net.sf.saxon.tree.tiny
Class LargeStringBuffer

java.lang.Object
  net.sf.saxon.tree.tiny.LargeStringBuffer

All Implemented Interfaces:

Serializable, CharSequence, AppendableCharSequence

public final class LargeStringBuffer
extends Object
implements AppendableCharSequence, Serializable

This is an implementation of the JDK 1.4 CharSequence interface: it implements a CharSequence as a list of arrays of characters (the individual arrays are known as segments). The segments have a fixed size of 65536 characters.

This is more efficient than a buffer backed by a contiguous array of characters in cases where the size is likely to grow very large, and where substring operations are rare. As used within the TinyTree, extraction of the string value of a node requires character copying only in the case where the value crosses segment boundaries.

See Also:

Serialized Form

Constructor Summary

LargeStringBuffer()
Create an empty LargeStringBuffer with default space allocation

Method Summary

void	append(CharSequence s) Append a CharSequence to this LargeStringBuffer
char	charAt(int index) Returns the character at the specified index.
boolean	equals(Object other) Compare equality
int	hashCode() Generate a hash code
int	length() Returns the length of this character sequence.
void	setLength(int length) Set the length.
CharSequence	subSequence(int start, int end) Returns a new character sequence that is a subsequence of this sequence.
String	substring(int start, int end) Returns a new character sequence that is a subsequence of this sequence.
String	toString() Convert to a string
void	write(Writer writer) Write the value to a writer

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

LargeStringBuffer

public LargeStringBuffer()

Create an empty LargeStringBuffer with default space allocation

Method Detail

append

public void append(CharSequence s)

Append a CharSequence to this LargeStringBuffer

Specified by:

append in interface AppendableCharSequence

Parameters:

s - the data to be appended

length

public int length()

Returns the length of this character sequence. The length is the number of 16-bit UTF-16 characters in the sequence.

Specified by:

length in interface CharSequence

Returns:

the number of characters in this sequence

setLength

public void setLength(int length)

Set the length. If this exceeds the current length, this method is a no-op. If this is less than the current length, characters beyond the specified point are deleted.

Specified by:

setLength in interface AppendableCharSequence

Parameters:

length - the new length

charAt

public char charAt(int index)

Returns the character at the specified index. An index ranges from zero to length() - 1. The first character of the sequence is at index zero, the next at index one, and so on, as for array indexing.

Specified by:

charAt in interface CharSequence

Parameters:

index - the index of the character to be returned

Returns:

the specified character

Throws:

IndexOutOfBoundsException - if the index argument is negative or not less than length()

subSequence

public CharSequence subSequence(int start,
                                int end)

Returns a new character sequence that is a subsequence of this sequence. The subsequence starts with the character at the specified index and ends with the character at index end - 1. The length of the returned sequence is end - start, so if start == end then an empty sequence is returned.

Specified by:

subSequence in interface CharSequence

Parameters:

start - the start index, inclusive

end - the end index, exclusive

Returns:

the specified subsequence

Throws:

IndexOutOfBoundsException - if start or end are negative, if end is greater than length(), or if start is greater than end

toString

public String toString()

Convert to a string

Specified by:

toString in interface CharSequence

Overrides:

toString in class Object

equals

public boolean equals(Object other)

Compare equality

Overrides:

equals in class Object

hashCode

public int hashCode()

Generate a hash code

Overrides:

hashCode in class Object

substring

public String substring(int start,
                        int end)

Returns a new character sequence that is a subsequence of this sequence. Unlike subSequence, this is guaranteed to return a String.

Parameters:

start - index of the first character to be included

end - index of the character after the last one to be included

Returns:

the substring at the given position

write

public void write(Writer writer)
           throws IOException

Write the value to a writer

Parameters:

writer - the writer to which the value is to be written

Throws:

IOException - if an error occurs downstream