomEnc, String xmlGuessEnc, String xmlEnc, boolean lenient) throws IOException { // Lenient and has XML encoding if (lenient && xmlEnc != null) { return xmlEnc; } // Determine mime/encoding content types from HTTP Content Type String cTMime = getContentTypeMime(httpContentType); String cTEnc = getContentTypeEncoding(httpContentType); boolean appXml = isAppXml(cTMime); boolean textXml = isTextXml(cTMime); // Mime type NOT "application/xml" or "text/xml" if (!appXml && !textXml) { String msg = MessageFormat.format(HTTP_EX_3, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); throw new XmlStreamReaderException(msg, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); } // No content type encoding if (cTEnc == null) { if (appXml) { return calculateRawEncoding(bomEnc, xmlGuessEnc, xmlEnc); } else { return defaultEncoding == null ? US_ASCII : defaultEncoding; } } // UTF-16BE or UTF-16LE content type encoding if (cTEnc.equals(UTF_16BE) || cTEnc.equals(UTF_16LE)) { if (bomEnc != null) { String msg = MessageFormat.format(HTTP_EX_1, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); throw new XmlStreamReaderException(msg, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); } return cTEnc; } // UTF-16 content type encoding if (cTEnc.equals(UTF_16)) { if (bomEnc != null && bomEnc.startsWith(UTF_16)) { return bomEnc; } String msg = MessageFormat.format(HTTP_EX_2, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); throw new XmlStreamReaderException(msg, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); } // UTF-32BE or UTF-132E content type encoding if (cTEnc.equals(UTF_32BE) || cTEnc.equals(UTF_32LE)) { if (bomEnc != null) { String msg = MessageFormat.format(HTTP_EX_1, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); throw new XmlStreamReaderException(msg, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); } return cTEnc; } // UTF-32 content type encoding if (cTEnc.equals(UTF_32)) { if (bomEnc != null && bomEnc.startsWith(UTF_32)) { return bomEnc; } String msg = MessageFormat.format(HTTP_EX_2, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); throw new XmlStreamReaderException(msg, cTMime, cTEnc, bomEnc, xmlGuessEnc, xmlEnc); } return cTEnc; } /** * Returns MIME type or NULL if httpContentType is NULL. * * @param httpContentType the HTTP content type * @return The mime content type */ static String getContentTypeMime(String httpContentType) { String mime = null; if (httpContentType != null) { int i = httpContentType.indexOf(";"); if (i >= 0) { mime = httpContentType.substring(0, i); } else { mime = httpContentType; } mime = mime.trim(); } return mime; } private static final Pattern CHARSET_PATTERN = Pattern.compile("charset=[\"']?([.[^; \"']]*)[\"']?"); /** * Returns charset parameter value, NULL if not present, NULL if * httpContentType is NULL. * * @param httpContentType the HTTP content type * @return The content type encoding (upcased) */ static String getContentTypeEncoding(String httpContentType) { String encoding = null; if (httpContentType != null) { int i = httpContentType.indexOf(";"); if (i > -1) { String postMime = httpContentType.substring(i + 1); Matcher m = CHARSET_PATTERN.matcher(postMime); encoding = m.find() ? m.group(1) : null; encoding = encoding != null ? encoding.toUpperCase(Locale.US) : null; } } return encoding; } public static final Pattern ENCODING_PATTERN = Pattern .compile("<\\?xml.*encoding[\\s]*=[\\s]*((?:\".[^\"]*\")|(?:'.[^']*'))", Pattern.MULTILINE); /** * Returns the encoding declared in the <?xml encoding=...?>, NULL if none. * * @param is InputStream to create the reader from. * @param guessedEnc guessed encoding * @return the encoding declared in the <?xml encoding=...?> * @throws IOException thrown if there is a problem reading the stream. */ private static String getXmlProlog(InputStream is, String guessedEnc) throws IOException { String encoding = null; if (guessedEnc != null) { byte[] bytes = new byte[BUFFER_SIZE]; is.mark(BUFFER_SIZE); int offset = 0; int max = BUFFER_SIZE; int c = is.read(bytes, offset, max); int firstGT = -1; String xmlProlog = null; while (c != -1 && firstGT == -1 && offset < BUFFER_SIZE) { offset += c; max -= c; c = is.read(bytes, offset, max); xmlProlog = new String(bytes, 0, offset, guessedEnc); firstGT = xmlProlog.indexOf('>'); } if (firstGT == -1) { if (c == -1) { throw new IOException("Unexpected end of XML stream"); } else { throw new IOException("XML prolog or ROOT element not found on first " + offset + " bytes"); } } int bytesRead = offset; if (bytesRead > 0) { is.reset(); BufferedReader bReader = new BufferedReader(new StringReader(xmlProlog.substring(0, firstGT + 1))); StringBuffer prolog = new StringBuffer(); String line = bReader.readLine(); while (line != null) { prolog.append(line); line = bReader.readLine(); } Matcher m = ENCODING_PATTERN.matcher(prolog); if (m.find()) { encoding = m.group(1).toUpperCase(); encoding = encoding.substring(1, encoding.length() - 1); } } } return encoding; } /** * Indicates if the MIME type belongs to the APPLICATION XML family. * * @param mime The mime type * @return true if the mime type belongs to the APPLICATION XML family, * otherwise false */ static boolean isAppXml(String mime) { return mime != null && (mime.equals("application/xml") || mime.equals("application/xml-dtd") || mime.equals("application/xml-external-parsed-entity") || mime.startsWith("application/") && mime.endsWith("+xml")); } /** * Indicates if the MIME type belongs to the TEXT XML family. * * @param mime The mime type * @return true if the mime type belongs to the TEXT XML family, * otherwise false */ static boolean isTextXml(String mime) { return mime != null && (mime.equals("text/xml") || mime.equals("text/xml-external-parsed-entity") || mime.startsWith("text/") && mime.endsWith("+xml")); } private static final String RAW_EX_1 = "Invalid encoding, BOM [{0}] XML guess [{1}] XML prolog [{2}] encoding mismatch"; private static final String RAW_EX_2 = "Invalid encoding, BOM [{0}] XML guess [{1}] XML prolog [{2}] unknown BOM"; private static final String HTTP_EX_1 = "Invalid encoding, CT-MIME [{0}] CT-Enc [{1}] BOM [{2}] XML guess [{3}] XML prolog [{4}], BOM must be NULL"; private static final String HTTP_EX_2 = "Invalid encoding, CT-MIME [{0}] CT-Enc [{1}] BOM [{2}] XML guess [{3}] XML prolog [{4}], encoding mismatch"; private static final String HTTP_EX_3 = "Invalid encoding, CT-MIME [{0}] CT-Enc [{1}] BOM [{2}] XML guess [{3}] XML prolog [{4}], Invalid MIME"; }