com.ctc.wstx.util

Class TextBuffer

java.lang.Object

com.ctc.wstx.util.TextBuffer

public final class TextBuffer
extends Object

TextBuffer is a class similar to StringBuilder, with following differences:

• TextBuffer uses segments character arrays, to avoid having to do additional array copies when array is not big enough. This means that only reallocating that is necessary is done only once -- if and when caller wants to access contents in a linear array (char[], String).
• TextBuffer is not synchronized.

Over time more and more cruft has accumulated here, mostly to support efficient access to collected text. Since access is easiest to do efficiently using callbacks, this class now needs to known interfaces of SAX classes and validators.

Notes about usage: for debugging purposes, it's suggested to use toString() method, as opposed to contentsAsArray() or contentsAsString(). Internally resulting code paths may or may not be different, WRT caching.

Author:

Tatu Saloranta

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_INDENT_SPACES
static int	MAX_INDENT_TABS

Method Summary

Methods

Modifier and Type	Method and Description
void	append(char c)
void	append(char[] c, int start, int len)
void	append(String str)
char[]	contentsAsArray()
String	contentsAsString()
StringBuilder	contentsAsStringBuilder(int extraSpace) Similar to contentsAsString(), but constructs a StringBuilder for further appends.
int	contentsToArray(int srcStart, char[] dst, int dstStart, int len)
void	contentsToStringBuilder(StringBuilder sb)
static TextBuffer	createRecyclableBuffer(ReaderConfig cfg)
static TextBuffer	createTemporaryBuffer()
void	decode(org.codehaus.stax2.typed.TypedValueDecoder tvd) Generic pass-through method which call given decoder with accumulated data
int	decodeElements(org.codehaus.stax2.typed.TypedArrayDecoder tad, InputProblemReporter rep) Pass-through decode method called to find find the next token, decode it, and repeat the process as long as there are more tokens and the array decoder accepts more entries.
boolean	endsWith(String str) Method that can be used to check if the contents of the buffer end in specified String.
void	ensureNotShared() Method called to make sure that buffer is not using shared input buffer; if it is, it will copy such contents to private buffer.
boolean	equalsString(String str) Note: it is assumed that this method is not used often enough to be a bottleneck, or for long segments.
char[]	finishCurrentSegment()
void	fireDtdCommentEvent(DTDEventListener l)
void	fireSaxCharacterEvents(ContentHandler h)
void	fireSaxCommentEvent(LexicalHandler h)
void	fireSaxSpaceEvents(ContentHandler h)
char[]	getCurrentSegment()
int	getCurrentSegmentSize()
char[]	getTextBuffer()
int	getTextStart()
void	initBinaryChunks(org.codehaus.stax2.typed.Base64Variant v, org.codehaus.stax2.ri.typed.CharArrayBase64Decoder dec, boolean firstChunk) Method that needs to be called to configure given base64 decoder with textual contents collected by this buffer.
boolean	isAllWhitespace()
int	rawContentsTo(Writer w) Method that will stream contents of this buffer into specified Writer.
Reader	rawContentsViaReader()
void	recycle(boolean force) Method called to indicate that the underlying buffers should now be recycled if they haven't yet been recycled.
void	resetInitialized() Method called to make sure there is a non-shared segment to use, without appending any content yet.
void	resetWithCopy(char[] buf, int start, int len)
void	resetWithEmpty() Method called to clear out any content text buffer may have, and initializes buffer to use non-shared data.
void	resetWithEmptyString() Similar to resetWithEmpty(), but actively marks current text content to be empty string (whereas former method leaves content as undefined).
void	resetWithIndentation(int indCharCount, char indChar)
void	resetWithShared(char[] buf, int start, int len) Method called to initialize the buffer with a shared copy of data; this means that buffer will just have pointers to actual data.
void	setCurrentLength(int len)
int	size()
String	toString() Note: calling this method may not be as efficient as calling contentsAsString(), since it's not guaranteed that resulting String is cached.
void	unshare(int needExtra) Method called if/when we need to append content when we have been initialized to use shared buffer.
void	validateText(org.codehaus.stax2.validation.XMLValidator vld, boolean lastSegment)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

MAX_INDENT_SPACES

public static final int MAX_INDENT_SPACES

See Also:

Constant Field Values

MAX_INDENT_TABS

public static final int MAX_INDENT_TABS

See Also:

Constant Field Values

Method Detail

createRecyclableBuffer

public static TextBuffer createRecyclableBuffer(ReaderConfig cfg)

createTemporaryBuffer

public static TextBuffer createTemporaryBuffer()

recycle

public void recycle(boolean force)

Method called to indicate that the underlying buffers should now be recycled if they haven't yet been recycled. Although caller can still use this text buffer, it is not advisable to call this method if that is likely, since next time a buffer is needed, buffers need to reallocated. Note: calling this method automatically also clears contents of the buffer.

resetWithEmpty

public void resetWithEmpty()

Method called to clear out any content text buffer may have, and initializes buffer to use non-shared data.

resetWithEmptyString

public void resetWithEmptyString()

Similar to resetWithEmpty(), but actively marks current text content to be empty string (whereas former method leaves content as undefined).

resetWithShared

public void resetWithShared(char[] buf,
                   int start,
                   int len)

Method called to initialize the buffer with a shared copy of data; this means that buffer will just have pointers to actual data. It also means that if anything is to be appended to the buffer, it will first have to unshare it (make a local copy).

resetWithCopy

public void resetWithCopy(char[] buf,
                 int start,
                 int len)

resetInitialized

public void resetInitialized()

Method called to make sure there is a non-shared segment to use, without appending any content yet.

resetWithIndentation

public void resetWithIndentation(int indCharCount,
                        char indChar)

size

public int size()

Returns:

Number of characters currently stored by this collector

getTextStart

public int getTextStart()

getTextBuffer

public char[] getTextBuffer()

decode

public void decode(org.codehaus.stax2.typed.TypedValueDecoder tvd)
            throws IllegalArgumentException

Generic pass-through method which call given decoder with accumulated data

Throws:

IllegalArgumentException

decodeElements

public int decodeElements(org.codehaus.stax2.typed.TypedArrayDecoder tad,
                 InputProblemReporter rep)
                   throws org.codehaus.stax2.typed.TypedXMLStreamException

Pass-through decode method called to find find the next token, decode it, and repeat the process as long as there are more tokens and the array decoder accepts more entries. All tokens processed will be "consumed", such that they will not be visible via buffer.

Returns:

Number of tokens decoded; 0 means that no (more) tokens were found from this buffer.

Throws:

org.codehaus.stax2.typed.TypedXMLStreamException

initBinaryChunks

public void initBinaryChunks(org.codehaus.stax2.typed.Base64Variant v,
                    org.codehaus.stax2.ri.typed.CharArrayBase64Decoder dec,
                    boolean firstChunk)

Method that needs to be called to configure given base64 decoder with textual contents collected by this buffer.

Parameters:

dec - Decoder that will need data

firstChunk - Whether this is the first segment fed or not; if it is, state needs to be fullt reset; if not, only partially.

contentsAsString

public String contentsAsString()

contentsAsStringBuilder

public StringBuilder contentsAsStringBuilder(int extraSpace)

Similar to contentsAsString(), but constructs a StringBuilder for further appends.

Parameters:

extraSpace - Number of extra characters to preserve in StringBuilder beyond space immediately needed to hold the contents

contentsToStringBuilder

public void contentsToStringBuilder(StringBuilder sb)

contentsAsArray

public char[] contentsAsArray()

contentsToArray

public int contentsToArray(int srcStart,
                  char[] dst,
                  int dstStart,
                  int len)

rawContentsTo

public int rawContentsTo(Writer w)
                  throws IOException

Method that will stream contents of this buffer into specified Writer.

Throws:

IOException

rawContentsViaReader

public Reader rawContentsViaReader()
                            throws IOException

Throws:

IOException

isAllWhitespace

public boolean isAllWhitespace()

endsWith

public boolean endsWith(String str)

Method that can be used to check if the contents of the buffer end in specified String.

Returns:

True if the textual content buffer contains ends with the specified String; false otherwise

equalsString

public boolean equalsString(String str)

Note: it is assumed that this method is not used often enough to be a bottleneck, or for long segments. Based on this, it is optimized for common simple cases where there is only one single character segment to use; fallback for other cases is to create such segment.

fireSaxCharacterEvents

public void fireSaxCharacterEvents(ContentHandler h)
                            throws SAXException

Throws:

SAXException

fireSaxSpaceEvents

public void fireSaxSpaceEvents(ContentHandler h)
                        throws SAXException

Throws:

SAXException

fireSaxCommentEvent

public void fireSaxCommentEvent(LexicalHandler h)
                         throws SAXException

Throws:

SAXException

fireDtdCommentEvent

public void fireDtdCommentEvent(DTDEventListener l)

validateText

public void validateText(org.codehaus.stax2.validation.XMLValidator vld,
                boolean lastSegment)
                  throws XMLStreamException

Throws:

XMLStreamException

ensureNotShared

public void ensureNotShared()

Method called to make sure that buffer is not using shared input buffer; if it is, it will copy such contents to private buffer.

append

public void append(char c)

append

public void append(char[] c,
          int start,
          int len)

append

public void append(String str)

getCurrentSegment

public char[] getCurrentSegment()

getCurrentSegmentSize

public int getCurrentSegmentSize()

setCurrentLength

public void setCurrentLength(int len)

finishCurrentSegment

public char[] finishCurrentSegment()

toString

public String toString()

Note: calling this method may not be as efficient as calling contentsAsString(), since it's not guaranteed that resulting String is cached.

Overrides:

toString in class Object

unshare

public void unshare(int needExtra)

Method called if/when we need to append content when we have been initialized to use shared buffer.