How to get param value from java servlet -

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I am trying to pass the absolute values ​​for the Java Servlet, but the returned string is not correct. Consolidating the values ​​and checking whether the key exists or not. 

  Map Params; Parameters = request.getParameterMap (); String id = params.get ("id"). ToString (); String data = params.get ("data"). ToString (); System.out.println (+ ID with "Streaming" + Data + "ID);   
 However, if I use  http: // localhost: 8080 / Serv / stream / data = hereisdata and ID = if you call this servicelet through  my output looks like this:  
  streaming [ljava.lang.String; @ [Ljava.lang.String; @ 36314ab8]   
 What am I missing?  
 Edit: The suggested answers are not working I am covering the whole class because I have some fort in class I am growing:   java.util. * Import javax.servlet.http.HttpServletRequest; import engine streamer; public class analyzer controller {private map params; personal string pathInfo; private HttpServletRequest Request; Public Analyst Controller (HTTPSArlet Request) {this.params = request.getParameterMap (); this.pathInfo = request.getPathInfo ();} Public processing with zero process () {system.out.println ("" procing + pathInfo); Switch (pathinfo) {case "/ section / data": if (Paramazo canteens ("id") and parachines canteensky ("data")) process flow (); break; }} Private Zero Process Stream () {System.out.println ("Uses to Stream"); String data = request.getParameter ("data"); String id = request.getParameter ("id"); Stream stream = new streamer (); Stream.streamInput (Data, "Analyzer", ID); }}   
 This line is specifically throwing NPE:  string data = request.getParameter ("data");    
 
 
 If you see the documents, then this  map  Type  map & lt; String returns string [] & gt; . Therefore, you have returned from the map with the value  string []  array.  
  String ID = params.get ("id") must remove the element first. [0];   
 Of course, you can avoid all this and using the method, you can get the parameters directly from the request object.  
  string id = request.getParameter ("id");   
  Edit:  By looking at your class code, it looks like the example variable  request  has not been initiated by the manufacturer Get started in:  
  Public Analyst Controller (HTTPSERT request) {this.request = request; // Start your instance variable request that is used in other methods. This.params = request.getParameterMap (); This.pathInfo = request.getPathInfo (); }

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