net.sf.json.util
Class JSONTokener

java.lang.Object
  extended by net.sf.json.util.JSONTokener

public class JSONTokener
extends Object

A JSONTokener takes a source string and extracts characters and tokens from it. It is used by the JSONObject and JSONArray constructors to parse JSON source strings.

Version:
4
Author:
JSON.org

Constructor Summary
JSONTokener(String s)
          Construct a JSONTokener from a string.
 
Method Summary
 void back()
          Back up one character.
static int dehexchar(char c)
          Get the hex value of a character (base16).
 int length()
           
 boolean matches(String pattern)
           
 boolean more()
          Determine if the source string still contains characters that next() can consume.
 char next()
          Get the next character in the source string.
 char next(char c)
          Consume the next character, and check that it matches a specified character.
 String next(int n)
          Get the next n characters.
 char nextClean()
          Get the next char in the string, skipping whitespace and comments (slashslash, slashstar, and hash).
 String nextString(char quote)
          Return the characters up to the next close quote character.
 String nextTo(char d)
          Get the text up but not including the specified character or the end of line, whichever comes first.
 String nextTo(String delimiters)
          Get the text up but not including one of the specified delimeter characters or the end of line, whichever comes first.
 Object nextValue()
          Get the next value.
 Object nextValue(JsonConfig jsonConfig)
          Get the next value.
 char peek()
          Look at the next character in the source string.
 void reset()
           
 void skipPast(String to)
          Skip characters until past the requested string.
 char skipTo(char to)
          Skip characters until the next character is the requested character.
 JSONException syntaxError(String message)
          Make a JSONException to signal a syntax error.
 String toString()
          Make a printable string of this JSONTokener.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

JSONTokener

public JSONTokener(String s)
Construct a JSONTokener from a string.

Parameters:
s - A source string.
Method Detail

dehexchar

public static int dehexchar(char c)
Get the hex value of a character (base16).

Parameters:
c - A character between '0' and '9' or between 'A' and 'F' or between 'a' and 'f'.
Returns:
An int between 0 and 15, or -1 if c was not a hex digit.

back

public void back()
Back up one character. This provides a sort of lookahead capability, so that you can test for a digit or letter before attempting to parse the next number or identifier.


length

public int length()

matches

public boolean matches(String pattern)

more

public boolean more()
Determine if the source string still contains characters that next() can consume.

Returns:
true if not yet at the end of the source.

next

public char next()
Get the next character in the source string.

Returns:
The next character, or 0 if past the end of the source string.

next

public char next(char c)
Consume the next character, and check that it matches a specified character.

Parameters:
c - The character to match.
Returns:
The character.
Throws:
JSONException - if the character does not match.

next

public String next(int n)
Get the next n characters.

Parameters:
n - The number of characters to take.
Returns:
A string of n characters.
Throws:
JSONException - Substring bounds error if there are not n characters remaining in the source string.

nextClean

public char nextClean()
Get the next char in the string, skipping whitespace and comments (slashslash, slashstar, and hash).

Returns:
A character, or 0 if there are no more characters.
Throws:
JSONException

nextString

public String nextString(char quote)
Return the characters up to the next close quote character. Backslash processing is done. The formal JSON format does not allow strings in single quotes, but an implementation is allowed to accept them.

Parameters:
quote - The quoting character, either " (double quote) or ' (single quote).
Returns:
A String.
Throws:
JSONException - Unterminated string.

nextTo

public String nextTo(char d)
Get the text up but not including the specified character or the end of line, whichever comes first.

Parameters:
d - A delimiter character.
Returns:
A string.

nextTo

public String nextTo(String delimiters)
Get the text up but not including one of the specified delimeter characters or the end of line, whichever comes first.

Parameters:
delimiters - A set of delimiter characters.
Returns:
A string, trimmed.

nextValue

public Object nextValue()
Get the next value. The value can be a Boolean, Double, Integer, JSONArray, JSONObject, Long, or String, or the JSONObject.NULL object.

Returns:
An object.
Throws:
JSONException - If syntax error.

nextValue

public Object nextValue(JsonConfig jsonConfig)
Get the next value. The value can be a Boolean, Double, Integer, JSONArray, JSONObject, Long, or String, or the JSONObject.NULL object.

Returns:
An object.
Throws:
JSONException - If syntax error.

peek

public char peek()
Look at the next character in the source string.

Returns:
The next character, or 0 if past the end of the source string.

reset

public void reset()

skipPast

public void skipPast(String to)
Skip characters until past the requested string. If it is not found, we are left at the end of the source.

Parameters:
to - A string to skip past.

skipTo

public char skipTo(char to)
Skip characters until the next character is the requested character. If the requested character is not found, no characters are skipped.

Parameters:
to - A character to skip to.
Returns:
The requested character, or zero if the requested character is not found.

syntaxError

public JSONException syntaxError(String message)
Make a JSONException to signal a syntax error.

Parameters:
message - The error message.
Returns:
A JSONException object, suitable for throwing

toString

public String toString()
Make a printable string of this JSONTokener.

Overrides:
toString in class Object
Returns:
" at character [this.myIndex] of [this.mySource]"