| /* |
| * The Apache Software License, Version 1.1 |
| * |
| * |
| * Copyright (c) 1999 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Xerces" and "Apache Software Foundation" must |
| * not be used to endorse or promote products derived from this |
| * software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * nor may "Apache" appear in their name, without prior written |
| * permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation and was |
| * originally based on software copyright (c) 1999, International |
| * Business Machines, Inc., http://www.apache.org. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| |
| package org.apache.xerces.readers; |
| |
| import org.apache.xerces.framework.XMLErrorReporter; |
| import org.apache.xerces.utils.ChunkyByteArray; |
| import org.apache.xerces.utils.StringPool; |
| import java.util.Stack; |
| |
| /** |
| * Abstract base class for encoding recognizers. |
| * |
| * When we encounter an external entity, including the document entity, |
| * and do not know what the encoding of the underlying byte stream is, |
| * we need to look at the contents of the stream to find out. We do this |
| * by asking a set of "recognizers" to look at the stream data and if |
| * the recognizer can understand the encoding it will try to read an |
| * XML or text declaration, if present, and construct the appropriate |
| * reader for that encoding. The recognizer subclasses will typically |
| * use the prescanXMLDeclOrTextDecl() method if the stream looks like |
| * it does begin with such a declaration using a temporary reader that |
| * can support the calls needed to scan through the encoding declaration. |
| */ |
| public abstract class XMLDeclRecognizer { |
| |
| /** |
| * Register the standard recognizers. |
| * |
| * @param recognizerStack The stack of recognizers used by the parser. |
| */ |
| public static void registerDefaultRecognizers(Stack recognizerStack) { |
| recognizerStack.push(new EBCDICRecognizer()); |
| recognizerStack.push(new UCSRecognizer()); |
| recognizerStack.push(new UTF8Recognizer()); |
| } |
| |
| /** |
| * Subclasses override this method to support recognizing their encodings. |
| * |
| * @param readerFactory the factory object to use when constructing the entity reader. |
| * @param entityHandler the entity handler to get entity readers from |
| * @param errorReporter where to report errors |
| * @param sendCharDataAsCharArray true if the reader should use char arrays, not string handles. |
| * @param stringPool the <code>StringPool</code> to put strings in |
| * @param data initial bytes to perform recognition on |
| * @param xmlDecl true if attempting to recognize fron an XMLDecl, false if trying to recognize from a TextDecl. |
| * @param allowJavaEncodingName true if Java's encoding names are allowed, false if they are not. |
| * @return The reader that will be used to process the contents of the data stream. |
| * @exception java.lang.Exception |
| */ |
| public abstract XMLEntityHandler.EntityReader recognize(XMLEntityReaderFactory readerFactory, |
| XMLEntityHandler entityHandler, |
| XMLErrorReporter errorReporter, |
| boolean sendCharDataAsCharArray, |
| StringPool stringPool, |
| ChunkyByteArray data, |
| boolean xmlDecl, |
| boolean allowJavaEncodingName) throws Exception; |
| |
| // |
| // From the standard: |
| // |
| // [23] XMLDecl ::= '<?xml' VersionInfo EncodingDecl? SDDecl? S? '?>' |
| // [24] VersionInfo ::= S 'version' Eq (' VersionNum ' | " VersionNum ") |
| // [80] EncodingDecl ::= S 'encoding' Eq ('"' EncName '"' | "'" EncName "'" ) |
| // [81] EncName ::= [A-Za-z] ([A-Za-z0-9._] | '-')* |
| // [77] TextDecl ::= '<?xml' VersionInfo? EncodingDecl S? '?>' |
| // |
| /** |
| * Support for getting the value of an EncodingDecl using an XMLReader. |
| * |
| * This is the minimal logic from the scanner to recognize an XMLDecl or TextDecl using |
| * the XMLReader interface. |
| * |
| * @param entityReader data source for prescan |
| * @param xmlDecl true if attempting to recognize from an XMLDecl, false if trying to recognize from a TextDecl. |
| * @return <code>StringPool</code> handle to the name of the encoding recognized |
| * @exception java.lang.Exception |
| */ |
| protected int prescanXMLDeclOrTextDecl(XMLEntityHandler.EntityReader entityReader, boolean xmlDecl) throws Exception |
| { |
| if (!entityReader.lookingAtChar('<', true)) { |
| return -1; |
| } |
| if (!entityReader.lookingAtChar('?', true)) { |
| return -1; |
| } |
| if (!entityReader.skippedString(xml_string)) { |
| return -1; |
| } |
| entityReader.skipPastSpaces(); |
| boolean single; |
| char qchar; |
| if (entityReader.skippedString(version_string)) { |
| entityReader.skipPastSpaces(); |
| if (!entityReader.lookingAtChar('=', true)) { |
| return -1; |
| } |
| entityReader.skipPastSpaces(); |
| int versionIndex = entityReader.scanStringLiteral(); |
| if (versionIndex < 0) { |
| return -1; |
| } |
| if (!entityReader.lookingAtSpace(true)) { |
| return -1; |
| } |
| entityReader.skipPastSpaces(); |
| } |
| else if (xmlDecl) { |
| return -1; |
| } |
| if (!entityReader.skippedString(encoding_string)) { |
| return -1; |
| } |
| entityReader.skipPastSpaces(); |
| if (!entityReader.lookingAtChar('=', true)) { |
| return -1; |
| } |
| entityReader.skipPastSpaces(); |
| int encodingIndex = entityReader.scanStringLiteral(); |
| return encodingIndex; |
| } |
| // |
| // [23] XMLDecl ::= '<?xml' VersionInfo EncodingDecl? SDDecl? S? '?>' |
| // [77] TextDecl ::= '<?xml' VersionInfo? EncodingDecl S? '?>' |
| // |
| private static final char[] xml_string = { 'x','m','l' }; |
| // |
| // [24] VersionInfo ::= S 'version' Eq (' VersionNum ' | " VersionNum ") |
| // |
| private static final char[] version_string = { 'v','e','r','s','i','o','n' }; |
| // |
| // [80] EncodingDecl ::= S 'encoding' Eq ('"' EncName '"' | "'" EncName "'" ) |
| // |
| private static final char[] encoding_string = { 'e','n','c','o','d','i','n','g' }; |
| } |
