com.api.json

Class JSONStreamTokenizer

java.lang.Object

com.api.json.JSONStreamTokenizer

public class JSONStreamTokenizer
extends Object

This class provides similar services to StreamTokenizer but it works on a character by character basis, whereas the StreamTokenizer is based on individual bytes so is not handling solidus nor unicode correctly. This class is solely for parsing JSON content.

Field Summary

Fields

Modifier and Type	Field and Description
double	nval
String	sval
static int	TT_CR
static int	TT_EOF
static int	TT_EOL
static int	TT_NUMBER
static int	TT_WORD
int	ttype

Constructor Summary

Constructors

Constructor and Description
JSONStreamTokenizer(Reader r) Constructs the JST from a Reader.

Method Summary

Modifier and Type	Method and Description
void	eolIsSignificant(boolean flag) Sets reporting when end of line is detected
int	nextToken(Integer[] location) Discovers the next token in the reader and returns its type (ttype).
void	ordinaryChar(int ch) Sets the supplied character as ordinary in the character lookup table
void	ordinaryChars(int low, int hi) Sets the range of characters supplied (including the endpoints) as ordinary in the character lookup table
void	parseNumbers() Initializes the character lookup table for known digits for numeric characters, along with the decimal point and minus sign.
void	pushBack() Flags that a character has been returned after completing reading the next token.
void	quoteChar(int ch) Sets the supplied character as a quote delimiter for quoted word identification in the character lookup table
void	resetSyntax() Resets the character lookup table with single byte characters as ordinary, and double byte characters as parts of words.
String	toString() Convenience method to see the state of the next token and its type (e.g., while debugging)
void	whitespaceChars(int low, int hi) Sets the range of characters as whitespace in the character lookup table
void	wordChars(int low, int hi) Flags the supplied range of characters as word characters in the lookup table.

Methods inherited from class java.lang.Object

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

Field Detail

TT_EOF

public static final int TT_EOF

See Also:

Constant Field Values

TT_CR

public static final int TT_CR

See Also:

Constant Field Values

TT_EOL

public static final int TT_EOL

See Also:

Constant Field Values

TT_NUMBER

public static final int TT_NUMBER

See Also:

Constant Field Values

TT_WORD

public static final int TT_WORD

See Also:

Constant Field Values

nval

public double nval

sval

public String sval

ttype

public int ttype

Constructor Detail

JSONStreamTokenizer

public JSONStreamTokenizer(Reader r)

Constructs the JST from a Reader. There is no constructor for an InputStream because it can be made into a reader. The same is true for a String.

Parameters:

r - the reader to be read containing JSON content.

Method Detail

eolIsSignificant

public void eolIsSignificant(boolean flag)

Sets reporting when end of line is detected

Parameters:

flag - whether or not to report when end of line is detected

nextToken

public int nextToken(Integer[] location)
              throws IOException

Discovers the next token in the reader and returns its type (ttype). If a number is detected, it is returned as a double in the nval. If a word or quoted word is detected, it is returned in the sval.

Parameters:

location - where we are reading from the input stream

Returns:

the type of next token encountered in the reader

Throws:

IOException - if unable to read from the reader

ordinaryChar

public void ordinaryChar(int ch)

Sets the supplied character as ordinary in the character lookup table

Parameters:

ch - The character to be tested

ordinaryChars

public void ordinaryChars(int low,
                          int hi)

Sets the range of characters supplied (including the endpoints) as ordinary in the character lookup table

Parameters:

low - starting, lower value character

hi - ending, higher value character

parseNumbers

public void parseNumbers()

Initializes the character lookup table for known digits for numeric characters, along with the decimal point and minus sign. TODO: add plus sign?

pushBack

public void pushBack()
              throws IOException

Flags that a character has been returned after completing reading the next token.

Throws:

IOException - if unable to read from the reader

quoteChar

public void quoteChar(int ch)

Sets the supplied character as a quote delimiter for quoted word identification in the character lookup table

Parameters:

ch - The character defining a quote character

resetSyntax

public void resetSyntax()

Resets the character lookup table with single byte characters as ordinary, and double byte characters as parts of words.

toString

public String toString()

Convenience method to see the state of the next token and its type (e.g., while debugging)

Overrides:

toString in class Object

See Also:

Object.toString()

whitespaceChars

public void whitespaceChars(int low,
                            int hi)

Sets the range of characters as whitespace in the character lookup table

Parameters:

low - starting, lower range of whitespace characters

hi - ending, higher range of whitespace characters

wordChars

public void wordChars(int low,
                      int hi)

Flags the supplied range of characters as word characters in the lookup table. These characters may also be flagged as numeric characters

Parameters:

low - starting, lower character range of word characters

hi - ending, higher character range of word characters