Struts example source code file (XMLEncodingDetector.java)
The Struts XMLEncodingDetector.java source code/*
* 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.
* ====================================================================
*
* 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.struts2.jasper.xmlparser;
import java.io.EOFException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.Reader;
import java.util.Locale;
import java.util.jar.JarFile;
import org.apache.struts2.jasper.JasperException;
import org.apache.struts2.jasper.JspCompilationContext;
import org.apache.struts2.jasper.compiler.ErrorDispatcher;
import org.apache.struts2.jasper.compiler.JspUtil;
public class XMLEncodingDetector {
private InputStream stream;
private String encoding;
private boolean isEncodingSetInProlog;
private boolean isBomPresent;
private int skip;
private Boolean isBigEndian;
private Reader reader;
// org.apache.xerces.impl.XMLEntityManager fields
public static final int DEFAULT_BUFFER_SIZE = 2048;
public static final int DEFAULT_XMLDECL_BUFFER_SIZE = 64;
private boolean fAllowJavaEncodings;
private SymbolTable fSymbolTable;
private XMLEncodingDetector fCurrentEntity;
private int fBufferSize = DEFAULT_BUFFER_SIZE;
// org.apache.xerces.impl.XMLEntityManager.ScannedEntity fields
private int lineNumber = 1;
private int columnNumber = 1;
private boolean literal;
private char[] ch = new char[DEFAULT_BUFFER_SIZE];
private int position;
private int count;
private boolean mayReadChunks = false;
// org.apache.xerces.impl.XMLScanner fields
private XMLString fString = new XMLString();
private XMLStringBuffer fStringBuffer = new XMLStringBuffer();
private XMLStringBuffer fStringBuffer2 = new XMLStringBuffer();
private final static String fVersionSymbol = "version";
private final static String fEncodingSymbol = "encoding";
private final static String fStandaloneSymbol = "standalone";
// org.apache.xerces.impl.XMLDocumentFragmentScannerImpl fields
private int fMarkupDepth = 0;
private String[] fStrings = new String[3];
private ErrorDispatcher err;
/**
* Constructor
*/
public XMLEncodingDetector() {
fSymbolTable = new SymbolTable();
fCurrentEntity = this;
}
/**
* Autodetects the encoding of the XML document supplied by the given
* input stream.
*
* Encoding autodetection is done according to the XML 1.0 specification,
* Appendix F.1: Detection Without External Encoding Information.
*
* @return Two-element array, where the first element (of type
* java.lang.String) contains the name of the (auto)detected encoding, and
* the second element (of type java.lang.Boolean) specifies whether the
* encoding was specified using the 'encoding' attribute of an XML prolog
* (TRUE) or autodetected (FALSE).
*/
public static Object[] getEncoding(String fname, JarFile jarFile,
JspCompilationContext ctxt,
ErrorDispatcher err)
throws IOException, JasperException
{
InputStream inStream = JspUtil.getInputStream(fname, jarFile, ctxt,
err);
XMLEncodingDetector detector = new XMLEncodingDetector();
Object[] ret = detector.getEncoding(inStream, err);
inStream.close();
return ret;
}
private Object[] getEncoding(InputStream in, ErrorDispatcher err)
throws IOException, JasperException
{
this.stream = in;
this.err=err;
createInitialReader();
scanXMLDecl();
return new Object[] { this.encoding,
Boolean.valueOf(this.isEncodingSetInProlog),
Boolean.valueOf(this.isBomPresent),
Integer.valueOf(this.skip) };
}
// stub method
void endEntity() {
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.startEntity()
private void createInitialReader() throws IOException, JasperException {
// wrap this stream in RewindableInputStream
stream = new RewindableInputStream(stream);
// perform auto-detect of encoding if necessary
if (encoding == null) {
// read first four bytes and determine encoding
final byte[] b4 = new byte[4];
int count = 0;
for (; count<4; count++ ) {
b4[count] = (byte)stream.read();
}
if (count == 4) {
Object [] encodingDesc = getEncodingName(b4, count);
encoding = (String)(encodingDesc[0]);
isBigEndian = (Boolean)(encodingDesc[1]);
if (encodingDesc.length > 3) {
isBomPresent = (Boolean)(encodingDesc[2]);
skip = (Integer)(encodingDesc[3]);
} else {
isBomPresent = true;
skip = (Integer)(encodingDesc[2]);
}
stream.reset();
// Special case UTF-8 files with BOM created by Microsoft
// tools. It's more efficient to consume the BOM than make
// the reader perform extra checks. -Ac
if (count > 2 && encoding.equals("UTF-8")) {
int b0 = b4[0] & 0xFF;
int b1 = b4[1] & 0xFF;
int b2 = b4[2] & 0xFF;
if (b0 == 0xEF && b1 == 0xBB && b2 == 0xBF) {
// ignore first three bytes...
stream.skip(3);
}
}
reader = createReader(stream, encoding, isBigEndian);
} else {
reader = createReader(stream, encoding, isBigEndian);
}
}
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.createReader
/**
* Creates a reader capable of reading the given input stream in
* the specified encoding.
*
* @param inputStream The input stream.
* @param encoding The encoding name that the input stream is
* encoded using. If the user has specified that
* Java encoding names are allowed, then the
* encoding name may be a Java encoding name;
* otherwise, it is an ianaEncoding name.
* @param isBigEndian For encodings (like uCS-4), whose names cannot
* specify a byte order, this tells whether the order
* is bigEndian. null means unknown or not relevant.
*
* @return Returns a reader.
*/
private Reader createReader(InputStream inputStream, String encoding,
Boolean isBigEndian)
throws IOException, JasperException {
// normalize encoding name
if (encoding == null) {
encoding = "UTF-8";
}
// try to use an optimized reader
String ENCODING = encoding.toUpperCase(Locale.ENGLISH);
if (ENCODING.equals("UTF-8")) {
return new UTF8Reader(inputStream, fBufferSize);
}
if (ENCODING.equals("US-ASCII")) {
return new ASCIIReader(inputStream, fBufferSize);
}
if (ENCODING.equals("ISO-10646-UCS-4")) {
if (isBigEndian != null) {
boolean isBE = isBigEndian.booleanValue();
if (isBE) {
return new UCSReader(inputStream, UCSReader.UCS4BE);
} else {
return new UCSReader(inputStream, UCSReader.UCS4LE);
}
} else {
err.jspError("jsp.error.xml.encodingByteOrderUnsupported",
encoding);
}
}
if (ENCODING.equals("ISO-10646-UCS-2")) {
if (isBigEndian != null) { // sould never happen with this encoding...
boolean isBE = isBigEndian.booleanValue();
if (isBE) {
return new UCSReader(inputStream, UCSReader.UCS2BE);
} else {
return new UCSReader(inputStream, UCSReader.UCS2LE);
}
} else {
err.jspError("jsp.error.xml.encodingByteOrderUnsupported",
encoding);
}
}
// check for valid name
boolean validIANA = XMLChar.isValidIANAEncoding(encoding);
boolean validJava = XMLChar.isValidJavaEncoding(encoding);
if (!validIANA || (fAllowJavaEncodings && !validJava)) {
err.jspError("jsp.error.xml.encodingDeclInvalid", encoding);
// NOTE: AndyH suggested that, on failure, we use ISO Latin 1
// because every byte is a valid ISO Latin 1 character.
// It may not translate correctly but if we failed on
// the encoding anyway, then we're expecting the content
// of the document to be bad. This will just prevent an
// invalid UTF-8 sequence to be detected. This is only
// important when continue-after-fatal-error is turned
// on. -Ac
encoding = "ISO-8859-1";
}
// try to use a Java reader
String javaEncoding = EncodingMap.getIANA2JavaMapping(ENCODING);
if (javaEncoding == null) {
if (fAllowJavaEncodings) {
javaEncoding = encoding;
} else {
err.jspError("jsp.error.xml.encodingDeclInvalid", encoding);
// see comment above.
javaEncoding = "ISO8859_1";
}
}
return new InputStreamReader(inputStream, javaEncoding);
} // createReader(InputStream,String, Boolean): Reader
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.getEncodingName
/**
* Returns the IANA encoding name that is auto-detected from
* the bytes specified, with the endian-ness of that encoding where
* appropriate.
*
* @param b4 The first four bytes of the input.
* @param count The number of bytes actually read.
* @return a 2-element array: the first element, an IANA-encoding string,
* the second element a Boolean which is true iff the document is big
* endian, false if it's little-endian, and null if the distinction isn't
* relevant.
*/
private Object[] getEncodingName(byte[] b4, int count) {
if (count < 2) {
return new Object[]{"UTF-8", null, Boolean.FALSE, Integer.valueOf(0)};
}
// UTF-16, with BOM
int b0 = b4[0] & 0xFF;
int b1 = b4[1] & 0xFF;
if (b0 == 0xFE && b1 == 0xFF) {
// UTF-16, big-endian
return new Object [] {"UTF-16BE", Boolean.TRUE, Integer.valueOf(2)};
}
if (b0 == 0xFF && b1 == 0xFE) {
// UTF-16, little-endian
return new Object [] {"UTF-16LE", Boolean.FALSE, Integer.valueOf(2)};
}
// default to UTF-8 if we don't have enough bytes to make a
// good determination of the encoding
if (count < 3) {
return new Object [] {"UTF-8", null, Boolean.FALSE, Integer.valueOf(0)};
}
// UTF-8 with a BOM
int b2 = b4[2] & 0xFF;
if (b0 == 0xEF && b1 == 0xBB && b2 == 0xBF) {
return new Object [] {"UTF-8", null, Integer.valueOf(3)};
}
// default to UTF-8 if we don't have enough bytes to make a
// good determination of the encoding
if (count < 4) {
return new Object [] {"UTF-8", null, Integer.valueOf(0)};
}
// other encodings
int b3 = b4[3] & 0xFF;
if (b0 == 0x00 && b1 == 0x00 && b2 == 0x00 && b3 == 0x3C) {
// UCS-4, big endian (1234)
return new Object [] {"ISO-10646-UCS-4", new Boolean(true), Integer.valueOf(4)};
}
if (b0 == 0x3C && b1 == 0x00 && b2 == 0x00 && b3 == 0x00) {
// UCS-4, little endian (4321)
return new Object [] {"ISO-10646-UCS-4", new Boolean(false), Integer.valueOf(4)};
}
if (b0 == 0x00 && b1 == 0x00 && b2 == 0x3C && b3 == 0x00) {
// UCS-4, unusual octet order (2143)
// REVISIT: What should this be?
return new Object [] {"ISO-10646-UCS-4", null, Integer.valueOf(4)};
}
if (b0 == 0x00 && b1 == 0x3C && b2 == 0x00 && b3 == 0x00) {
// UCS-4, unusual octect order (3412)
// REVISIT: What should this be?
return new Object [] {"ISO-10646-UCS-4", null, Integer.valueOf(4)};
}
if (b0 == 0x00 && b1 == 0x3C && b2 == 0x00 && b3 == 0x3F) {
// UTF-16, big-endian, no BOM
// (or could turn out to be UCS-2...
// REVISIT: What should this be?
return new Object [] {"UTF-16BE", new Boolean(true), Integer.valueOf(4)};
}
if (b0 == 0x3C && b1 == 0x00 && b2 == 0x3F && b3 == 0x00) {
// UTF-16, little-endian, no BOM
// (or could turn out to be UCS-2...
return new Object [] {"UTF-16LE", new Boolean(false), Integer.valueOf(4)};
}
if (b0 == 0x4C && b1 == 0x6F && b2 == 0xA7 && b3 == 0x94) {
// EBCDIC
// a la xerces1, return CP037 instead of EBCDIC here
return new Object [] {"CP037", null, Integer.valueOf(4)};
}
// default encoding
return new Object [] {"UTF-8", null, Boolean.FALSE, Integer.valueOf(0)};
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.isExternal
/** Returns true if the current entity being scanned is external. */
public boolean isExternal() {
return true;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.peekChar
/**
* Returns the next character on the input.
* <p>
* <strong>Note: The character is not consumed.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public int peekChar() throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// peek at character
int c = fCurrentEntity.ch[fCurrentEntity.position];
// return peeked character
if (fCurrentEntity.isExternal()) {
return c != '\r' ? c : '\n';
}
else {
return c;
}
} // peekChar():int
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.scanChar
/**
* Returns the next character on the input.
* <p>
* <strong>Note: The character is consumed.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public int scanChar() throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// scan character
int c = fCurrentEntity.ch[fCurrentEntity.position++];
boolean external = false;
if (c == '\n' ||
(c == '\r' && (external = fCurrentEntity.isExternal()))) {
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count) {
fCurrentEntity.ch[0] = (char)c;
load(1, false);
}
if (c == '\r' && external) {
if (fCurrentEntity.ch[fCurrentEntity.position++] != '\n') {
fCurrentEntity.position--;
}
c = '\n';
}
}
// return character that was scanned
fCurrentEntity.columnNumber++;
return c;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.scanName
/**
* Returns a string matching the Name production appearing immediately
* on the input as a symbol, or null if no Name string is present.
* <p>
* <strong>Note: The Name characters are consumed.
* <p>
* <strong>Note: The string returned must be a symbol. The
* SymbolTable can be used for this purpose.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*
* @see SymbolTable
* @see XMLChar#isName
* @see XMLChar#isNameStart
*/
public String scanName() throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// scan name
int offset = fCurrentEntity.position;
if (XMLChar.isNameStart(fCurrentEntity.ch[offset])) {
if (++fCurrentEntity.position == fCurrentEntity.count) {
fCurrentEntity.ch[0] = fCurrentEntity.ch[offset];
offset = 0;
if (load(1, false)) {
fCurrentEntity.columnNumber++;
String symbol = fSymbolTable.addSymbol(fCurrentEntity.ch,
0, 1);
return symbol;
}
}
while (XMLChar.isName(fCurrentEntity.ch[fCurrentEntity.position])) {
if (++fCurrentEntity.position == fCurrentEntity.count) {
int length = fCurrentEntity.position - offset;
if (length == fBufferSize) {
// bad luck we have to resize our buffer
char[] tmp = new char[fBufferSize * 2];
System.arraycopy(fCurrentEntity.ch, offset,
tmp, 0, length);
fCurrentEntity.ch = tmp;
fBufferSize *= 2;
} else {
System.arraycopy(fCurrentEntity.ch, offset,
fCurrentEntity.ch, 0, length);
}
offset = 0;
if (load(length, false)) {
break;
}
}
}
}
int length = fCurrentEntity.position - offset;
fCurrentEntity.columnNumber += length;
// return name
String symbol = null;
if (length > 0) {
symbol = fSymbolTable.addSymbol(fCurrentEntity.ch, offset, length);
}
return symbol;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.scanLiteral
/**
* Scans a range of attribute value data, setting the fields of the
* XMLString structure, appropriately.
* <p>
* <strong>Note: The characters are consumed.
* <p>
* <strong>Note: This method does not guarantee to return
* the longest run of attribute value data. This method may return
* before the quote character due to reaching the end of the input
* buffer or any other reason.
* <p>
* <strong>Note: The fields contained in the XMLString
* structure are not guaranteed to remain valid upon subsequent calls
* to the entity scanner. Therefore, the caller is responsible for
* immediately using the returned character data or making a copy of
* the character data.
*
* @param quote The quote character that signifies the end of the
* attribute value data.
* @param content The content structure to fill.
*
* @return Returns the next character on the input, if known. This
* value may be -1 but this does <em>note designate
* end of file.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public int scanLiteral(int quote, XMLString content)
throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
} else if (fCurrentEntity.position == fCurrentEntity.count - 1) {
fCurrentEntity.ch[0] = fCurrentEntity.ch[fCurrentEntity.count - 1];
load(1, false);
fCurrentEntity.position = 0;
}
// normalize newlines
int offset = fCurrentEntity.position;
int c = fCurrentEntity.ch[offset];
int newlines = 0;
boolean external = fCurrentEntity.isExternal();
if (c == '\n' || (c == '\r' && external)) {
do {
c = fCurrentEntity.ch[fCurrentEntity.position++];
if (c == '\r' && external) {
newlines++;
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count) {
offset = 0;
fCurrentEntity.position = newlines;
if (load(newlines, false)) {
break;
}
}
if (fCurrentEntity.ch[fCurrentEntity.position] == '\n') {
fCurrentEntity.position++;
offset++;
}
/*** NEWLINE NORMALIZATION ***/
else {
newlines++;
}
/***/
}
else if (c == '\n') {
newlines++;
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count) {
offset = 0;
fCurrentEntity.position = newlines;
if (load(newlines, false)) {
break;
}
}
/*** NEWLINE NORMALIZATION ***
if (fCurrentEntity.ch[fCurrentEntity.position] == '\r'
&& external) {
fCurrentEntity.position++;
offset++;
}
/***/
}
else {
fCurrentEntity.position--;
break;
}
} while (fCurrentEntity.position < fCurrentEntity.count - 1);
for (int i = offset; i < fCurrentEntity.position; i++) {
fCurrentEntity.ch[i] = '\n';
}
int length = fCurrentEntity.position - offset;
if (fCurrentEntity.position == fCurrentEntity.count - 1) {
content.setValues(fCurrentEntity.ch, offset, length);
return -1;
}
}
// scan literal value
while (fCurrentEntity.position < fCurrentEntity.count) {
c = fCurrentEntity.ch[fCurrentEntity.position++];
if ((c == quote &&
(!fCurrentEntity.literal || external))
|| c == '%' || !XMLChar.isContent(c)) {
fCurrentEntity.position--;
break;
}
}
int length = fCurrentEntity.position - offset;
fCurrentEntity.columnNumber += length - newlines;
content.setValues(fCurrentEntity.ch, offset, length);
// return next character
if (fCurrentEntity.position != fCurrentEntity.count) {
c = fCurrentEntity.ch[fCurrentEntity.position];
// NOTE: We don't want to accidentally signal the
// end of the literal if we're expanding an
// entity appearing in the literal. -Ac
if (c == quote && fCurrentEntity.literal) {
c = -1;
}
}
else {
c = -1;
}
return c;
}
/**
* Scans a range of character data up to the specified delimiter,
* setting the fields of the XMLString structure, appropriately.
* <p>
* <strong>Note: The characters are consumed.
* <p>
* <strong>Note: This assumes that the internal buffer is
* at least the same size, or bigger, than the length of the delimiter
* and that the delimiter contains at least one character.
* <p>
* <strong>Note: This method does not guarantee to return
* the longest run of character data. This method may return before
* the delimiter due to reaching the end of the input buffer or any
* other reason.
* <p>
* <strong>Note: The fields contained in the XMLString
* structure are not guaranteed to remain valid upon subsequent calls
* to the entity scanner. Therefore, the caller is responsible for
* immediately using the returned character data or making a copy of
* the character data.
*
* @param delimiter The string that signifies the end of the character
* data to be scanned.
* @param buffer The data structure to fill.
*
* @return Returns true if there is more data to scan, false otherwise.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public boolean scanData(String delimiter, XMLStringBuffer buffer)
throws IOException {
boolean done = false;
int delimLen = delimiter.length();
char charAt0 = delimiter.charAt(0);
boolean external = fCurrentEntity.isExternal();
do {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
else if (fCurrentEntity.position >= fCurrentEntity.count - delimLen) {
System.arraycopy(fCurrentEntity.ch, fCurrentEntity.position,
fCurrentEntity.ch, 0, fCurrentEntity.count - fCurrentEntity.position);
load(fCurrentEntity.count - fCurrentEntity.position, false);
fCurrentEntity.position = 0;
}
if (fCurrentEntity.position >= fCurrentEntity.count - delimLen) {
// something must be wrong with the input: e.g., file ends an
// unterminated comment
int length = fCurrentEntity.count - fCurrentEntity.position;
buffer.append (fCurrentEntity.ch, fCurrentEntity.position,
length);
fCurrentEntity.columnNumber += fCurrentEntity.count;
fCurrentEntity.position = fCurrentEntity.count;
load(0,true);
return false;
}
// normalize newlines
int offset = fCurrentEntity.position;
int c = fCurrentEntity.ch[offset];
int newlines = 0;
if (c == '\n' || (c == '\r' && external)) {
do {
c = fCurrentEntity.ch[fCurrentEntity.position++];
if (c == '\r' && external) {
newlines++;
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count) {
offset = 0;
fCurrentEntity.position = newlines;
if (load(newlines, false)) {
break;
}
}
if (fCurrentEntity.ch[fCurrentEntity.position] == '\n') {
fCurrentEntity.position++;
offset++;
}
/*** NEWLINE NORMALIZATION ***/
else {
newlines++;
}
}
else if (c == '\n') {
newlines++;
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count) {
offset = 0;
fCurrentEntity.position = newlines;
fCurrentEntity.count = newlines;
if (load(newlines, false)) {
break;
}
}
}
else {
fCurrentEntity.position--;
break;
}
} while (fCurrentEntity.position < fCurrentEntity.count - 1);
for (int i = offset; i < fCurrentEntity.position; i++) {
fCurrentEntity.ch[i] = '\n';
}
int length = fCurrentEntity.position - offset;
if (fCurrentEntity.position == fCurrentEntity.count - 1) {
buffer.append(fCurrentEntity.ch, offset, length);
return true;
}
}
// iterate over buffer looking for delimiter
OUTER: while (fCurrentEntity.position < fCurrentEntity.count) {
c = fCurrentEntity.ch[fCurrentEntity.position++];
if (c == charAt0) {
// looks like we just hit the delimiter
int delimOffset = fCurrentEntity.position - 1;
for (int i = 1; i < delimLen; i++) {
if (fCurrentEntity.position == fCurrentEntity.count) {
fCurrentEntity.position -= i;
break OUTER;
}
c = fCurrentEntity.ch[fCurrentEntity.position++];
if (delimiter.charAt(i) != c) {
fCurrentEntity.position--;
break;
}
}
if (fCurrentEntity.position == delimOffset + delimLen) {
done = true;
break;
}
}
else if (c == '\n' || (external && c == '\r')) {
fCurrentEntity.position--;
break;
}
else if (XMLChar.isInvalid(c)) {
fCurrentEntity.position--;
int length = fCurrentEntity.position - offset;
fCurrentEntity.columnNumber += length - newlines;
buffer.append(fCurrentEntity.ch, offset, length);
return true;
}
}
int length = fCurrentEntity.position - offset;
fCurrentEntity.columnNumber += length - newlines;
if (done) {
length -= delimLen;
}
buffer.append (fCurrentEntity.ch, offset, length);
// return true if string was skipped
} while (!done);
return !done;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.skipChar
/**
* Skips a character appearing immediately on the input.
* <p>
* <strong>Note: The character is consumed only if it matches
* the specified character.
*
* @param c The character to skip.
*
* @return Returns true if the character was skipped.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public boolean skipChar(int c) throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// skip character
int cc = fCurrentEntity.ch[fCurrentEntity.position];
if (cc == c) {
fCurrentEntity.position++;
if (c == '\n') {
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
}
else {
fCurrentEntity.columnNumber++;
}
return true;
} else if (c == '\n' && cc == '\r' && fCurrentEntity.isExternal()) {
// handle newlines
if (fCurrentEntity.position == fCurrentEntity.count) {
fCurrentEntity.ch[0] = (char)cc;
load(1, false);
}
fCurrentEntity.position++;
if (fCurrentEntity.ch[fCurrentEntity.position] == '\n') {
fCurrentEntity.position++;
}
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
return true;
}
// character was not skipped
return false;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.skipSpaces
/**
* Skips space characters appearing immediately on the input.
* <p>
* <strong>Note: The characters are consumed only if they are
* space characters.
*
* @return Returns true if at least one space character was skipped.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*
* @see XMLChar#isSpace
*/
public boolean skipSpaces() throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// skip spaces
int c = fCurrentEntity.ch[fCurrentEntity.position];
if (XMLChar.isSpace(c)) {
boolean external = fCurrentEntity.isExternal();
do {
boolean entityChanged = false;
// handle newlines
if (c == '\n' || (external && c == '\r')) {
fCurrentEntity.lineNumber++;
fCurrentEntity.columnNumber = 1;
if (fCurrentEntity.position == fCurrentEntity.count - 1) {
fCurrentEntity.ch[0] = (char)c;
entityChanged = load(1, true);
if (!entityChanged)
// the load change the position to be 1,
// need to restore it when entity not changed
fCurrentEntity.position = 0;
}
if (c == '\r' && external) {
// REVISIT: Does this need to be updated to fix the
// #x0D ^#x0A newline normalization problem? -Ac
if (fCurrentEntity.ch[++fCurrentEntity.position] != '\n') {
fCurrentEntity.position--;
}
}
/*** NEWLINE NORMALIZATION ***
else {
if (fCurrentEntity.ch[fCurrentEntity.position + 1] == '\r'
&& external) {
fCurrentEntity.position++;
}
}
/***/
}
else {
fCurrentEntity.columnNumber++;
}
// load more characters, if needed
if (!entityChanged)
fCurrentEntity.position++;
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
} while (XMLChar.isSpace(c = fCurrentEntity.ch[fCurrentEntity.position]));
return true;
}
// no spaces were found
return false;
}
/**
* Skips the specified string appearing immediately on the input.
* <p>
* <strong>Note: The characters are consumed only if they are
* space characters.
*
* @param s The string to skip.
*
* @return Returns true if the string was skipped.
*
* @throws IOException Thrown if i/o error occurs.
* @throws EOFException Thrown on end of file.
*/
public boolean skipString(String s) throws IOException {
// load more characters, if needed
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, true);
}
// skip string
final int length = s.length();
for (int i = 0; i < length; i++) {
char c = fCurrentEntity.ch[fCurrentEntity.position++];
if (c != s.charAt(i)) {
fCurrentEntity.position -= i + 1;
return false;
}
if (i < length - 1 && fCurrentEntity.position == fCurrentEntity.count) {
System.arraycopy(fCurrentEntity.ch, fCurrentEntity.count - i - 1, fCurrentEntity.ch, 0, i + 1);
// REVISIT: Can a string to be skipped cross an
// entity boundary? -Ac
if (load(i + 1, false)) {
fCurrentEntity.position -= i + 1;
return false;
}
}
}
fCurrentEntity.columnNumber += length;
return true;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.EntityScanner.load
/**
* Loads a chunk of text.
*
* @param offset The offset into the character buffer to
* read the next batch of characters.
* @param changeEntity True if the load should change entities
* at the end of the entity, otherwise leave
* the current entity in place and the entity
* boundary will be signaled by the return
* value.
*
* @returns Returns true if the entity changed as a result of this
* load operation.
*/
final boolean load(int offset, boolean changeEntity)
throws IOException {
// read characters
int length = fCurrentEntity.mayReadChunks?
(fCurrentEntity.ch.length - offset):
(DEFAULT_XMLDECL_BUFFER_SIZE);
int count = fCurrentEntity.reader.read(fCurrentEntity.ch, offset,
length);
// reset count and position
boolean entityChanged = false;
if (count != -1) {
if (count != 0) {
fCurrentEntity.count = count + offset;
fCurrentEntity.position = offset;
}
}
// end of this entity
else {
fCurrentEntity.count = offset;
fCurrentEntity.position = offset;
entityChanged = true;
if (changeEntity) {
endEntity();
if (fCurrentEntity == null) {
throw new EOFException();
}
// handle the trailing edges
if (fCurrentEntity.position == fCurrentEntity.count) {
load(0, false);
}
}
}
return entityChanged;
}
// Adapted from:
// org.apache.xerces.impl.XMLEntityManager.RewindableInputStream
/**
* This class wraps the byte inputstreams we're presented with.
* We need it because java.io.InputStreams don't provide
* functionality to reread processed bytes, and they have a habit
* of reading more than one character when you call their read()
* methods. This means that, once we discover the true (declared)
* encoding of a document, we can neither backtrack to read the
* whole doc again nor start reading where we are with a new
* reader.
*
* This class allows rewinding an inputStream by allowing a mark
* to be set, and the stream reset to that position. <strong>The
* class assumes that it needs to read one character per
* invocation when it's read() method is inovked, but uses the
* underlying InputStream's read(char[], offset length) method--it
* won't buffer data read this way!</strong>
*
* @author Neil Graham, IBM
* @author Glenn Marcy, IBM
*/
private final class RewindableInputStream extends InputStream {
private InputStream fInputStream;
private byte[] fData;
private int fStartOffset;
private int fEndOffset;
private int fOffset;
private int fLength;
private int fMark;
public RewindableInputStream(InputStream is) {
fData = new byte[DEFAULT_XMLDECL_BUFFER_SIZE];
fInputStream = is;
fStartOffset = 0;
fEndOffset = -1;
fOffset = 0;
fLength = 0;
fMark = 0;
}
public void setStartOffset(int offset) {
fStartOffset = offset;
}
public void rewind() {
fOffset = fStartOffset;
}
public int read() throws IOException {
int b = 0;
if (fOffset < fLength) {
return fData[fOffset++] & 0xff;
}
if (fOffset == fEndOffset) {
return -1;
}
if (fOffset == fData.length) {
byte[] newData = new byte[fOffset << 1];
System.arraycopy(fData, 0, newData, 0, fOffset);
fData = newData;
}
b = fInputStream.read();
if (b == -1) {
fEndOffset = fOffset;
return -1;
}
fData[fLength++] = (byte)b;
fOffset++;
return b & 0xff;
}
public int read(byte[] b, int off, int len) throws IOException {
int bytesLeft = fLength - fOffset;
if (bytesLeft == 0) {
if (fOffset == fEndOffset) {
return -1;
}
// better get some more for the voracious reader...
if (fCurrentEntity.mayReadChunks) {
return fInputStream.read(b, off, len);
}
int returnedVal = read();
if (returnedVal == -1) {
fEndOffset = fOffset;
return -1;
}
b[off] = (byte)returnedVal;
return 1;
}
if (len < bytesLeft) {
if (len <= 0) {
return 0;
}
}
else {
len = bytesLeft;
}
if (b != null) {
System.arraycopy(fData, fOffset, b, off, len);
}
fOffset += len;
return len;
}
public long skip(long n)
throws IOException
{
int bytesLeft;
if (n <= 0) {
return 0;
}
bytesLeft = fLength - fOffset;
if (bytesLeft == 0) {
if (fOffset == fEndOffset) {
return 0;
}
return fInputStream.skip(n);
}
if (n <= bytesLeft) {
fOffset += n;
return n;
}
fOffset += bytesLeft;
if (fOffset == fEndOffset) {
return bytesLeft;
}
n -= bytesLeft;
/*
* In a manner of speaking, when this class isn't permitting more
* than one byte at a time to be read, it is "blocking". The
* available() method should indicate how much can be read without
* blocking, so while we're in this mode, it should only indicate
* that bytes in its buffer are available; otherwise, the result of
* available() on the underlying InputStream is appropriate.
*/
return fInputStream.skip(n) + bytesLeft;
}
public int available() throws IOException {
int bytesLeft = fLength - fOffset;
if (bytesLeft == 0) {
if (fOffset == fEndOffset) {
return -1;
}
return fCurrentEntity.mayReadChunks ? fInputStream.available()
: 0;
}
return bytesLeft;
}
public void mark(int howMuch) {
fMark = fOffset;
}
public void reset() {
fOffset = fMark;
}
public boolean markSupported() {
return true;
}
public void close() throws IOException {
if (fInputStream != null) {
fInputStream.close();
fInputStream = null;
}
}
} // end of RewindableInputStream class
// Adapted from:
// org.apache.xerces.impl.XMLDocumentScannerImpl.dispatch
private void scanXMLDecl() throws IOException, JasperException {
if (skipString("<?xml")) {
fMarkupDepth++;
// NOTE: special case where document starts with a PI
// whose name starts with "xml" (e.g. "xmlfoo")
if (XMLChar.isName(peekChar())) {
fStringBuffer.clear();
fStringBuffer.append("xml");
while (XMLChar.isName(peekChar())) {
fStringBuffer.append((char)scanChar());
}
String target = fSymbolTable.addSymbol(fStringBuffer.ch,
fStringBuffer.offset,
fStringBuffer.length);
scanPIData(target, fString);
}
// standard XML declaration
else {
scanXMLDeclOrTextDecl(false);
}
}
}
// Adapted from:
// org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanXMLDeclOrTextDecl
/**
* Scans an XML or text declaration.
* <p>
* <pre>
* [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._] | '-')*
* [32] SDDecl ::= S 'standalone' Eq (("'" ('yes' | 'no') "'")
* | ('"' ('yes' | 'no') '"'))
*
* [77] TextDecl ::= '<?xml' VersionInfo? EncodingDecl S? '?>'
* </pre>
*
* @param scanningTextDecl True if a text declaration is to
* be scanned instead of an XML
* declaration.
*/
private void scanXMLDeclOrTextDecl(boolean scanningTextDecl)
throws IOException, JasperException {
// scan decl
scanXMLDeclOrTextDecl(scanningTextDecl, fStrings);
fMarkupDepth--;
// pseudo-attribute values
String encodingPseudoAttr = fStrings[1];
// set encoding on reader
if (encodingPseudoAttr != null) {
isEncodingSetInProlog = true;
encoding = encodingPseudoAttr;
}
}
// Adapted from:
// org.apache.xerces.impl.XMLScanner.scanXMLDeclOrTextDecl
/**
* Scans an XML or text declaration.
* <p>
* <pre>
* [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._] | '-')*
* [32] SDDecl ::= S 'standalone' Eq (("'" ('yes' | 'no') "'")
* | ('"' ('yes' | 'no') '"'))
*
* [77] TextDecl ::= '<?xml' VersionInfo? EncodingDecl S? '?>'
* </pre>
*
* @param scanningTextDecl True if a text declaration is to
* be scanned instead of an XML
* declaration.
* @param pseudoAttributeValues An array of size 3 to return the version,
* encoding and standalone pseudo attribute values
* (in that order).
*
* <strong>Note: This method uses fString, anything in it
* at the time of calling is lost.
*/
private void scanXMLDeclOrTextDecl(boolean scanningTextDecl,
String[] pseudoAttributeValues)
throws IOException, JasperException {
// pseudo-attribute values
String version = null;
String encoding = null;
String standalone = null;
// scan pseudo-attributes
final int STATE_VERSION = 0;
final int STATE_ENCODING = 1;
final int STATE_STANDALONE = 2;
final int STATE_DONE = 3;
int state = STATE_VERSION;
boolean dataFoundForTarget = false;
boolean sawSpace = skipSpaces();
while (peekChar() != '?') {
dataFoundForTarget = true;
String name = scanPseudoAttribute(scanningTextDecl, fString);
switch (state) {
case STATE_VERSION: {
if (name == fVersionSymbol) {
if (!sawSpace) {
reportFatalError(scanningTextDecl
? "jsp.error.xml.spaceRequiredBeforeVersionInTextDecl"
: "jsp.error.xml.spaceRequiredBeforeVersionInXMLDecl",
null);
}
version = fString.toString();
state = STATE_ENCODING;
if (!version.equals("1.0")) {
// REVISIT: XML REC says we should throw an error
// in such cases.
// some may object the throwing of fatalError.
err.jspError("jsp.error.xml.versionNotSupported",
version);
}
} else if (name == fEncodingSymbol) {
if (!scanningTextDecl) {
err.jspError("jsp.error.xml.versionInfoRequired");
}
if (!sawSpace) {
reportFatalError(scanningTextDecl
? "jsp.error.xml.spaceRequiredBeforeEncodingInTextDecl"
: "jsp.error.xml.spaceRequiredBeforeEncodingInXMLDecl",
null);
}
encoding = fString.toString();
state = scanningTextDecl ? STATE_DONE : STATE_STANDALONE;
} else {
if (scanningTextDecl) {
err.jspError("jsp.error.xml.encodingDeclRequired");
}
else {
err.jspError("jsp.error.xml.versionInfoRequired");
}
}
break;
}
case STATE_ENCODING: {
if (name == fEncodingSymbol) {
if (!sawSpace) {
reportFatalError(scanningTextDecl
? "jsp.error.xml.spaceRequiredBeforeEncodingInTextDecl"
: "jsp.error.xml.spaceRequiredBeforeEncodingInXMLDecl",
null);
}
encoding = fString.toString();
state = scanningTextDecl ? STATE_DONE : STATE_STANDALONE;
// TODO: check encoding name; set encoding on
// entity scanner
} else if (!scanningTextDecl && name == fStandaloneSymbol) {
if (!sawSpace) {
err.jspError("jsp.error.xml.spaceRequiredBeforeStandalone");
}
standalone = fString.toString();
state = STATE_DONE;
if (!standalone.equals("yes") && !standalone.equals("no")) {
err.jspError("jsp.error.xml.sdDeclInvalid");
}
} else {
err.jspError("jsp.error.xml.encodingDeclRequired");
}
break;
}
case STATE_STANDALONE: {
if (name == fStandaloneSymbol) {
if (!sawSpace) {
err.jspError("jsp.error.xml.spaceRequiredBeforeStandalone");
}
standalone = fString.toString();
state = STATE_DONE;
if (!standalone.equals("yes") && !standalone.equals("no")) {
err.jspError("jsp.error.xml.sdDeclInvalid");
}
} else {
err.jspError("jsp.error.xml.encodingDeclRequired");
}
break;
}
default: {
err.jspError("jsp.error.xml.noMorePseudoAttributes");
}
}
sawSpace = skipSpaces();
}
// REVISIT: should we remove this error reporting?
if (scanningTextDecl && state != STATE_DONE) {
err.jspError("jsp.error.xml.morePseudoAttributes");
}
// If there is no data in the xml or text decl then we fail to report
// error for version or encoding info above.
if (scanningTextDecl) {
if (!dataFoundForTarget && encoding == null) {
err.jspError("jsp.error.xml.encodingDeclRequired");
}
} else {
if (!dataFoundForTarget && version == null) {
err.jspError("jsp.error.xml.versionInfoRequired");
}
}
// end
if (!skipChar('?')) {
err.jspError("jsp.error.xml.xmlDeclUnterminated");
}
if (!skipChar('>')) {
err.jspError("jsp.error.xml.xmlDeclUnterminated");
}
// fill in return array
pseudoAttributeValues[0] = version;
pseudoAttributeValues[1] = encoding;
pseudoAttributeValues[2] = standalone;
}
// Adapted from:
// org.apache.xerces.impl.XMLScanner.scanPseudoAttribute
/**
* Scans a pseudo attribute.
*
* @param scanningTextDecl True if scanning this pseudo-attribute for a
* TextDecl; false if scanning XMLDecl. This
* flag is needed to report the correct type of
* error.
* @param value The string to fill in with the attribute
* value.
*
* @return The name of the attribute
*
* <strong>Note: This method uses fStringBuffer2, anything in it
* at the time of calling is lost.
*/
public String scanPseudoAttribute(boolean scanningTextDecl,
XMLString value)
throws IOException, JasperException {
String name = scanName();
if (name == null) {
err.jspError("jsp.error.xml.pseudoAttrNameExpected");
}
skipSpaces();
if (!skipChar('=')) {
reportFatalError(scanningTextDecl ?
"jsp.error.xml.eqRequiredInTextDecl"
: "jsp.error.xml.eqRequiredInXMLDecl",
name);
}
skipSpaces();
int quote = peekChar();
if (quote != '\'' && quote != '"') {
reportFatalError(scanningTextDecl ?
"jsp.error.xml.quoteRequiredInTextDecl"
: "jsp.error.xml.quoteRequiredInXMLDecl" ,
name);
}
scanChar();
int c = scanLiteral(quote, value);
if (c != quote) {
fStringBuffer2.clear();
do {
fStringBuffer2.append(value);
if (c != -1) {
if (c == '&' || c == '%' || c == '<' || c == ']') {
fStringBuffer2.append((char)scanChar());
}
else if (XMLChar.isHighSurrogate(c)) {
scanSurrogates(fStringBuffer2);
}
else if (XMLChar.isInvalid(c)) {
String key = scanningTextDecl
? "jsp.error.xml.invalidCharInTextDecl"
: "jsp.error.xml.invalidCharInXMLDecl";
reportFatalError(key, Integer.toString(c, 16));
scanChar();
}
}
c = scanLiteral(quote, value);
} while (c != quote);
fStringBuffer2.append(value);
value.setValues(fStringBuffer2);
}
if (!skipChar(quote)) {
reportFatalError(scanningTextDecl ?
"jsp.error.xml.closeQuoteMissingInTextDecl"
: "jsp.error.xml.closeQuoteMissingInXMLDecl",
name);
}
// return
return name;
}
// Adapted from:
// org.apache.xerces.impl.XMLScanner.scanPIData
/**
* Scans a processing data. This is needed to handle the situation
* where a document starts with a processing instruction whose
* target name <em>starts with "xml". (e.g. xmlfoo)
*
* <strong>Note: This method uses fStringBuffer, anything in it
* at the time of calling is lost.
*
* @param target The PI target
* @param data The string to fill in with the data
*/
private void scanPIData(String target, XMLString data)
throws IOException, JasperException {
// check target
if (target.length() == 3) {
char c0 = Character.toLowerCase(target.charAt(0));
char c1 = Character.toLowerCase(target.charAt(1));
char c2 = Character.toLowerCase(target.charAt(2));
if (c0 == 'x' && c1 == 'm' && c2 == 'l') {
err.jspError("jsp.error.xml.reservedPITarget");
}
}
// spaces
if (!skipSpaces()) {
if (skipString("?>")) {
// we found the end, there is no data
data.clear();
return;
}
else {
// if there is data there should be some space
err.jspError("jsp.error.xml.spaceRequiredInPI");
}
}
fStringBuffer.clear();
// data
if (scanData("?>", fStringBuffer)) {
do {
int c = peekChar();
if (c != -1) {
if (XMLChar.isHighSurrogate(c)) {
scanSurrogates(fStringBuffer);
} else if (XMLChar.isInvalid(c)) {
err.jspError("jsp.error.xml.invalidCharInPI",
Integer.toHexString(c));
scanChar();
}
}
} while (scanData("?>", fStringBuffer));
}
data.setValues(fStringBuffer);
}
// Adapted from:
// org.apache.xerces.impl.XMLScanner.scanSurrogates
/**
* Scans surrogates and append them to the specified buffer.
* <p>
* <strong>Note: This assumes the current char has already been
* identified as a high surrogate.
*
* @param buf The StringBuffer to append the read surrogates to.
* @returns True if it succeeded.
*/
private boolean scanSurrogates(XMLStringBuffer buf)
throws IOException, JasperException {
int high = scanChar();
int low = peekChar();
if (!XMLChar.isLowSurrogate(low)) {
err.jspError("jsp.error.xml.invalidCharInContent",
Integer.toString(high, 16));
return false;
}
scanChar();
// convert surrogates to supplemental character
int c = XMLChar.supplemental((char)high, (char)low);
// supplemental character must be a valid XML character
if (!XMLChar.isValid(c)) {
err.jspError("jsp.error.xml.invalidCharInContent",
Integer.toString(c, 16));
return false;
}
// fill in the buffer
buf.append((char)high);
buf.append((char)low);
return true;
}
// Adapted from:
// org.apache.xerces.impl.XMLScanner.reportFatalError
/**
* Convenience function used in all XML scanners.
*/
private void reportFatalError(String msgId, String arg)
throws JasperException {
err.jspError(msgId, arg);
}
}
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