net.sf.saxon.tinytree
Class LargeStringBuffer

java.lang.Object
  net.sf.saxon.tinytree.LargeStringBuffer

All Implemented Interfaces:

java.lang.CharSequence, java.io.Serializable

public final class LargeStringBuffer

extends java.lang.Object

implements java.lang.CharSequence, java.io.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). When characters are appended, a new segment is started if the previous array would otherwise overflow a threshold size (the maxAllocation size).

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, the value of each text node is contiguous within one segment, so extraction of the value of a text node is efficient.

See Also:

Serialized Form

Constructor Summary

LargeStringBuffer()
Create an empty LargeStringBuffer with default space allocation

LargeStringBuffer(int minAllocation, int maxAllocation)
Create an empty LargeStringBuffer

Method Summary

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

LargeStringBuffer

public LargeStringBuffer(int minAllocation,
                         int maxAllocation)

Create an empty LargeStringBuffer

Parameters:

minAllocation - initial allocation size for each segment (including the first)

maxAllocation - maximum allocation size for each segment. When a segment reaches this size, a new segment is created rather than appending more characters to the existing segment.

Method Detail

append

public void append(java.lang.CharSequence data)

Append a CharSequence to this LargeStringBuffer

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 java.lang.CharSequence

Returns:

the number of characters in this sequence

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 java.lang.CharSequence

Parameters:

index - the index of the character to be returned

Returns:

the specified character

Throws:

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

subSequence

public java.lang.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 java.lang.CharSequence

Parameters:

start - the start index, inclusive

end - the end index, exclusive

Returns:

the specified subsequence

Throws:

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

toString

public java.lang.String toString()

Convert to a string

Specified by:

toString in interface java.lang.CharSequence

equals

public boolean equals(java.lang.Object other)

Compare equality

hashCode

public int hashCode()

Generate a hash code

substring

public java.lang.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.

write

public void write(java.io.Writer writer)
           throws java.io.IOException

Write the value to a writer

Throws:

java.io.IOException