JSON Java Script Object Notation Copyright © 2013 Curt Hill

What is it? Language for data interchange –Derived from JavaScript (ECMA standard) –Alternative to XML in that respect Both easy for people to read and easy for machines to parse Consists of sequences and attribute- value pairs It is an open standard Copyright © 2013 Curt Hill

Simple Types Does not have many Number –A floating point type String –Enclosed in double quotes –Uses UNICODE characters Boolean –May be true or false null –Indicates an empty value Copyright © 2013 Curt Hill

Structured Types Only two structuring types Object –Similar to a group, record, or struct, depending on language –Unordered, comma separated list of name value pairs enclosed in braces –The key is separated from the value by a colon Array –An ordered, comma separated list of values enclosed in brackets Copyright © 2013 Curt Hill

Commentary White space may be interspersed for readability without changing meaning Hardly any programming language lacks these features –Most have a JSON interface Keys are merely strings Copyright © 2013 Curt Hill

Example A simple object to contain a name: { “first”:”Bill”, “lastname”: “Smith” } An array of names inside an object: { “employees” : [ {“first”:”Bill”, “last”:“Sam” }, {“first”:”John”, “last”:“Doe” }, {“first”:”Curt”, “last”:“Hill” } ] } Copyright © 2013 Curt Hill

Example 2 An array of objects that describe a products: {“products [ { “name”: “Widget”, “price”:24.91}, { “name”: “Gizmo”, “price”:2.28}, { “name”: “Junk”, “price”:6} ] } Copyright © 2013 Curt Hill

BSON Binary JSON also exists This is a binary encoded serialization of JSON objects These should be more compact and faster to parse Copyright © 2013 Curt Hill