File	Doc	Category	Size	Date	Package
FastStringBuffer.java	API Doc	Java SE 5 API	43141	Fri Aug 26 14:56:04 BST 2005	com.sun.org.apache.xml.internal.utils

FastStringBuffer

• java.lang.Object

Fields Summary
static final int	DEBUG_FORCE_INIT_BITS
static boolean	DEBUG_FORCE_FIXED_CHUNKSIZE
public static final int	SUPPRESS_LEADING_WS Manifest constant: Suppress leading whitespace. This should be used when normalize-to-SAX is called for the first chunk of a multi-chunk output, or one following unsuppressed whitespace in a previous chunk.
public static final int	SUPPRESS_TRAILING_WS Manifest constant: Suppress trailing whitespace. This should be used when normalize-to-SAX is called for the last chunk of a multi-chunk output; it may have to be or'ed with SUPPRESS_LEADING_WS.
public static final int	SUPPRESS_BOTH Manifest constant: Suppress both leading and trailing whitespace. This should be used when normalize-to-SAX is called for a complete string. (I'm not wild about the name of this one. Ideas welcome.)
private static final int	CARRY_WS Manifest constant: Carry trailing whitespace of one chunk as leading whitespace of the next chunk. Used internally; I don't see any reason to make it public right now.
int	m_chunkBits Field m_chunkBits sets our chunking strategy, by saying how many bits of index can be used within a single chunk before flowing over to the next chunk. For example, if m_chunkbits is set to 15, each chunk can contain up to 2^15 (32K) characters
int	m_maxChunkBits Field m_maxChunkBits affects our chunk-growth strategy, by saying what the largest permissible chunk size is in this particular FastStringBuffer hierarchy.
int	m_rebundleBits Field m_rechunkBits affects our chunk-growth strategy, by saying how many chunks should be allocated at one size before we encapsulate them into the first chunk of the next size up. For example, if m_rechunkBits is set to 3, then after 8 chunks at a given size we will rebundle them as the first element of a FastStringBuffer using a chunk size 8 times larger (chunkBits shifted left three bits).
int	m_chunkSize Field m_chunkSize establishes the maximum size of one chunk of the array as 2**chunkbits characters. (Which may also be the minimum size if we aren't tuning for storage)
int	m_chunkMask Field m_chunkMask is m_chunkSize-1 -- in other words, m_chunkBits worth of low-order '1' bits, useful for shift-and-mask addressing within the chunks.
char[]	m_array Field m_array holds the string buffer's text contents, using an array-of-arrays. Note that this array, and the arrays it contains, may be reallocated when necessary in order to allow the buffer to grow; references to them should be considered to be invalidated after any append. However, the only time these arrays are directly exposed is in the sendSAXcharacters call.
int	m_lastChunk Field m_lastChunk is an index into m_array[], pointing to the last chunk of the Chunked Array currently in use. Note that additional chunks may actually be allocated, eg if the FastStringBuffer had previously been truncated or if someone issued an ensureSpace request. The insertion point for append operations is addressed by the combination of m_lastChunk and m_firstFree.
int	m_firstFree Field m_firstFree is an index into m_array[m_lastChunk][], pointing to the first character in the Chunked Array which is not part of the FastStringBuffer's current content. Since m_array[][] is zero-based, the length of that content can be calculated as (m_lastChunk<
FastStringBuffer	m_innerFSB Field m_innerFSB, when non-null, is a FastStringBuffer whose total length equals m_chunkSize, and which replaces m_array[0]. This allows building a hierarchy of FastStringBuffers, where early appends use a smaller chunkSize (for less wasted memory overhead) but later ones use a larger chunkSize (for less heap activity overhead).
static final char[]	SINGLE_SPACE

Constructors Summary
public FastStringBuffer(int initChunkBits, int maxChunkBits, int rebundleBits) Construct a FastStringBuffer, with allocation policy as per parameters. For coding convenience, I've expressed both allocation sizes in terms of a number of bits. That's needed for the final size of a chunk, to permit fast and efficient shift-and-mask addressing. It's less critical for the inital size, and may be reconsidered. An alternative would be to accept integer sizes and round to powers of two; that really doesn't seem to buy us much, if anything. param initChunkBits Length in characters of the initial allocation of a chunk, expressed in log-base-2. (That is, 10 means allocate 1024 characters.) Later chunks will use larger allocation units, to trade off allocation speed of large document against storage efficiency of small ones. param maxChunkBits Number of character-offset bits that should be used for addressing within a chunk. Maximum length of a chunk is 2^chunkBits characters. param rebundleBits Number of character-offset bits that addressing should advance before we attempt to take a step from initChunkBits to maxChunkBits if(DEBUG_FORCE_INIT_BITS!=0) initChunkBits=DEBUG_FORCE_INIT_BITS; // %REVIEW% // Should this force to larger value, or smaller? Smaller less efficient, but if // someone requested variable mode it's because they care about storage space. // On the other hand, given the other changes I'm making, odds are that we should // adopt the larger size. Dither, dither, dither... This is just stopgap workaround // anyway; we need a permanant solution. // if(DEBUG_FORCE_FIXED_CHUNKSIZE) maxChunkBits=initChunkBits; //if(DEBUG_FORCE_FIXED_CHUNKSIZE) initChunkBits=maxChunkBits; m_array = new char[16][]; // Don't bite off more than we're prepared to swallow! if (initChunkBits > maxChunkBits) initChunkBits = maxChunkBits; m_chunkBits = initChunkBits; m_maxChunkBits = maxChunkBits; m_rebundleBits = rebundleBits; m_chunkSize = 1 << (initChunkBits); m_chunkMask = m_chunkSize - 1; m_array[0] = new char[m_chunkSize];
public FastStringBuffer(int initChunkBits, int maxChunkBits) Construct a FastStringBuffer, using a default rebundleBits value. NEEDSDOC @param initChunkBits NEEDSDOC @param maxChunkBits this(initChunkBits, maxChunkBits, 2);
private FastStringBuffer(FastStringBuffer source) Encapsulation c'tor. After this is called, the source FastStringBuffer will be reset to use the new object as its m_innerFSB, and will have had its chunk size reset appropriately. IT SHOULD NEVER BE CALLED EXCEPT WHEN source.length()==1<<(source.m_chunkBits+source.m_rebundleBits) NEEDSDOC @param source // Copy existing information into new encapsulation m_chunkBits = source.m_chunkBits; m_maxChunkBits = source.m_maxChunkBits; m_rebundleBits = source.m_rebundleBits; m_chunkSize = source.m_chunkSize; m_chunkMask = source.m_chunkMask; m_array = source.m_array; m_innerFSB = source.m_innerFSB; // These have to be adjusted because we're calling just at the time // when we would be about to allocate another chunk m_lastChunk = source.m_lastChunk - 1; m_firstFree = source.m_chunkSize; // Establish capsule as the Inner FSB, reset chunk sizes/addressing source.m_array = new char[16][]; source.m_innerFSB = this; // Since we encapsulated just as we were about to append another // chunk, return ready to create the chunk after the innerFSB // -- 1, not 0. source.m_lastChunk = 1; source.m_firstFree = 0; source.m_chunkBits += m_rebundleBits; source.m_chunkSize = 1 << (source.m_chunkBits); source.m_chunkMask = source.m_chunkSize - 1;
public FastStringBuffer(int initChunkBits) Construct a FastStringBuffer, using default maxChunkBits and rebundleBits values. ISSUE: Should this call assert initial size, or fixed size? Now configured as initial, with a default for fixed. param NEEDSDOC @param initChunkBits this(initChunkBits, 15, 2);
public FastStringBuffer() Construct a FastStringBuffer, using a default allocation policy. // 10 bits is 1K. 15 bits is 32K. Remember that these are character // counts, so actual memory allocation unit is doubled for UTF-16 chars. // // For reference: In the original FastStringBuffer, we simply // overallocated by blocksize (default 1KB) on each buffer-growth. this(10, 15, 2);

Methods Summary
public final void	append(char value) Append a single character onto the FastStringBuffer, growing the storage if necessary. NOTE THAT after calling append(), previously obtained references to m_array[][] may no longer be valid.... though in fact they should be in this instance. param value character to be appended. char[] chunk; // We may have preallocated chunks. If so, all but last should // be at full size. boolean lastchunk = (m_lastChunk + 1 == m_array.length); if (m_firstFree < m_chunkSize) // Simplified test single-character-fits chunk = m_array[m_lastChunk]; else { // Extend array? int i = m_array.length; if (m_lastChunk + 1 == i) { char[][] newarray = new char[i + 16][]; System.arraycopy(m_array, 0, newarray, 0, i); m_array = newarray; } // Advance one chunk chunk = m_array[++m_lastChunk]; if (chunk == null) { // Hierarchical encapsulation if (m_lastChunk == 1 << m_rebundleBits && m_chunkBits < m_maxChunkBits) { // Should do all the work of both encapsulating // existing data and establishing new sizes/offsets m_innerFSB = new FastStringBuffer(this); } // Add a chunk. chunk = m_array[m_lastChunk] = new char[m_chunkSize]; } m_firstFree = 0; } // Space exists in the chunk. Append the character. chunk[m_firstFree++] = value;
public final void	append(java.lang.String value) Append the contents of a String onto the FastStringBuffer, growing the storage if necessary. NOTE THAT after calling append(), previously obtained references to m_array[] may no longer be valid. param value String whose contents are to be appended. if (value == null) return; int strlen = value.length(); if (0 == strlen) return; int copyfrom = 0; char[] chunk = m_array[m_lastChunk]; int available = m_chunkSize - m_firstFree; // Repeat while data remains to be copied while (strlen > 0) { // Copy what fits if (available > strlen) available = strlen; value.getChars(copyfrom, copyfrom + available, m_array[m_lastChunk], m_firstFree); strlen -= available; copyfrom += available; // If there's more left, allocate another chunk and continue if (strlen > 0) { // Extend array? int i = m_array.length; if (m_lastChunk + 1 == i) { char[][] newarray = new char[i + 16][]; System.arraycopy(m_array, 0, newarray, 0, i); m_array = newarray; } // Advance one chunk chunk = m_array[++m_lastChunk]; if (chunk == null) { // Hierarchical encapsulation if (m_lastChunk == 1 << m_rebundleBits && m_chunkBits < m_maxChunkBits) { // Should do all the work of both encapsulating // existing data and establishing new sizes/offsets m_innerFSB = new FastStringBuffer(this); } // Add a chunk. chunk = m_array[m_lastChunk] = new char[m_chunkSize]; } available = m_chunkSize; m_firstFree = 0; } } // Adjust the insert point in the last chunk, when we've reached it. m_firstFree += available;
public final void	append(java.lang.StringBuffer value) Append the contents of a StringBuffer onto the FastStringBuffer, growing the storage if necessary. NOTE THAT after calling append(), previously obtained references to m_array[] may no longer be valid. param value StringBuffer whose contents are to be appended. if (value == null) return; int strlen = value.length(); if (0 == strlen) return; int copyfrom = 0; char[] chunk = m_array[m_lastChunk]; int available = m_chunkSize - m_firstFree; // Repeat while data remains to be copied while (strlen > 0) { // Copy what fits if (available > strlen) available = strlen; value.getChars(copyfrom, copyfrom + available, m_array[m_lastChunk], m_firstFree); strlen -= available; copyfrom += available; // If there's more left, allocate another chunk and continue if (strlen > 0) { // Extend array? int i = m_array.length; if (m_lastChunk + 1 == i) { char[][] newarray = new char[i + 16][]; System.arraycopy(m_array, 0, newarray, 0, i); m_array = newarray; } // Advance one chunk chunk = m_array[++m_lastChunk]; if (chunk == null) { // Hierarchical encapsulation if (m_lastChunk == 1 << m_rebundleBits && m_chunkBits < m_maxChunkBits) { // Should do all the work of both encapsulating // existing data and establishing new sizes/offsets m_innerFSB = new FastStringBuffer(this); } // Add a chunk. chunk = m_array[m_lastChunk] = new char[m_chunkSize]; } available = m_chunkSize; m_firstFree = 0; } } // Adjust the insert point in the last chunk, when we've reached it. m_firstFree += available;
public final void	append(char[] chars, int start, int length) Append part of the contents of a Character Array onto the FastStringBuffer, growing the storage if necessary. NOTE THAT after calling append(), previously obtained references to m_array[] may no longer be valid. param chars character array from which data is to be copied param start offset in chars of first character to be copied, zero-based. param length number of characters to be copied int strlen = length; if (0 == strlen) return; int copyfrom = start; char[] chunk = m_array[m_lastChunk]; int available = m_chunkSize - m_firstFree; // Repeat while data remains to be copied while (strlen > 0) { // Copy what fits if (available > strlen) available = strlen; System.arraycopy(chars, copyfrom, m_array[m_lastChunk], m_firstFree, available); strlen -= available; copyfrom += available; // If there's more left, allocate another chunk and continue if (strlen > 0) { // Extend array? int i = m_array.length; if (m_lastChunk + 1 == i) { char[][] newarray = new char[i + 16][]; System.arraycopy(m_array, 0, newarray, 0, i); m_array = newarray; } // Advance one chunk chunk = m_array[++m_lastChunk]; if (chunk == null) { // Hierarchical encapsulation if (m_lastChunk == 1 << m_rebundleBits && m_chunkBits < m_maxChunkBits) { // Should do all the work of both encapsulating // existing data and establishing new sizes/offsets m_innerFSB = new FastStringBuffer(this); } // Add a chunk. chunk = m_array[m_lastChunk] = new char[m_chunkSize]; } available = m_chunkSize; m_firstFree = 0; } } // Adjust the insert point in the last chunk, when we've reached it. m_firstFree += available;
public final void	append(com.sun.org.apache.xml.internal.utils.FastStringBuffer value) Append the contents of another FastStringBuffer onto this FastStringBuffer, growing the storage if necessary. NOTE THAT after calling append(), previously obtained references to m_array[] may no longer be valid. param value FastStringBuffer whose contents are to be appended. // Complicating factor here is that the two buffers may use // different chunk sizes, and even if they're the same we're // probably on a different alignment due to previously appended // data. We have to work through the source in bite-sized chunks. if (value == null) return; int strlen = value.length(); if (0 == strlen) return; int copyfrom = 0; char[] chunk = m_array[m_lastChunk]; int available = m_chunkSize - m_firstFree; // Repeat while data remains to be copied while (strlen > 0) { // Copy what fits if (available > strlen) available = strlen; int sourcechunk = (copyfrom + value.m_chunkSize - 1) >>> value.m_chunkBits; int sourcecolumn = copyfrom & value.m_chunkMask; int runlength = value.m_chunkSize - sourcecolumn; if (runlength > available) runlength = available; System.arraycopy(value.m_array[sourcechunk], sourcecolumn, m_array[m_lastChunk], m_firstFree, runlength); if (runlength != available) System.arraycopy(value.m_array[sourcechunk + 1], 0, m_array[m_lastChunk], m_firstFree + runlength, available - runlength); strlen -= available; copyfrom += available; // If there's more left, allocate another chunk and continue if (strlen > 0) { // Extend array? int i = m_array.length; if (m_lastChunk + 1 == i) { char[][] newarray = new char[i + 16][]; System.arraycopy(m_array, 0, newarray, 0, i); m_array = newarray; } // Advance one chunk chunk = m_array[++m_lastChunk]; if (chunk == null) { // Hierarchical encapsulation if (m_lastChunk == 1 << m_rebundleBits && m_chunkBits < m_maxChunkBits) { // Should do all the work of both encapsulating // existing data and establishing new sizes/offsets m_innerFSB = new FastStringBuffer(this); } // Add a chunk. chunk = m_array[m_lastChunk] = new char[m_chunkSize]; } available = m_chunkSize; m_firstFree = 0; } } // Adjust the insert point in the last chunk, when we've reached it. m_firstFree += available;
public char	charAt(int pos) Get a single character from the string buffer. param pos character position requested. return A character from the requested position. int startChunk = pos >>> m_chunkBits; if (startChunk == 0 && m_innerFSB != null) return m_innerFSB.charAt(pos & m_chunkMask); else return m_array[startChunk][pos & m_chunkMask];
private void	getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin) Copies characters from this string into the destination character array. param srcBegin index of the first character in the string to copy. param srcEnd index after the last character in the string to copy. param dst the destination array. param dstBegin the start offset in the destination array. exception IndexOutOfBoundsException If any of the following is true: srcBegin is negative. srcBegin is greater than srcEnd srcEnd is greater than the length of this string dstBegin is negative dstBegin+(srcEnd-srcBegin) is larger than dst.length exception NullPointerException if dst is null // %TBD% Joe needs to write this function. Make public when implemented.
protected java.lang.String	getOneChunkString(int startChunk, int startColumn, int length) return new String(m_array[startChunk], startColumn, length);
public java.lang.String	getString(int start, int length) param start Offset of first character in the range. param length Number of characters to send. return a new String object initialized from the specified range of characters. int startColumn = start & m_chunkMask; int startChunk = start >>> m_chunkBits; if (startColumn + length < m_chunkMask && m_innerFSB == null) { return getOneChunkString(startChunk, startColumn, length); } return getString(new StringBuffer(length), startChunk, startColumn, length).toString();
java.lang.StringBuffer	getString(java.lang.StringBuffer sb, int start, int length) param sb StringBuffer to be appended to param start Offset of first character in the range. param length Number of characters to send. return sb with the requested text appended to it return getString(sb, start >>> m_chunkBits, start & m_chunkMask, length);
java.lang.StringBuffer	getString(java.lang.StringBuffer sb, int startChunk, int startColumn, int length) Internal support for toString() and getString(). PLEASE NOTE SIGNATURE CHANGE from earlier versions; it now appends into and returns a StringBuffer supplied by the caller. This simplifies m_innerFSB support. Note that this operation has been somewhat deoptimized by the shift to a chunked array, as there is no factory method to produce a String object directly from an array of arrays and hence a double copy is needed. By presetting length we hope to minimize the heap overhead of building the intermediate StringBuffer. (It really is a pity that Java didn't design String as a final subclass of MutableString, rather than having StringBuffer be a separate hierarchy. We'd avoid a lot of double-buffering.) param sb param startChunk param startColumn param length return the contents of the FastStringBuffer as a standard Java string. int stop = (startChunk << m_chunkBits) + startColumn + length; int stopChunk = stop >>> m_chunkBits; int stopColumn = stop & m_chunkMask; // Factored out //StringBuffer sb=new StringBuffer(length); for (int i = startChunk; i < stopChunk; ++i) { if (i == 0 && m_innerFSB != null) m_innerFSB.getString(sb, startColumn, m_chunkSize - startColumn); else sb.append(m_array[i], startColumn, m_chunkSize - startColumn); startColumn = 0; // after first chunk } if (stopChunk == 0 && m_innerFSB != null) m_innerFSB.getString(sb, startColumn, stopColumn - startColumn); else if (stopColumn > startColumn) sb.append(m_array[stopChunk], startColumn, stopColumn - startColumn); return sb;
public boolean	isWhitespace(int start, int length) return true if the specified range of characters are all whitespace, as defined by XMLCharacterRecognizer. CURRENTLY DOES NOT CHECK FOR OUT-OF-RANGE. param start Offset of first character in the range. param length Number of characters to send. int sourcechunk = start >>> m_chunkBits; int sourcecolumn = start & m_chunkMask; int available = m_chunkSize - sourcecolumn; boolean chunkOK; while (length > 0) { int runlength = (length <= available) ? length : available; if (sourcechunk == 0 && m_innerFSB != null) chunkOK = m_innerFSB.isWhitespace(sourcecolumn, runlength); else chunkOK = com.sun.org.apache.xml.internal.utils.XMLCharacterRecognizer.isWhiteSpace( m_array[sourcechunk], sourcecolumn, runlength); if (!chunkOK) return false; length -= runlength; ++sourcechunk; sourcecolumn = 0; available = m_chunkSize; } return true;
public final int	length() Get the length of the list. Synonym for size(). return the number of characters in the FastStringBuffer's content. return (m_lastChunk << m_chunkBits) + m_firstFree;
public final void	reset() Discard the content of the FastStringBuffer, and most of the memory that was allocated by it, restoring the initial state. Note that this may eventually be different from setLength(0), which see. m_lastChunk = 0; m_firstFree = 0; // Recover the original chunk size FastStringBuffer innermost = this; while (innermost.m_innerFSB != null) { innermost = innermost.m_innerFSB; } m_chunkBits = innermost.m_chunkBits; m_chunkSize = innermost.m_chunkSize; m_chunkMask = innermost.m_chunkMask; // Discard the hierarchy m_innerFSB = null; m_array = new char[16][0]; m_array[0] = new char[m_chunkSize];
public int	sendNormalizedSAXcharacters(org.xml.sax.ContentHandler ch, int start, int length) Sends the specified range of characters as one or more SAX characters() events, normalizing the characters according to XSLT rules. param ch SAX ContentHandler object to receive the event. param start Offset of first character in the range. param length Number of characters to send. return normalization status to apply to next chunk (because we may have been called recursively to process an inner FSB): 0 if this output did not end in retained whitespace, and thus whitespace at the start of the following chunk (if any) should be converted to a single space. SUPPRESS_LEADING_WS if this output ended in retained whitespace, and thus whitespace at the start of the following chunk (if any) should be completely suppressed. exception org.xml.sax.SAXException may be thrown by handler's characters() method. // This call always starts at the beginning of the // string being written out, either because it was called directly or // because it was an m_innerFSB recursion. This is important since // it gives us a well-known initial state for this flag: int stateForNextChunk=SUPPRESS_LEADING_WS; int stop = start + length; int startChunk = start >>> m_chunkBits; int startColumn = start & m_chunkMask; int stopChunk = stop >>> m_chunkBits; int stopColumn = stop & m_chunkMask; for (int i = startChunk; i < stopChunk; ++i) { if (i == 0 && m_innerFSB != null) stateForNextChunk= m_innerFSB.sendNormalizedSAXcharacters(ch, startColumn, m_chunkSize - startColumn); else stateForNextChunk= sendNormalizedSAXcharacters(m_array[i], startColumn, m_chunkSize - startColumn, ch,stateForNextChunk); startColumn = 0; // after first chunk } // Last, or only, chunk if (stopChunk == 0 && m_innerFSB != null) stateForNextChunk= // %REVIEW% Is this update really needed? m_innerFSB.sendNormalizedSAXcharacters(ch, startColumn, stopColumn - startColumn); else if (stopColumn > startColumn) { stateForNextChunk= // %REVIEW% Is this update really needed? sendNormalizedSAXcharacters(m_array[stopChunk], startColumn, stopColumn - startColumn, ch, stateForNextChunk | SUPPRESS_TRAILING_WS); } return stateForNextChunk;
static int	sendNormalizedSAXcharacters(char[] ch, int start, int length, org.xml.sax.ContentHandler handler, int edgeTreatmentFlags) Internal method to directly normalize and dispatch the character array. This version is aware of the fact that it may be called several times in succession if the data is made up of multiple "chunks", and thus must actively manage the handling of leading and trailing whitespace. Note: The recursion is due to the possible recursion of inner FSBs. param ch The characters from the XML document. param start The start position in the array. param length The number of characters to read from the array. param handler SAX ContentHandler object to receive the event. param edgeTreatmentFlags How leading/trailing spaces should be handled. This is a bitfield contining two flags, bitwise-ORed together: SUPPRESS_LEADING_WS When false, causes leading whitespace to be converted to a single space; when true, causes it to be discarded entirely. Should be set TRUE for the first chunk, and (in multi-chunk output) whenever the previous chunk ended in retained whitespace. SUPPRESS_TRAILING_WS When false, causes trailing whitespace to be converted to a single space; when true, causes it to be discarded entirely. Should be set TRUE for the last or only chunk. return normalization status, as in the edgeTreatmentFlags parameter: 0 if this output did not end in retained whitespace, and thus whitespace at the start of the following chunk (if any) should be converted to a single space. SUPPRESS_LEADING_WS if this output ended in retained whitespace, and thus whitespace at the start of the following chunk (if any) should be completely suppressed. exception org.xml.sax.SAXException Any SAX exception, possibly wrapping another exception. boolean processingLeadingWhitespace = ((edgeTreatmentFlags & SUPPRESS_LEADING_WS) != 0); boolean seenWhitespace = ((edgeTreatmentFlags & CARRY_WS) != 0); boolean suppressTrailingWhitespace = ((edgeTreatmentFlags & SUPPRESS_TRAILING_WS) != 0); int currPos = start; int limit = start+length; // Strip any leading spaces first, if required if (processingLeadingWhitespace) { for (; currPos < limit && XMLCharacterRecognizer.isWhiteSpace(ch[currPos]); currPos++) { } // If we've only encountered leading spaces, the // current state remains unchanged if (currPos == limit) { return edgeTreatmentFlags; } } // If we get here, there are no more leading spaces to strip while (currPos < limit) { int startNonWhitespace = currPos; // Grab a chunk of non-whitespace characters for (; currPos < limit && !XMLCharacterRecognizer.isWhiteSpace(ch[currPos]); currPos++) { } // Non-whitespace seen - emit them, along with a single // space for any preceding whitespace characters if (startNonWhitespace != currPos) { if (seenWhitespace) { handler.characters(SINGLE_SPACE, 0, 1); seenWhitespace = false; } handler.characters(ch, startNonWhitespace, currPos - startNonWhitespace); } int startWhitespace = currPos; // Consume any whitespace characters for (; currPos < limit && XMLCharacterRecognizer.isWhiteSpace(ch[currPos]); currPos++) { } if (startWhitespace != currPos) { seenWhitespace = true; } } return (seenWhitespace ? CARRY_WS : 0) | (edgeTreatmentFlags & SUPPRESS_TRAILING_WS);
public static void	sendNormalizedSAXcharacters(char[] ch, int start, int length, org.xml.sax.ContentHandler handler) Directly normalize and dispatch the character array. param ch The characters from the XML document. param start The start position in the array. param length The number of characters to read from the array. param handler SAX ContentHandler object to receive the event. exception org.xml.sax.SAXException Any SAX exception, possibly wrapping another exception. sendNormalizedSAXcharacters(ch, start, length, handler, SUPPRESS_BOTH);
public void	sendSAXComment(org.xml.sax.ext.LexicalHandler ch, int start, int length) Sends the specified range of characters as sax Comment. Note that, unlike sendSAXcharacters, this has to be done as a single call to LexicalHandler#comment. param ch SAX LexicalHandler object to receive the event. param start Offset of first character in the range. param length Number of characters to send. exception org.xml.sax.SAXException may be thrown by handler's characters() method. // %OPT% Do it this way for now... String comment = getString(start, length); ch.comment(comment.toCharArray(), 0, length);
public void	sendSAXcharacters(org.xml.sax.ContentHandler ch, int start, int length) Sends the specified range of characters as one or more SAX characters() events. Note that the buffer reference passed to the ContentHandler may be invalidated if the FastStringBuffer is edited; it's the user's responsibility to manage access to the FastStringBuffer to prevent this problem from arising. Note too that there is no promise that the output will be sent as a single call. As is always true in SAX, one logical string may be split across multiple blocks of memory and hence delivered as several successive events. param ch SAX ContentHandler object to receive the event. param start Offset of first character in the range. param length Number of characters to send. exception org.xml.sax.SAXException may be thrown by handler's characters() method. int startChunk = start >>> m_chunkBits; int startColumn = start & m_chunkMask; if (startColumn + length < m_chunkMask && m_innerFSB == null) { ch.characters(m_array[startChunk], startColumn, length); return; } int stop = start + length; int stopChunk = stop >>> m_chunkBits; int stopColumn = stop & m_chunkMask; for (int i = startChunk; i < stopChunk; ++i) { if (i == 0 && m_innerFSB != null) m_innerFSB.sendSAXcharacters(ch, startColumn, m_chunkSize - startColumn); else ch.characters(m_array[i], startColumn, m_chunkSize - startColumn); startColumn = 0; // after first chunk } // Last, or only, chunk if (stopChunk == 0 && m_innerFSB != null) m_innerFSB.sendSAXcharacters(ch, startColumn, stopColumn - startColumn); else if (stopColumn > startColumn) { ch.characters(m_array[stopChunk], startColumn, stopColumn - startColumn); }
public final void	setLength(int l) Directly set how much of the FastStringBuffer's storage is to be considered part of its content. This is a fast but hazardous operation. It is not protected against negative values, or values greater than the amount of storage currently available... and even if additional storage does exist, its contents are unpredictable. The only safe use for our setLength() is to truncate the FastStringBuffer to a shorter string. param l New length. If l<0 or l>=getLength(), this operation will not report an error but future operations will almost certainly fail. m_lastChunk = l >>> m_chunkBits; if (m_lastChunk == 0 && m_innerFSB != null) { // Replace this FSB with the appropriate inner FSB, truncated m_innerFSB.setLength(l, this); } else { m_firstFree = l & m_chunkMask; // There's an edge case if l is an exact multiple of m_chunkBits, which risks leaving // us pointing at the start of a chunk which has not yet been allocated. Rather than // pay the cost of dealing with that in the append loops (more scattered and more // inner-loop), we correct it here by moving to the safe side of that // line -- as we would have left the indexes had we appended up to that point. if(m_firstFree==0 && m_lastChunk>0) { --m_lastChunk; m_firstFree=m_chunkSize; } }
private final void	setLength(int l, com.sun.org.apache.xml.internal.utils.FastStringBuffer rootFSB) Subroutine for the public setLength() method. Deals with the fact that truncation may require restoring one of the innerFSBs NEEDSDOC @param l NEEDSDOC @param rootFSB m_lastChunk = l >>> m_chunkBits; if (m_lastChunk == 0 && m_innerFSB != null) { m_innerFSB.setLength(l, rootFSB); } else { // Undo encapsulation -- pop the innerFSB data back up to root. // Inefficient, but attempts to keep the code simple. rootFSB.m_chunkBits = m_chunkBits; rootFSB.m_maxChunkBits = m_maxChunkBits; rootFSB.m_rebundleBits = m_rebundleBits; rootFSB.m_chunkSize = m_chunkSize; rootFSB.m_chunkMask = m_chunkMask; rootFSB.m_array = m_array; rootFSB.m_innerFSB = m_innerFSB; rootFSB.m_lastChunk = m_lastChunk; // Finally, truncate this sucker. rootFSB.m_firstFree = l & m_chunkMask; }
public final int	size() Get the length of the list. Synonym for length(). return the number of characters in the FastStringBuffer's content. return (m_lastChunk << m_chunkBits) + m_firstFree;
public final java.lang.String	toString() Note that this operation has been somewhat deoptimized by the shift to a chunked array, as there is no factory method to produce a String object directly from an array of arrays and hence a double copy is needed. By using ensureCapacity we hope to minimize the heap overhead of building the intermediate StringBuffer. (It really is a pity that Java didn't design String as a final subclass of MutableString, rather than having StringBuffer be a separate hierarchy. We'd avoid a lot of double-buffering.) return the contents of the FastStringBuffer as a standard Java string. int length = (m_lastChunk << m_chunkBits) + m_firstFree; return getString(new StringBuffer(length), 0, 0, length).toString();