For the example below, the first item in the values array (1) can be selected using a JsonPath value of $.data.values.[0]:

{
  "type" : "line", 
  "data" : 
  { 
    "labels" : ["Sunday", "Monday"], 
    "values" : [ 1, 2 ] 
  } 
}

In this example a single numeric value was selected. However it is possible to select a complete subset of the incoming JSON, for example: $.data would select the entire data object into the out slot, or $.data.values would select the entire JSON “values” array. Any expression containing a search with $..labels, for example, will return search results enclosed within an outer array.

Much more explanation of this powerful tool can be found at the following websites: