title: Create JSON data NVD3 Chart using Java
body: <p>I working on NVD3 chart where need to create JSON data for chart as below:</p>
  
  <pre><code>[{ 
    "key" : "North America" , 
    "values" : [ [ 1025409600000 , 23.041422681023] , [ 1028088000000 , 19.854291255832] ]
  },
  
  { 
    "key" : "Africa" , 
    "values" : [ [ 1025409600000 , 23.041422681023] , [ 1028088000000 , 19.854291255832] ]
  },
  
  { 
    "key" : "South America" , 
    "values" : [ [ 1025409600000 , 23.041422681023] , [ 1028088000000 , 19.854291255832] ]
  }]
  </code></pre>
  
  <p>Would somebody please help me create above JSON data using Java as I am trying to create this structure since last 3 hours not successful yet.</p>
  
  <p>Here is the Plunker link: <a href="http://plnkr.co/edit/CIGW0o?p=preview" rel="nofollow">Stacked Area Chart NVD3</a></p>
  
  <p>Here is the live JSON data example which I want to create in JAVA: <a href="http://nvd3.org/examples/stackedAreaData.json" rel="nofollow">JSON example data</a></p>