src.java.com.ctc.wstx.sw.BufferingXmlWriter Maven / Gradle / Ivy
/* Woodstox XML processor
*
* Copyright (c) 2004- Tatu Saloranta, [email protected]
*
* Licensed under the License specified in file LICENSE, included with
* the source code.
* You may not use this file except in compliance with the License.
*
* 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.ctc.wstx.sw;
import java.io.*;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import org.codehaus.stax2.XMLStreamReader2;
import com.ctc.wstx.api.WriterConfig;
import com.ctc.wstx.io.CharsetNames;
/**
* Concrete implementation of {@link XmlWriter} that will dispatch writes
* to another writer (of type {@link java.io.Writer}, and will NOT handle
* encoding. It will, however, do basic buffering such that the underlying
* Writer need (and thus, should) not do buffering.
*
* One design goal for this class is to avoid unnecessary buffering: since
* there will be another Writer doing the actual encoding, amount of
* buffering needed should still be limited. To this end, a threshold is
* used to define what's the threshold of writes that we do want to
* coalesce, ie. buffer. Writes bigger than this should in general proceed
* without buffering.
*/
public final class BufferingXmlWriter
extends XmlWriter
implements XMLStreamConstants
{
/**
* Let's use a typical default to have a compromise between large
* enough chunks to output, and minimizing memory overhead.
* Compared to encoding writers, buffer size can be bit smaller
* since there's one more level of processing (at encoding), which
* may use bigger buffering.
*/
final static int DEFAULT_BUFFER_SIZE = 1000;
/**
* Choosing threshold for 'small size' is a compromise between
* excessive buffering (high small size), and too many fragmented
* calls to the underlying writer (low small size). Let's just
* use about 1/4 of the full buffer size.
*/
final static int DEFAULT_SMALL_SIZE = 256;
/**
* Highest valued character that may need to be encoded (minus charset
* encoding requirements) when writing attribute values.
*/
protected final static int HIGHEST_ENCODABLE_ATTR_CHAR = (int)'<';
/**
* Highest valued character that may need to be encoded (minus charset
* encoding requirements) when writing attribute values.
*/
protected final static int HIGHEST_ENCODABLE_TEXT_CHAR = (int)'>';
/*
////////////////////////////////////////////////
// Output state, buffering
////////////////////////////////////////////////
*/
/**
* Actual Writer to use for outputting buffered data as appropriate.
* During active usage, remains as the writer initially set; set to
* null when this writer is closed.
*/
protected Writer mOut;
protected char[] mOutputBuffer;
/**
* This is the threshold used to check what is considered a "small"
* write; small writes will be buffered until resulting size will
* be above the threshold.
*/
protected final int mSmallWriteSize;
protected int mOutputPtr;
protected int mOutputBufLen;
/**
* Actual physical stream that the writer is using, if known.
*/
protected OutputStream mUnderlyingStream;
/*
////////////////////////////////////////////////
// Encoding/escaping configuration
////////////////////////////////////////////////
*/
/**
* First Unicode character (one with lowest value) after (and including)
* which character entities have to be used. For
*/
private final int mEncHighChar;
/**
* Character that is considered to be the enclosing quote character;
* for XML either single or double quote.
*/
final char mEncQuoteChar;
/**
* Entity String to use for escaping the quote character.
*/
final String mEncQuoteEntity;
/*
////////////////////////////////////////////////
// Life-cycle
////////////////////////////////////////////////
*/
/**
* @param outs Underlying OutputStream that the writer
* (out) is using, if known. Needed to support
* (optional) access to the underlying stream
*/
public BufferingXmlWriter(Writer out, WriterConfig cfg, String enc,
boolean autoclose,
OutputStream outs)
throws IOException
{
super(cfg, enc, autoclose);
mOut = out;
mOutputBuffer = cfg.allocFullCBuffer(DEFAULT_BUFFER_SIZE);
mOutputBufLen = mOutputBuffer.length;
mSmallWriteSize = DEFAULT_SMALL_SIZE;
mOutputPtr = 0;
mUnderlyingStream = outs;
// Let's use double-quotes, as usual; alternative is apostrophe
mEncQuoteChar = '"';
mEncQuoteEntity = """;
/* Note: let's actually exclude couple of illegal chars for
* unicode-based encoders. But we do not have to worry about
* surrogates quite here, fortunately.
*/
int bitsize = guessEncodingBitSize(enc);
mEncHighChar = ((bitsize < 16) ? (1 << bitsize) : 0xFFFE);
}
protected int getOutputPtr() {
return mOutputPtr;
}
/*
////////////////////////////////////////////////
// Raw access to underlying output objects
////////////////////////////////////////////////
*/
final protected OutputStream getOutputStream()
{
return mUnderlyingStream;
}
final protected Writer getWriter()
{
return mOut;
}
/*
////////////////////////////////////////////////
// Low-level (pass-through) methods
////////////////////////////////////////////////
*/
public void close()
throws IOException
{
if (mOut != null) { // just in case it's called multiple times
flush();
Writer w = mOut;
mOut = null;
mUnderlyingStream = null;
mTextWriter = null;
mAttrValueWriter = null;
char[] buf = mOutputBuffer;
mOutputBuffer = null;
mConfig.freeFullCBuffer(buf);
if (mAutoCloseOutput) {
w.close();
}
}
}
public final void flush()
throws IOException
{
if (mOut != null) {
flushBuffer();
mOut.flush();
}
}
public void writeRaw(char[] cbuf, int offset, int len)
throws IOException
{
if (mOut == null) {
return;
}
// First; is the new request small or not? If yes, needs to be buffered
if (len < mSmallWriteSize) { // yup
// Does it fit in with current buffer? If not, need to flush first
if ((mOutputPtr + len) > mOutputBufLen) {
flushBuffer();
}
System.arraycopy(cbuf, offset, mOutputBuffer, mOutputPtr, len);
mOutputPtr += len;
return;
}
// Ok, not a small request. But buffer may have existing content?
int ptr = mOutputPtr;
if (ptr > 0) {
// If it's a small chunk, need to fill enough before flushing
if (ptr < mSmallWriteSize) {
/* Also, if we are to copy any stuff, let's make sure
* that we either copy it all in one chunk, or copy
* enough for non-small chunk, flush, and output remaining
* non-small chink (former possible if chunk we were requested
* to output is only slightly over 'small' size)
*/
int needed = (mSmallWriteSize - ptr);
// Just need minimal copy:
System.arraycopy(cbuf, offset, mOutputBuffer, ptr, needed);
mOutputPtr = ptr + needed;
len -= needed;
offset += needed;
}
flushBuffer();
}
// And then we'll just write whatever we have left:
mOut.write(cbuf, offset, len);
}
public void writeRaw(String str)
throws IOException
{
if (mOut == null) {
return;
}
final int len = str.length();
// First; is the new request small or not? If yes, needs to be buffered
if (len < mSmallWriteSize) { // yup
// Does it fit in with current buffer? If not, need to flush first
if ((mOutputPtr + len) >= mOutputBufLen) {
flushBuffer();
}
str.getChars(0, len, mOutputBuffer, mOutputPtr);
mOutputPtr += len;
return;
}
// Otherwise, let's just call the main method
writeRaw(str, 0, len);
}
public void writeRaw(String str, int offset, int len)
throws IOException
{
if (mOut == null) {
return;
}
// First; is the new request small or not? If yes, needs to be buffered
if (len < mSmallWriteSize) { // yup
// Does it fit in with current buffer? If not, need to flush first
if ((mOutputPtr + len) >= mOutputBufLen) {
flushBuffer();
}
str.getChars(offset, offset+len, mOutputBuffer, mOutputPtr);
mOutputPtr += len;
return;
}
// Ok, not a small request. But buffer may have existing content?
int ptr = mOutputPtr;
if (ptr > 0) {
// If it's a small chunk, need to fill enough before flushing
if (ptr < mSmallWriteSize) {
/* Also, if we are to copy any stuff, let's make sure
* that we either copy it all in one chunk, or copy
* enough for non-small chunk, flush, and output remaining
* non-small chunk (former possible if chunk we were requested
* to output is only slightly over 'small' size)
*/
int needed = (mSmallWriteSize - ptr);
// Just need minimal copy:
str.getChars(offset, offset+needed, mOutputBuffer, ptr);
mOutputPtr = ptr + needed;
len -= needed;
offset += needed;
}
flushBuffer();
}
// And then we'll just write whatever we have left:
mOut.write(str, offset, len);
}
/*
////////////////////////////////////////////////
// "Trusted" low-level output methods
////////////////////////////////////////////////
*/
public final void writeCDataStart()
throws IOException
{
fastWriteRaw("");
}
public final void writeCommentStart()
throws IOException
{
fastWriteRaw("");
}
public final void writePIStart(String target, boolean addSpace)
throws IOException
{
fastWriteRaw('<', '?');
fastWriteRaw(target);
if (addSpace) {
fastWriteRaw(' ');
}
}
public final void writePIEnd()
throws IOException
{
fastWriteRaw('?', '>');
}
/*
////////////////////////////////////////////////
// Higher-level output methods, text output
////////////////////////////////////////////////
*/
public int writeCData(String data)
throws IOException
{
if (mCheckContent) {
int ix = verifyCDataContent(data);
if (ix >= 0) {
if (!mFixContent) { // Can we fix it?
return ix;
}
// Yes we can! (...Bob the Builder...)
writeSegmentedCData(data, ix);
return -1;
}
}
fastWriteRaw("");
return -1;
}
public int writeCData(char[] cbuf, int offset, int len)
throws IOException
{
if (mCheckContent) {
int ix = verifyCDataContent(cbuf, offset, len);
if (ix >= 0) {
if (!mFixContent) { // Can we fix it?
return ix;
}
// Yes we can! (...Bob the Builder...)
writeSegmentedCData(cbuf, offset, len, ix);
return -1;
}
}
fastWriteRaw("");
return -1;
}
public void writeCharacters(String text)
throws IOException
{
if (mOut == null) {
return;
}
if (mTextWriter != null) { // custom escaping?
mTextWriter.write(text);
return;
}
int inPtr = 0;
final int len = text.length();
int highChar = mEncHighChar;
main_loop:
while (true) {
String ent = null;
inner_loop:
while (true) {
if (inPtr >= len) {
break main_loop;
}
char c = text.charAt(inPtr++);
if (c <= HIGHEST_ENCODABLE_TEXT_CHAR) {
if (c <= 0x0020) {
if (c != ' ' && c != '\n' && c != '\t') { // fine as is
if (c == '\r') {
if (mEscapeCR) {
break inner_loop;
}
} else {
if (!mXml11 || c == 0) {
throwInvalidChar(c);
}
break inner_loop; // need quoting ok
}
}
} else if (c == '<') {
ent = "<";
break inner_loop;
} else if (c == '&') {
ent = "&";
break inner_loop;
} else if (c == '>') {
// Let's be conservative; and if there's any
// change it might be part of "]]>" quote it
if (inPtr < 2 || text.charAt(inPtr-2) == ']') {
ent = ">";
break inner_loop;
}
}
} else if (c >= highChar) {
break inner_loop;
}
if (mOutputPtr >= mOutputBufLen) {
flushBuffer();
}
mOutputBuffer[mOutputPtr++] = c;
}
if (ent != null) {
writeRaw(ent);
} else {
writeAsEntity(text.charAt(inPtr-1));
}
}
}
public void writeCharacters(char[] cbuf, int offset, int len)
throws IOException
{
if (mOut == null) {
return;
}
if (mTextWriter != null) { // custom escaping?
mTextWriter.write(cbuf, offset, len);
} else { // nope, default:
len += offset;
do {
int c = 0;
int highChar = mEncHighChar;
int start = offset;
String ent = null;
for (; offset < len; ++offset) {
c = cbuf[offset];
if (c <= HIGHEST_ENCODABLE_TEXT_CHAR) {
if (c == '<') {
ent = "<";
break;
} else if (c == '&') {
ent = "&";
break;
} else if (c == '>') {
/* Let's be conservative; and if there's any
* change it might be part of "]]>" quote it
*/
if ((offset == start) || cbuf[offset-1] == ']') {
ent = ">";
break;
}
} else if (c < 0x0020) {
if (c == '\n' || c == '\t') { // fine as is
;
} else if (c == '\r') {
if (mEscapeCR) {
break;
}
} else {
if (!mXml11 || c == 0) {
throwInvalidChar(c);
}
break; // need quoting ok
}
}
} else if (c >= highChar) {
break;
}
// otherwise ok
}
int outLen = offset - start;
if (outLen > 0) {
writeRaw(cbuf, start, outLen);
}
if (ent != null) {
writeRaw(ent);
ent = null;
} else if (offset < len) {
writeAsEntity(c);
}
} while (++offset < len);
}
}
/**
* Method that will try to output the content as specified. If
* the content passed in has embedded "--" in it, it will either
* add an intervening space between consequtive hyphens (if content
* fixing is enabled), or return the offset of the first hyphen in
* multi-hyphen sequence.
*/
public int writeComment(String data)
throws IOException
{
if (mCheckContent) {
int ix = verifyCommentContent(data);
if (ix >= 0) {
if (!mFixContent) { // Can we fix it?
return ix;
}
// Yes we can! (...Bob the Builder...)
writeSegmentedComment(data, ix);
return -1;
}
}
fastWriteRaw("");
return -1;
}
public void writeDTD(String data)
throws IOException
{
writeRaw(data);
}
public void writeDTD(String rootName, String systemId, String publicId,
String internalSubset)
throws IOException, XMLStreamException
{
fastWriteRaw(" 0) {
fastWriteRaw(' ', '[');
fastWriteRaw(internalSubset);
fastWriteRaw(']');
}
fastWriteRaw('>');
}
public void writeEntityReference(String name)
throws IOException, XMLStreamException
{
if (mCheckNames) {
verifyNameValidity(name, mNsAware);
}
fastWriteRaw('&');
fastWriteRaw(name);
fastWriteRaw(';');
}
public void writeXmlDeclaration(String version, String encoding, String standalone)
throws IOException
{
fastWriteRaw(" 0) {
fastWriteRaw(" encoding='");
fastWriteRaw(encoding);
fastWriteRaw('\'');
}
if (standalone != null) {
fastWriteRaw(" standalone='");
fastWriteRaw(standalone);
fastWriteRaw('\'');
}
fastWriteRaw('?', '>');
}
public int writePI(String target, String data)
throws IOException, XMLStreamException
{
if (mCheckNames) {
// As per namespace specs, can not have colon(s)
verifyNameValidity(target, mNsAware);
}
fastWriteRaw('<', '?');
fastWriteRaw(target);
if (data != null && data.length() > 0) {
if (mCheckContent) {
int ix = data.indexOf('?');
if (ix >= 0) {
ix = data.indexOf("?>", ix);
if (ix >= 0) {
return ix;
}
}
}
fastWriteRaw(' ');
// Data may be longer, let's call regular writeRaw method
writeRaw(data);
}
fastWriteRaw('?', '>');
return -1;
}
/*
////////////////////////////////////////////////////
// Write methods, elements
////////////////////////////////////////////////////
*/
public void writeStartTagStart(String localName)
throws IOException, XMLStreamException
{
if (mCheckNames) {
verifyNameValidity(localName, mNsAware);
}
int ptr = mOutputPtr;
int extra = (mOutputBufLen - ptr) - (1 + localName.length());
if (extra < 0) { // split on boundary, slower
fastWriteRaw('<');
fastWriteRaw(localName);
} else {
char[] buf = mOutputBuffer;
buf[ptr++] = '<';
int len = localName.length();
localName.getChars(0, len, buf, ptr);
mOutputPtr = ptr+len;
}
}
public void writeStartTagStart(String prefix, String localName)
throws IOException, XMLStreamException
{
if (prefix == null || prefix.length() == 0) { // shouldn't happen
writeStartTagStart(localName);
return;
}
if (mCheckNames) {
verifyNameValidity(prefix, mNsAware);
verifyNameValidity(localName, mNsAware);
}
int ptr = mOutputPtr;
int len = prefix.length();
int extra = (mOutputBufLen - ptr) - (2 + localName.length() + len);
if (extra < 0) { // across buffer boundary, slow case
fastWriteRaw('<');
fastWriteRaw(prefix);
fastWriteRaw(':');
fastWriteRaw(localName);
} else { // fast case, all inlined
char[] buf = mOutputBuffer;
buf[ptr++] = '<';
prefix.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = ':';
len = localName.length();
localName.getChars(0, len, buf, ptr);
mOutputPtr = ptr+len;
}
}
public void writeStartTagEnd()
throws IOException
{
fastWriteRaw('>');
}
public void writeStartTagEmptyEnd()
throws IOException
{
int ptr = mOutputPtr;
if ((ptr + 3) >= mOutputBufLen) {
if (mOut == null) {
return;
}
flushBuffer();
ptr = mOutputPtr;
}
char[] buf = mOutputBuffer;
buf[ptr++] = ' ';
buf[ptr++] = '/';
buf[ptr++] = '>';
mOutputPtr = ptr;
}
public void writeEndTag(String localName)
throws IOException
{
int ptr = mOutputPtr;
int extra = (mOutputBufLen - ptr) - (3 + localName.length());
if (extra < 0) {
fastWriteRaw('<', '/');
fastWriteRaw(localName);
fastWriteRaw('>');
} else {
char[] buf = mOutputBuffer;
buf[ptr++] = '<';
buf[ptr++] = '/';
int len = localName.length();
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '>';
mOutputPtr = ptr;
}
}
public void writeEndTag(String prefix, String localName)
throws IOException
{
if (prefix == null || prefix.length() == 0) {
writeEndTag(localName);
return;
}
int ptr = mOutputPtr;
int len = prefix.length();
int extra = (mOutputBufLen - ptr) - (4 + localName.length() + len);
if (extra < 0) {
fastWriteRaw('<', '/');
/* At this point, it is assumed caller knows that end tag
* matches with start tag, and that it (by extension) has been
* validated if and as necessary
*/
fastWriteRaw(prefix);
fastWriteRaw(':');
fastWriteRaw(localName);
fastWriteRaw('>');
} else {
char[] buf = mOutputBuffer;
buf[ptr++] = '<';
buf[ptr++] = '/';
prefix.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = ':';
len = localName.length();
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '>';
mOutputPtr = ptr;
}
}
/*
////////////////////////////////////////////////////
// Write methods, attributes/ns
////////////////////////////////////////////////////
*/
public void writeAttribute(String localName, String value)
throws IOException, XMLStreamException
{
if (mOut == null) {
return;
}
if (mCheckNames) {
verifyNameValidity(localName, mNsAware);
}
int len = localName.length();
if (((mOutputBufLen - mOutputPtr) - (3 + len)) < 0) {
fastWriteRaw(' ');
fastWriteRaw(localName);
fastWriteRaw('=', '"');
} else {
int ptr = mOutputPtr;
char[] buf = mOutputBuffer;
buf[ptr++] = ' ';
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '=';
buf[ptr++] = '"';
mOutputPtr = ptr;
}
len = (value == null) ? 0 : value.length();
if (len > 0) {
if (mAttrValueWriter != null) { // custom escaping?
mAttrValueWriter.write(value, 0, len);
} else { // nope, default
writeAttrValue(value, len);
}
}
fastWriteRaw('"');
}
public void writeAttribute(String localName, char[] value, int offset, int vlen)
throws IOException, XMLStreamException
{
if (mOut == null) {
return;
}
if (mCheckNames) {
verifyNameValidity(localName, mNsAware);
}
int len = localName.length();
if (((mOutputBufLen - mOutputPtr) - (3 + len)) < 0) {
fastWriteRaw(' ');
fastWriteRaw(localName);
fastWriteRaw('=', '"');
} else {
int ptr = mOutputPtr;
char[] buf = mOutputBuffer;
buf[ptr++] = ' ';
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '=';
buf[ptr++] = '"';
mOutputPtr = ptr;
}
if (vlen > 0) {
if (mAttrValueWriter != null) { // custom escaping?
mAttrValueWriter.write(value, offset, vlen);
} else { // nope, default
writeAttrValue(value, offset, vlen);
}
}
fastWriteRaw('"');
}
public void writeAttribute(String prefix, String localName, String value)
throws IOException, XMLStreamException
{
if (mOut == null) {
return;
}
if (mCheckNames) {
verifyNameValidity(prefix, mNsAware);
verifyNameValidity(localName, mNsAware);
}
int len = prefix.length();
if (((mOutputBufLen - mOutputPtr) - (4 + localName.length() + len)) < 0) {
fastWriteRaw(' ');
if (prefix != null && prefix.length() > 0) {
fastWriteRaw(prefix);
fastWriteRaw(':');
}
fastWriteRaw(localName);
fastWriteRaw('=', '"');
} else {
int ptr = mOutputPtr;
char[] buf = mOutputBuffer;
buf[ptr++] = ' ';
prefix.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = ':';
len = localName.length();
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '=';
buf[ptr++] = '"';
mOutputPtr = ptr;
}
len = (value == null) ? 0 : value.length();
if (len > 0) {
if (mAttrValueWriter != null) { // custom escaping?
mAttrValueWriter.write(value, 0, len);
} else { // nope, default
writeAttrValue(value, len);
}
}
fastWriteRaw('"');
}
public void writeAttribute(String prefix, String localName, char[] value, int offset, int vlen)
throws IOException, XMLStreamException
{
if (mOut == null) {
return;
}
if (mCheckNames) {
verifyNameValidity(prefix, mNsAware);
verifyNameValidity(localName, mNsAware);
}
int len = prefix.length();
if (((mOutputBufLen - mOutputPtr) - (4 + localName.length() + len)) < 0) {
fastWriteRaw(' ');
if (prefix != null && prefix.length() > 0) {
fastWriteRaw(prefix);
fastWriteRaw(':');
}
fastWriteRaw(localName);
fastWriteRaw('=', '"');
} else {
int ptr = mOutputPtr;
char[] buf = mOutputBuffer;
buf[ptr++] = ' ';
prefix.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = ':';
len = localName.length();
localName.getChars(0, len, buf, ptr);
ptr += len;
buf[ptr++] = '=';
buf[ptr++] = '"';
mOutputPtr = ptr;
}
if (vlen > 0) {
if (mAttrValueWriter != null) { // custom escaping?
mAttrValueWriter.write(value, offset, vlen);
} else { // nope, default
writeAttrValue(value, offset, vlen);
}
}
fastWriteRaw('"');
}
private final void writeAttrValue(String value, int len)
throws IOException
{
int inPtr = 0;
final char qchar = mEncQuoteChar;
int highChar = mEncHighChar;
main_loop:
while (true) { // main_loop
String ent = null;
inner_loop:
while (true) {
if (inPtr >= len) {
break main_loop;
}
char c = value.charAt(inPtr++);
if (c <= HIGHEST_ENCODABLE_ATTR_CHAR) { // special char?
if (c < 0x0020) { // tab, cr/lf need encoding too
if (c != '\n' && c != '\r' && c != '\t') {
if (!mXml11 || c == 0) {
throwInvalidChar(c);
}
}
break inner_loop; // need quoting ok
} else if (c == qchar) {
ent = mEncQuoteEntity;
break inner_loop;
} else if (c == '<') {
ent = "<";
break inner_loop;
} else if (c == '&') {
ent = "&";
break inner_loop;
}
} else if (c >= highChar) { // out of range, have to escape
break inner_loop;
}
if (mOutputPtr >= mOutputBufLen) {
flushBuffer();
}
mOutputBuffer[mOutputPtr++] = c;
}
if (ent != null) {
writeRaw(ent);
} else {
writeAsEntity(value.charAt(inPtr-1));
}
}
}
private final void writeAttrValue(char[] value, int offset, int len)
throws IOException
{
len += offset;
final char qchar = mEncQuoteChar;
int highChar = mEncHighChar;
main_loop:
while (true) { // main_loop
String ent = null;
inner_loop:
while (true) {
if (offset >= len) {
break main_loop;
}
char c = value[offset++];
if (c <= HIGHEST_ENCODABLE_ATTR_CHAR) { // special char?
if (c < 0x0020) { // tab, cr/lf need encoding too
if (c != '\n' && c != '\r' && c != '\t') {
if (!mXml11 || c == 0) {
throwInvalidChar(c);
}
}
break inner_loop; // need quoting ok
} else if (c == qchar) {
ent = mEncQuoteEntity;
break inner_loop;
} else if (c == '<') {
ent = "<";
break inner_loop;
} else if (c == '&') {
ent = "&";
break inner_loop;
}
} else if (c >= highChar) { // out of range, have to escape
break inner_loop;
}
if (mOutputPtr >= mOutputBufLen) {
flushBuffer();
}
mOutputBuffer[mOutputPtr++] = c;
}
if (ent != null) {
writeRaw(ent);
} else {
writeAsEntity(value[offset-1]);
}
}
}
/*
////////////////////////////////////////////////////
// Internal methods, buffering
////////////////////////////////////////////////////
*/
private final void flushBuffer()
throws IOException
{
if (mOutputPtr > 0 && mOut != null) {
int ptr = mOutputPtr;
// Need to update location info, to keep it in sync
mLocPastChars += ptr;
mLocRowStartOffset -= ptr;
mOutputPtr = 0;
mOut.write(mOutputBuffer, 0, ptr);
}
}
private final void fastWriteRaw(char c)
throws IOException
{
if (mOutputPtr >= mOutputBufLen) {
if (mOut == null) {
return;
}
flushBuffer();
}
mOutputBuffer[mOutputPtr++] = c;
}
private final void fastWriteRaw(char c1, char c2)
throws IOException
{
if ((mOutputPtr + 1) >= mOutputBufLen) {
if (mOut == null) {
return;
}
flushBuffer();
}
mOutputBuffer[mOutputPtr++] = c1;
mOutputBuffer[mOutputPtr++] = c2;
}
private final void fastWriteRaw(String str)
throws IOException
{
int len = str.length();
int ptr = mOutputPtr;
if ((ptr + len) >= mOutputBufLen) {
if (mOut == null) {
return;
}
/* It's even possible that String is longer than the buffer (not
* likely, possible). If so, let's just call the full
* method:
*/
if (len > mOutputBufLen) {
writeRaw(str);
return;
}
flushBuffer();
ptr = mOutputPtr;
}
str.getChars(0, len, mOutputBuffer, ptr);
mOutputPtr = ptr+len;
}
/*
////////////////////////////////////////////////////
// Internal methods, content verification/fixing
////////////////////////////////////////////////////
*/
/**
* @return Index at which a problem was found, if any; -1 if there's
* no problem.
*/
protected int verifyCDataContent(String content)
{
if (content != null && content.length() >= 3) {
int ix = content.indexOf(']');
if (ix >= 0) {
return content.indexOf("]]>", ix);
}
}
return -1;
}
protected int verifyCDataContent(char[] c, int start, int end)
{
if (c != null) {
start += 2;
/* Let's do simple optimization for search...
* (bayer-moore search algorithm)
*/
while (start < end) {
char ch = c[start];
if (ch == ']') {
++start; // let's just move by one in this case
continue;
}
if (ch == '>') { // match?
if (c[start-1] == ']'
&& c[start-2] == ']') {
return start-2;
}
}
start += 2;
}
}
return -1;
}
protected int verifyCommentContent(String content)
{
int ix = content.indexOf('-');
if (ix >= 0) {
/* actually, it's illegal to just end with '-' too, since
* that would cause invalid end marker '--->'
*/
if (ix < (content.length() - 1)) {
ix = content.indexOf("--", ix);
}
}
return ix;
}
protected void writeSegmentedCData(String content, int index)
throws IOException
{
/* It's actually fairly easy, just split "]]>" into 2 pieces;
* for each ']]>'; first one containing "]]", second one ">"
* (as long as necessary)
*/
int start = 0;
while (index >= 0) {
fastWriteRaw("");
start = index+2;
index = content.indexOf("]]>", start);
}
// Ok, then the last segment
fastWriteRaw("");
}
protected void writeSegmentedCData(char[] c, int start, int len, int index)
throws IOException
{
int end = start + len;
while (index >= 0) {
fastWriteRaw("");
start = index+2;
index = verifyCDataContent(c, start, end);
}
// Ok, then the last segment
fastWriteRaw("");
}
protected void writeSegmentedComment(String content, int index)
throws IOException
{
int len = content.length();
// First the special case (last char is hyphen):
if (index == (len-1)) {
fastWriteRaw("");
return;
}
/* Fixing comments is more difficult than that of CDATA segments';
* this because CDATA can still contain embedded ']]'s, but
* comment neither allows '--' nor ending with '-->'; which means
* that it's impossible to just split segments. Instead we'll do
* something more intrusive, and embed single spaces between all
* '--' character pairs... it's intrusive, but comments are not
* supposed to contain any data, so that should be fine (plus
* at least result is valid, unlike contents as is)
*/
fastWriteRaw("");
}
/**
* Method used to figure out which part of the Unicode char set the
* encoding can natively support. Values returned are 7, 8 and 16,
* to indicate (respectively) "ascii", "ISO-Latin" and "native Unicode".
* These just best guesses, but should work ok for the most common
* encodings.
*/
public static int guessEncodingBitSize(String enc)
{
if (enc == null || enc.length() == 0) { // let's assume default is UTF-8...
return 16;
}
// Let's see if we can find a normalized name, first:
enc = CharsetNames.normalize(enc);
// Ok, first, do we have known ones; starting with most common:
if (enc == CharsetNames.CS_UTF8) {
return 16; // meaning up to 2^16 can be represented natively
} else if (enc == CharsetNames.CS_ISO_LATIN1) {
return 8;
} else if (enc == CharsetNames.CS_US_ASCII) {
return 7;
} else if (enc == CharsetNames.CS_UTF16
|| enc == CharsetNames.CS_UTF16BE
|| enc == CharsetNames.CS_UTF16LE
|| enc == CharsetNames.CS_UTF32BE
|| enc == CharsetNames.CS_UTF32LE) {
return 16;
}
/* Above and beyond well-recognized names, it might still be
* good to have more heuristics for as-of-yet unhandled cases...
* But, it's probably easier to only assume 8-bit clean (could
* even make it just 7, let's see how this works out)
*/
return 8;
}
protected final void writeAsEntity(int c)
throws IOException
{
char[] buf = mOutputBuffer;
int ptr = mOutputPtr;
if ((ptr + 10) >= buf.length) { // &#x [up to 6 hex digits] ;
flushBuffer();
ptr = mOutputPtr;
}
buf[ptr++] = '&';
// Can use more optimal notation for 8-bit ascii stuff:
if (c < 256) {
/* Also; although not really mandatory, let's also
* use pre-defined entities where possible.
*/
if (c == '&') {
buf[ptr++] = 'a';
buf[ptr++] = 'm';
buf[ptr++] = 'p';
} else if (c == '<') {
buf[ptr++] = 'l';
buf[ptr++] = 't';
} else if (c == '>') {
buf[ptr++] = 'g';
buf[ptr++] = 't';
} else if (c == '\'') {
buf[ptr++] = 'a';
buf[ptr++] = 'p';
buf[ptr++] = 'o';
buf[ptr++] = 's';
} else if (c == '"') {
buf[ptr++] = 'q';
buf[ptr++] = 'u';
buf[ptr++] = 'o';
buf[ptr++] = 't';
} else {
buf[ptr++] = '#';;
buf[ptr++] = 'x';;
// Can use shortest quoting for tab, cr, lf:
if (c >= 16) {
int digit = (c >> 4);
buf[ptr++] = (char) ((digit < 10) ? ('0' + digit) : (('a' - 10) + digit));
c &= 0xF;
}
buf[ptr++] = (char) ((c < 10) ? ('0' + c) : (('a' - 10) + c));
}
} else {
buf[ptr++] = '#';
buf[ptr++] = 'x';
// Ok, let's write the shortest possible sequence then:
int shift = 20;
int origPtr = ptr;
do {
int digit = (c >> shift) & 0xF;
if (digit > 0 || (ptr != origPtr)) {
buf[ptr++] = (char) ((digit < 10) ? ('0' + digit) : (('a' - 10) + digit));
}
shift -= 4;
} while (shift > 0);
c &= 0xF;
buf[ptr++] = (char) ((c < 10) ? ('0' + c) : (('a' - 10) + c));
}
buf[ptr++] = ';';
mOutputPtr = ptr;
}
}