Perform Ajax Call from JSP pages to controller or servlet in request.getParameter and return a JSON object from controller.

JSP_ajax_to_controller.jsp

 $scope.sendmessage= function(from,to,msg,status){
	
			 $.ajax({
			        type: 'POST',
			        url: '<%=request.getContextPath()%>/MainController',
			        data: {
			        	"from" : from,
			           	"to" : to,
		      		 	"message" : msg,
		      		 	"action": "sendmsg",
		      		 	"status" :status
			        },
			        dataType: 'json',
			        success: function(data) {
			           
			            console.log(data);
		
			            $scope.message=data.message;
			        	
			        	alert($scope.message);     
                //KEY VALUE PAIR -> used to form grid of incoming data dynamically.
               $scope.keys=Object.keys($scope.message);			   


                $scope.$apply();
			        },
			        error: function(jqXHR, textStatus, errorThrown){
			        	
			        	 $scope.message="Internal Server Error. Please try again later.";
			        	 $scope.$apply();
			        	 
			   
			            
			        }       
			    }); 
			 
			 
		 };