net.sf.saxon.tinytree

Class CharSlice

Implemented Interfaces:
CharSequence, Serializable

public final class CharSlice
extends java.lang.Object
implements CharSequence, Serializable

This is an implementation of the JDK 1.4 CharSequence interface: it implements a CharSequence as a view of an array. The implementation relies on the array being immutable: as a minimum, the caller is required to ensure that the array contents will not change so long as the CharSlice remains in existence. This class should be more efficient than String because it avoids copying the characters unnecessarily. The methods in the class don't check their arguments. Incorrect arguments will generally result in exceptions from lower-level classes.

Constructor Summary

CharSlice(char[] array)
Create a CharSlice that maps to the whole of a char[] array
CharSlice(char[] array, int start, int length)
Create a CharSlice that maps to a section of a char[] array

Method Summary

char
charAt(int index)
Returns the character at the specified index.
void
copyTo(char[] destination, int destOffset)
Append the contents to another array at a given offset.
boolean
equals(Object other)
Compare equality
int
hashCode()
Generate a hash code
int
indexOf(char c)
Get the index of a specific character in the sequence.
int
length()
Returns the length of this character sequence.
void
setLength(int length)
Set the length of this character sequence, without changing the array and start offset to which it is bound
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

Constructor Details

CharSlice

public CharSlice(char[] array)
Create a CharSlice that maps to the whole of a char[] array
Parameters:
array - the char[] array

CharSlice

public CharSlice(char[] array,
                 int start,
                 int length)
Create a CharSlice that maps to a section of a char[] array
Parameters:
array - the char[] array
start - position of the first character to be included
length - number of characters to be included

Method Details

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.
Parameters:
index - the index of the character to be returned
Returns:
the specified character

copyTo

public void copyTo(char[] destination,
                   int destOffset)
Append the contents to another array at a given offset. The caller is responsible for ensuring that sufficient space is available.
Parameters:
destination - the array to which the characters will be copied
destOffset - the offset in the target array where the copy will start

equals

public boolean equals(Object other)
Compare equality

hashCode

public int hashCode()
Generate a hash code

indexOf

public int indexOf(char c)
Get the index of a specific character in the sequence. Returns -1 if not found. This method mimics String.indexOf
Parameters:
c - the character to be found
Returns:
the position of the first occurrence of that character, or -1 if not found.

length

public int length()
Returns the length of this character sequence. The length is the number of 16-bit Unicode characters in the sequence.
Returns:
the number of characters in this sequence

setLength

public void setLength(int length)
Set the length of this character sequence, without changing the array and start offset to which it is bound
Parameters:
length - the new length of the CharSlice (which must be less than the existing length, though this is not enforced)

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.
Parameters:
start - the start index, inclusive
end - the end index, exclusive
Returns:
the specified subsequence

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 - position of the first character to be included (relative to the start of the CharSlice, not the underlying array)
end - position of the first character not to be included (relative to the start of the CharSlice)
Returns:
the substring, as a String object

toString

public String toString()
Convert to a string

write

public void write(Writer writer)
            throws java.io.IOException
Write the value to a writer
Parameters:
writer - the writer to be written to