Retrieve the data sent as JSON from JavaScript, inside a servlet

Question

I have a query on retrieving data sent as JSON from a JavaScript, inside a Java servlet. Following is what I am doing... This is the part of the code inside JavaScript making a request to a servlet ``` type : "POST", url: 'getInitialData', datatype: 'json', data : ({items :[{ name: "John", time: "2pm" },{name: "Sam", time: "1pm" }]}), success: function(data) { try{ ////Code to be handeled where response is recieved }catch(e){ alert(e); } } ``` On making this request I try to retrieve the parameters sent from JavaScript in a Servlet, but while doing so I was firstly confused on how to retrieve the dat from the request I used the following in my servlet: NOTE : the content Type in my Servlet is set to : apllication/json ``` response.setContentType("application/json"); request.getParameterMap(); ``` the above showed me the data as below, but I was not able figure out how to work and get the actual data ``` {items[1][name]=[Ljava.lang.String;@1930089, items[0][time]=[Ljava.lang.String;@86…

Accepted Answer

The request parameter map is a `Map<String, String[]>` where the map key is the parameter name and map value are the parameter values --HTTP allows more than one value on the same name.

Given the printout of your map, the following should work:

```
String item0Name = request.getParameter("items[0][name]");
String item0Time = request.getParameter("items[0][time]");
String item1Name = request.getParameter("items[1][name]");
String item1Time = request.getParameter("items[1][time]");
```

If you want a bit more dynamics, use the following:

```
for (int i = 0; i < Integer.MAX_VALUE; i++) {
    String itemName = request.getParameter("items[" + i + "][name]");
    String itemTime = request.getParameter("items[" + i + "][time]");

if (itemName == null) {
        break;
    }

// Collect name and time in some bean and add to list yourself.
}
```

Note that setting the response content type is irrelevant when it comes to gathering the request parameters.

Retrieve the data sent as JSON from JavaScript, inside a servlet

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