added starting request part for getCode

lib/codegen/java/unirest.dart

@@ -74,6 +74,72 @@ public class Main {
     try {
       String result = '';
       bool hasBody = false;
+      var rec = getValidRequestUri(
+        requestModel.url,
+        requestModel.enabledRequestParams,
+      );
+
+      // uri is already generated based on url and enabled request params
+      Uri? uri = rec.$1;
+
+      if (uri == null) {
+        return "";
+      }
+
+      // this is the common import and will be imported for every generated code snippet
+      result += kTemplateUnirestImports;
+
+      // java file io packages are to be imported only when there is a form with file present
+      if (requestModel.hasBody &&
+          kMethodsWithBody.contains(requestModel.method) &&
+          requestModel.hasFormData &&
+          requestModel.hasFileInFormData) {
+        result += kTemplateFileIoImports;
+      }
+
+      // adding the main method under Main class
+      result += kTemplateStart;
+
+      var url = stripUriParams(uri);
+
+      // contains the HTTP method associated with the request
+      var method = requestModel.method;
+
+      // contains the entire request body as a string if body is present
+      var requestBody = requestModel.requestBody;
+
+      // generating the URL to which the request has to be submitted
+      var templateUrl = jj.Template(kTemplateUrl);
+      result += templateUrl.render({"url": url});
+
+      // creating request body if available
+      var rM = requestModel.copyWith(url: url);
+      var harJson = requestModelToHARJsonRequest(rM, useEnabled: true);
+
+      // if request type is not form data, the request method can include
+      // a body, and the body of the request is not null, in that case
+      // we need to parse the body as it is, and write it to the body
+      if (!requestModel.hasFormData &&
+          kMethodsWithBody.contains(method) &&
+          requestBody != null) {
+        // find out the content length for the request, i.e. request body's size
+        var contentLength = utf8.encode(requestBody).length;
+        if (contentLength > 0) {
+          var templateBodyContent = jj.Template(kTemplateRequestBodyContent);
+          hasBody = true;
+          if (harJson["postData"]?["text"] != null) {
+            result += templateBodyContent.render({
+              "body": kEncoder.convert(harJson["postData"]["text"]).substring(
+                  1, kEncoder.convert(harJson["postData"]["text"]).length - 1)
+            });
+          }
+        }
+      }
+
+      var templateRequestCreation = jj.Template(kTemplateRequestCreation);
+      result +=
+          templateRequestCreation.render({"method": method.name.toLowerCase()});
+
 
       return result;
     } catch (e) {