Java JSON Tutorial - JSON Data Types

The following table lists the data types supported by JSON.

Type	Description
Number	double-precision, floating-point format in JavaScript. Octal and hexadecimal formats are not used. No NaN or Infinity. Example, 1,9, 0,-4. Fractions like .3, .9 Exponent like e, e+, e-,E, E+, E- var json-object-name = { string : number_value}
String	double-quoted Unicode with backslash escaping. Escape sequence: \b \f \n \r \t \u var json-object-name = { string : "string value"}
Boolean	true or false var json-object-name = { name: true/false,}
Array	An ordered sequence of values. Array elements are enclosed square brackets [element,element,element, ].
Value	Can be a string, a number, true or false, null etc
Object	An unordered collection of key:value pairs. Object are enclosed in curly braces starts with '{' and ends with '}'. key:value pairs are separated by , The keys must be strings and should be different from each other. { string : value, string1 : value1,.......}
Whitespace	can be used between any pair of tokens
null	empty

Example

Example showing Number Datatype, value should not be quoted:

var obj = {grade: 97}

Example of String data type.

var obj = {name: 'abc'}

var obj = {name: 'Jack', 
           grade: 97, 
           pass: true}

The following JSON data has an array of three books.

{
  "books": [
   { "language":"Java" , "edition":"second" },
   { "language":"C++" , "edition":"fifth" },
   { "language":"C" , "edition":"third" }
  ]
}

Example showing Object:

{
 "id": "1",
 "language": "Java",
 "page": 500,
}