jsdsi.sexp
Class Sexp

java.lang.Object
  jsdsi.sexp.Sexp

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

SexpList, SexpString

public abstract class Sexp

extends java.lang.Object

implements java.io.Serializable

Abstract S-expression superclass. Provides static utility functions. S-expressions are immutable.

Version:

$Revision: 1.2.2.1 $ $Date: 2005/11/08 03:12:52 $

Author:

Sameer Ajmani

See Also:

SexpString, SexpList, Serialized Form

Field Summary

static char[]	base64Digit Maps integers to base-64 digits.
static char[]	hexDigit Maps integers to hexadecimal digits.

Constructor Summary

Sexp()

Method Summary

static java.lang.String	decodeString(byte[] b) Converts a byte array to a string using the 8859_1 encoding.
static byte[]	encodeString(java.lang.String s) Converts a string to a byte array using the 8859_1 encoding.
static java.lang.String	getEncoding() Returns the character encoding for S-expressions (8859_1).
int	getReadableLen() Returns the length of this S-expression as if it were printed on one line.
static boolean	isBase64Digit(int c) Tests if a character is a base 64 digit.
static boolean	isDecimalDigit(int c) Tests if a character is a decimal digit.
static boolean	isHexDigit(int c) Tests if a character is a hexadecimal digit.
static boolean	isTokenChar(int c) Tests if a character is a token character.
static boolean	isWhiteSpace(int c) Tests if a character is whitespace.
abstract void	writeCanonical(java.io.OutputStream out) Writes this S-expression to a byte stream in canonical form.
abstract void	writeReadable(java.io.Writer out, int offset, int width, int last) Writes this S-expression to a character stream in readable form.
void	writeTransport(java.io.OutputStream out) Writes this S-expression to a byte stream in transport form.

Methods inherited from class java.lang.Object

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

Field Detail

hexDigit

public static final char[] hexDigit

Maps integers to hexadecimal digits.

base64Digit

public static final char[] base64Digit

Maps integers to base-64 digits.

Constructor Detail

Sexp

public Sexp()

Method Detail

getEncoding

public static final java.lang.String getEncoding()

Returns the character encoding for S-expressions (8859_1).

Returns:

"8859_1"

isWhiteSpace

public static final boolean isWhiteSpace(int c)

Tests if a character is whitespace.

Parameters:

c - the character to be tested

Returns:

true if the character is whitespace, false otherwise

isDecimalDigit

public static final boolean isDecimalDigit(int c)

Tests if a character is a decimal digit.

Parameters:

c - the character to be tested

Returns:

true if the character is a digit between 0 and 9 inclusive, false otherwise

isHexDigit

public static final boolean isHexDigit(int c)

Tests if a character is a hexadecimal digit.

Parameters:

c - the character to be tested.

Returns:

true if the character is a decimal digit or a letter between 'a' and 'f' upper or lowercase, false otherwise .

isBase64Digit

public static final boolean isBase64Digit(int c)

Tests if a character is a base 64 digit.

Parameters:

c - the character to be tested.

Returns:

true if the character is a decimal digit, a letter of the alphabet or '+' or '/', false otherwise.

isTokenChar

public static final boolean isTokenChar(int c)

Tests if a character is a token character.

Parameters:

c - the character to be tested.

Returns:

true if the character is a legal token character for an S-expression, false otherwise.

decodeString

public static java.lang.String decodeString(byte[] b)

Converts a byte array to a string using the 8859_1 encoding.

encodeString

public static byte[] encodeString(java.lang.String s)

Converts a string to a byte array using the 8859_1 encoding.

writeCanonical

public abstract void writeCanonical(java.io.OutputStream out)
                             throws java.io.IOException

Writes this S-expression to a byte stream in canonical form.

Throws:

java.io.IOException

writeTransport

public final void writeTransport(java.io.OutputStream out)
                          throws java.io.IOException

Writes this S-expression to a byte stream in transport form.

Throws:

java.io.IOException

writeReadable

public abstract void writeReadable(java.io.Writer out,
                                   int offset,
                                   int width,
                                   int last)
                            throws java.io.IOException

Writes this S-expression to a character stream in readable form.

Parameters:

offset - spaces indented from left.

width - total width of window, in characters.

last - spaces reserved on right (e.g., for closing parens).

Throws:

java.io.IOException

getReadableLen

public final int getReadableLen()

Returns the length of this S-expression as if it were printed on one line. Caches result for efficiency.

See Also:

#getReadableLenImpl()