JSONTokener

java.lang.Object
- org.json.JSONTokener

```
public class JSONTokener
extends java.lang.Object
```
Parses a JSON (RFC 4627) encoded string into the corresponding object. Most clients of this class will use only need the constructor and nextValue() method. Example usage:
```
 String json = "{"
         + "  \"query\": \"Pizza\", "
         + "  \"locations\": [ 94043, 90210 ] "
         + "}";

 JSONObject object = (JSONObject) new JSONTokener(json).nextValue();
 String query = object.getString("query");
 JSONArray locations = object.getJSONArray("locations");
```
For best interoperability and performance use JSON that complies with RFC 4627, such as that generated by JSONStringer. For legacy reasons this parser is lenient, so a successful parse does not indicate that the input string was valid JSON. All of the following syntax errors will be ignored:
- End of line comments starting with // or # and ending with a newline character.
- C-style comments starting with /* and ending with */. Such comments may not be nested.
- Strings that are unquoted or 'single quoted'.
- Hexadecimal integers prefixed with 0x or 0X.
- Octal integers prefixed with 0.
- Array elements separated by ;.
- Unnecessary array separators. These are interpreted as if null was the omitted value.
- Key-value pairs separated by = or =>.
- Key-value pairs separated by ;.
Each tokener may be used to parse a single JSON string. Instances of this class are not thread safe. Although this class is nonfinal, it was not designed for inheritance and should not be subclassed. In particular, self-use by overrideable methods is not specified. See Effective Java Item 17, "Design and Document or inheritance or else prohibit it" for further information.

Field Summary

Fields
Modifier and Type Field and Description

private java.lang.String in
The input JSON.

private int pos
The index of the next character to be returned by next().

Fields
Modifier and Type	Field and Description
`private java.lang.String`	`in` The input JSON.
`private int`	`pos` The index of the next character to be returned by `next()`.

Constructor Summary

Constructors
Constructor and Description

JSONTokener(java.lang.String in)

Constructors
Constructor and Description
`JSONTokener(java.lang.String in)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`back()` Unreads the most recent character of input.
`static int`	`dehexchar(char hex)` Returns the integer [0..15] value for the given hex character, or -1 for non-hex input.
`boolean`	`more()` Returns true until the input has been exhausted.
`char`	`next()` Returns the next available character, or the null character '\0' if all input has been exhausted.
`char`	`next(char c)` Returns the next available character if it equals `c`.
`java.lang.String`	`next(int length)` Returns the next `length` characters of the input.
`char`	`nextClean()` Returns the next character that is not whitespace and does not belong to a comment.
`private int`	`nextCleanInternal()`
`java.lang.String`	`nextString(char quote)` Returns the string up to but not including `quote`, unescaping any character escape sequences encountered along the way.
`java.lang.String`	`nextTo(char excluded)` Equivalent to `nextTo(String.valueOf(excluded))`.
`java.lang.String`	`nextTo(java.lang.String excluded)` Returns the `trimmed` string holding the characters up to but not including the first of: any character in `excluded` a newline character '\n' a carriage return '\r'
`private java.lang.String`	`nextToInternal(java.lang.String excluded)` Returns the string up to but not including any of the given characters or a newline character.
`java.lang.Object`	`nextValue()` Returns the next value from the input.
`private JSONArray`	`readArray()` Reads a sequence of values and the trailing closing brace ']' of an array.
`private char`	`readEscapeCharacter()` Unescapes the character identified by the character or characters that immediately follow a backslash.
`private java.lang.Object`	`readLiteral()` Reads a null, boolean, numeric or unquoted string literal value.
`private JSONObject`	`readObject()` Reads a sequence of key/value pairs and the trailing closing brace '}' of an object.
`void`	`skipPast(java.lang.String thru)` Advances past all input up to and including the next occurrence of `thru`.
`char`	`skipTo(char to)` Advances past all input up to but not including the next occurrence of `to`.
`private void`	`skipToEndOfLine()` Advances the position until after the next newline character.
`JSONException`	`syntaxError(java.lang.String message)` Returns an exception containing the given message plus the current position and the entire input string.
`java.lang.String`	`toString()` Returns the current position and the entire input string.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - in
```
private final java.lang.String in
```
    The input JSON.
  - pos
```
private int pos
```
    The index of the next character to be returned by next(). When the input is exhausted, this equals the input's length.
- Constructor Detail
  - JSONTokener
```
public JSONTokener(java.lang.String in)
```
    Parameters:
    
    in - JSON encoded string. Null is not permitted and will yield a tokener that throws NullPointerExceptions when methods are called.
- Method Detail
  - nextValue
```
public java.lang.Object nextValue()
                           throws JSONException
```
    Returns the next value from the input.
    
    Returns:
    
    a JSONObject, JSONArray, String, Boolean, Integer, Long, Double or JSONObject.NULL.
    
    Throws:
    
    JSONException - if the input is malformed.
  - nextCleanInternal
```
private int nextCleanInternal()
                       throws JSONException
```
    Throws:
    
    JSONException
  - skipToEndOfLine
```
private void skipToEndOfLine()
```
    Advances the position until after the next newline character. If the line is terminated by "\r\n", the '\n' must be consumed as whitespace by the caller.
  - nextString
```
public java.lang.String nextString(char quote)
                            throws JSONException
```
    Returns the string up to but not including quote, unescaping any character escape sequences encountered along the way. The opening quote should have already been read. This consumes the closing quote, but does not include it in the returned string.
    
    Parameters:
    
    quote - either ' or ".
    
    Throws:
    
    JSONException
  - readEscapeCharacter
```
private char readEscapeCharacter()
                          throws JSONException
```
    Unescapes the character identified by the character or characters that immediately follow a backslash. The backslash '\' should have already been read. This supports both unicode escapes "u000A" and two-character escapes "\n".
    
    Throws:
    
    JSONException
  - readLiteral
```
private java.lang.Object readLiteral()
                              throws JSONException
```
    Reads a null, boolean, numeric or unquoted string literal value. Numeric values will be returned as an Integer, Long, or Double, in that order of preference.
    
    Throws:
    
    JSONException
  - nextToInternal
```
private java.lang.String nextToInternal(java.lang.String excluded)
```
    Returns the string up to but not including any of the given characters or a newline character. This does not consume the excluded character.
  - readObject
```
private JSONObject readObject()
                       throws JSONException
```
    Reads a sequence of key/value pairs and the trailing closing brace '}' of an object. The opening brace '{' should have already been read.
    
    Throws:
    
    JSONException
  - readArray
```
private JSONArray readArray()
                     throws JSONException
```
    Reads a sequence of values and the trailing closing brace ']' of an array. The opening brace '[' should have already been read. Note that "[]" yields an empty array, but "[,]" returns a two-element array equivalent to "[null,null]".
    
    Throws:
    
    JSONException
  - syntaxError
```
public JSONException syntaxError(java.lang.String message)
```
    Returns an exception containing the given message plus the current position and the entire input string.
  - toString
```
public java.lang.String toString()
```
    Returns the current position and the entire input string.
    
    Overrides:
    
    toString in class java.lang.Object
  - more
```
public boolean more()
```
    Returns true until the input has been exhausted.
  - next
```
public char next()
```
    Returns the next available character, or the null character '\0' if all input has been exhausted. The return value of this method is ambiguous for JSON strings that contain the character '\0'.
  - next
```
public char next(char c)
          throws JSONException
```
    Returns the next available character if it equals c. Otherwise an exception is thrown.
    
    Throws:
    
    JSONException
  - nextClean
```
public char nextClean()
               throws JSONException
```
    Returns the next character that is not whitespace and does not belong to a comment. If the input is exhausted before such a character can be found, the null character '\0' is returned. The return value of this method is ambiguous for JSON strings that contain the character '\0'.
    
    Throws:
    
    JSONException
  - next
```
public java.lang.String next(int length)
                      throws JSONException
```
    Returns the next length characters of the input.
    The returned string shares its backing character array with this tokener's input string. If a reference to the returned string may be held indefinitely, you should use new String(result) to copy it first to avoid memory leaks.
    
    Throws:
    
    JSONException - if the remaining input is not long enough to satisfy this request.
  - nextTo
```
public java.lang.String nextTo(java.lang.String excluded)
```
    Returns the trimmed string holding the characters up to but not including the first of:
    - any character in excluded
    - a newline character '\n'
    - a carriage return '\r'
    The returned string shares its backing character array with this tokener's input string. If a reference to the returned string may be held indefinitely, you should use new String(result) to copy it first to avoid memory leaks.
    Returns:
    
    a possibly-empty string
  - nextTo
```
public java.lang.String nextTo(char excluded)
```
    Equivalent to nextTo(String.valueOf(excluded)).
  - skipPast
```
public void skipPast(java.lang.String thru)
```
    Advances past all input up to and including the next occurrence of thru. If the remaining input doesn't contain thru, the input is exhausted.
  - skipTo
```
public char skipTo(char to)
```
    Advances past all input up to but not including the next occurrence of to. If the remaining input doesn't contain to, the input is unchanged.
  - back
```
public void back()
```
    Unreads the most recent character of input. If no input characters have been read, the input is unchanged.
  - dehexchar
```
public static int dehexchar(char hex)
```
    Returns the integer [0..15] value for the given hex character, or -1 for non-hex input.
    
    Parameters:
    
    hex - a character in the ranges [0-9], [A-F] or [a-f]. Any other character will yield a -1 result.

Class JSONTokener

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

in

pos

Constructor Detail

JSONTokener

Method Detail

nextValue

nextCleanInternal

skipToEndOfLine

nextString

readEscapeCharacter

readLiteral

nextToInternal

readObject

readArray

syntaxError

toString

more

next

next

nextClean

next

nextTo

nextTo

skipPast

skipTo

back

dehexchar