script.groovy

GroovyScriptEngine engine = new GroovyScriptEngine(".");
Map<String, String> request = new HashMap();
request.put("param1", "Hello");
Map<String, String> response = new HashMap();
response.put("param1", "World");
Binding binding = new Binding();
binding.setVariable("request", request);
binding.setVariable("response", response);
engine.run("src/main/java/"+className, binding);

import com.jayway.jsonpath.JsonPath;
import com.jayway.jsonpath.Configuration;


String json = "{\"user\":\"deepak\"}";
Object document = Configuration.defaultConfiguration().jsonProvider().parse(json);

println JsonPath.read(document, "\$.user");


def makethiswork(request, response){
    return request.param1 + ' ' + response.param1;
}


response.param1 = makethiswork(request, response)