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Use checkstyle to force a parameter to be present on any method with specific annotation

I want that all my rest services has as an input parameter HttpServletRequest httpRequest that I need later for some loggin purposes. This parameter sometimes is forgotten to be added and some methods are not logged. As are all rest services, and I am using Spring, all of them has some very specific annotations. I was thinking on using checkstyles to force the parameter to be present.
A little more of explanation of want I want to achieve. I am developing some rest servicies, and I am interested on logging some header that are sent to the rest services with some extra information. For this purpose, I have added HttpServletRequest request to each rest services as follows:
#GetMapping(value = "/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
#ResponseStatus(HttpStatus.OK)
public Status get(HttpServletRequest request, #PathVariable("id") Integer id) {
....
}
This paremeter is correctly retrieved and I can read the headers correctly (everything automated using AspectJ). My problem now is that is for a new rest service, I forgot to add the parameter, no logs will be shown. As the parameter is optional (you can or cannot add to the rest service without any error) and all logging is automated by AspectJ, is possible that I can forget it for future rest services and no notice the miss until late.
The scope is to ensure that always is present in all my rest services. My first thought was using checkstyle as I am already using for other different purposes.
Is it possible using checkstyle or any similar tool to force that a parameter is present on any method that has an annotation? If not, there is any other different way to achive my objective?

AspectJ with Spring : intercepted methods lose their parameters annotations

I recently added AOP with aspectJ and spring-aop to my existent spring project. The goal was to actually intercept controller calls to modify the response they send back, in order to bind some values to this response I didn't want to add manually to each and everyone of my controllers, for example the expiration date of the actual token used by the end-user (which I wasn't even able to showcase within my controller in any case). I actually managed to get it working until I started my unit tests :
In my unit tests I call directly my controller methods using Reflection feature from java, then replicate usual process (calling the filter chain, pre handler and post handlers, and the controller method itself which is first manually validated using spring validator when annotation #Valid is present on one of my parameters. All this process works fine and gets executed properly). The problem is that now that the controller method is intercepted by spring-aop, it's mentionned as coming from the proxy controller created, and all of my parameters annotations disapear. Here is a controller example :
#Override
public ResponseEntity<Object> editPassword(#Valid #RequestBody PasswordEditForm passwordEditForm, HttpServletRequest request) {
return factorizedUserBaseController.editPassword(passwordEditForm, request, User.class);
}
the parameter PasswordEditForm has the annotation #Valid so in my test cases it was first validated before any other step, but now as I double checked it, the #Valid annotation is not present on the proxy method, and therefore the parameter doesn't get validated, any clue for how to fix this and make my parameters annotation still understandable from my test point of view?
Note : when running the spring through mvn spring-boot:run, parameters with #Valid annotation gets correctly validated and then goes to my error handler method properly.

Problem Solved : from several other stackoverflow posts I understand that CGLIB (aop proxy lib used by Spring) doesn't support annotations. ( see Retain annotations on CGLIB proxies?). But my problem wasn't here, I was literally sure I was finding the method using the controller class itself (the one I coded) but what I was wrong about is that I was giving the controller instance as a parameter to some other parts of my code which in turn would use this controller class to find the method which of course wasn't working because thanks to Spring proxies, it wasn't anymore my controller itself but a proxy class extending my own controller class. Instead, I just had to replace :
Class<?> controllerClass = controllerInstanciationContainer
.getController()
.getClass();
with
Class<?> controllerClass = controllerInstanciationContainer
.getController()
.getClass()
.getSuperclass();

Any simple way to test a #RequestBody method?

If I have a #Controller method whose parameter is a #RequestBody param, I usually have to write some jQuery script or something similar to perform an AJAX request with JSON object in order to call that method. If I tried calling that method via a web browser directly, it returns with a Error 415 Unsupported Media Type.
Is there any alternative to just quickly call such method using browser without having to write some jQuery code? Like perhaps a way to write the JSON object in the URL/address bar?
code:
#RequestMapping("testCall")
#ResponseBody
public List<TestObject> getTestCall (#RequestBody TestParams testParams) {
return stuff;
}
public class TestParams {
private Integer testNumber;
//getter/setter for testNumber
}
I thought maybe I could just do:
http://localhost/testCall?testNumber=1
maybe Spring would auto populate a new TestParams instance with that property set to 1 but that didnt work...
maybe I need to do something extra for that?

The whole point of a #RequestBody annotated parameters is for the Spring MVC stack to use the HTTP request body to produce an argument that will be bound to the parameter. As such, you need to provide a request body. Sending a request body is very atypical for a GET request. As such, browsers don't typically support it, at least not when simply entering an address in the address bar and submitting the request.
You'll need to use a different HTTP client, like jQuery. I typically have a small Java project in Eclipse that's setup with an Apache HTTP components client which can send HTTP requests to whatever server. It takes a few seconds/minutes to setup the correct request body and run.

I have spent the last year building a REST API, and by far the best way to exercise that API manually is using the Chrome Extension, Postman. I cannot recommend this tool enough.
https://chrome.google.com/webstore/detail/postman-rest-client/fdmmgilgnpjigdojojpjoooidkmcomcm?hl=en
To test your simple example you'll need to invoke a POST (I assume that as you have a request body, but your controller method doesn't define a HTTP Verb) using POSTMAN to your Url (like the following example):
POST /contextRoot/testCall
{
"testNumber": 1
}
If you want to test your API automatically (which I recommend), you can use the excellent Spring Mvc Test project. This allows your to call your API via a rest-like DSL and assert that the response is in the shape you want. More details can be found here:
http://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/testing.html#spring-mvc-test-framework

you can add request params to the getTestCall method:
#RequestParam(value = "testNumber", required = false, defaultValue = "") String testNumber

There is a chrome app called Advanced REST client. You can pass the data in form of json to your controller using this chrome app. For eg. json data is
id:1,
name:"xyz"
whereas the controller can have #RequestBody Person form.
The Person class would be a POJO having id and name as instance variables. The Spring would automatically map the json data to the form.
I think this is the easiest and simplest way of checking your spring controller.
Check the extension Advanced REST client here

From what I know You can send JSON object to the webbrowser and it will be displayed without further need of AJAX.
useful tutorial:
http://www.mkyong.com/spring-mvc/spring-3-mvc-and-json-example/

use HttpServletRequest in my Spring MVC application? Any benefits?

I came across authentication code in my company's java code. The application is a set of several REST services built on Spring MVC. There is a method that gets called in one of the authentication services on the HttpServletRequest object called getHeader(). And the method retrieves an AuthId. Why would they use HttpServletRequest in a spring MVC application? What are the benefits of using this servlet type code in the spring app? What would this method do? Any alternatives?

Spring MVC provides a lot of fabulous abstractions on top of HttpServletRequest, so you can avoid its low-level implementation details. You rarely need to access it directly.
For example, you could get a header value like Content-Type like this:
#GET
#Path("/myService")
public Response doSomething(#HeaderParam("Content-Type") String contentType) {
...
}
But there are times when you do need to access the HttpServletRequest directly--usually when you are using another API that demands it. If you are using some other library with a method you need that takes HttpServletRequest, then you got to grab it from Spring MVC directly.
For example, check out this method in this random UrlUtil class:
public static String encodeUrlPathSegment(String pathSegment, HttpServletRequest httpServletRequest) {
//Get a path segment
}
You have no choice but to grab HttpServletRequest from Spring MVC.

Spring MVC is built on the Servlet API. Anything you could do with a Servlet, you can therefore do with Spring MVC. What the Spring MVC framework provides is a wrapper to code a web application in a specific architectural style. This wrapper adds behavior and some times simplifies tasks.
Why would they use HttpServletRequest in a spring MVC application?
In this case, because it is the most direct way to get the header.
What are the benefits of using this servlet type code in the spring
app?
Spring doesn't have to wrap anything. You get it directly from the source.
What would this method do?
Read the javadoc.
Any alternatives?
In a #Controller class' handler method, you can declare a parameter annotated with #RequestHeader and have Spring pass an argument that it retrieves from the HttpServletRequest headers.
This is, by default, restricted to #Controller methods annotated with #RequestMapping. If your service class is a HandlerInterceptor, Filter, or other type of class and simply has a reference to the HttpServletRequest object, there is nothing more you can do than retrieve it directly with getHeader(String).

Here is an alternative : Spring MVC define the parameter annotation #RequestHeader to read httpServletRequest headers :
#RequestMapping(...)
public #ResponseBody String myMethod(#RequestHeader String AuthId){
//the value of the parameter AuthId is the value of request header named AuthId
...
}

Spring - Abstracting url mapping to handle common url parameters

Assume the following setup:
We have multiple commands mapped to different URLs, each of these with its own body, which we can capture using mappings, like:
#RequestMapping(value = "url1/{param}/command", method = RequestMethod.POST)
#ResponseBody
public Response command1(#PathVariable("param") String param,
#RequestParam(value = urlParam) Param urlParam,
#RequestBody Request request) {
...}
We have several cases where the same parameter repeats in several urls, specifically the URL parameter. Since we have several such variables, today we manually add them to each mapping which is error prone and too verbose.
Is there anyway of routing all mappings through an initial mapping, capturing all those url parameters, and thus remove the clutter from all other mappings?

If you switch from Spring MVC to any JAX-RS framework (e.g. Jersey, Apache Wink), you can use subresources:
#Path("/parent/{id}")
class ParentResource {
#Path("/child1")
Child1Resource getChild() {
....
}
#Path("/child2")
Child2Resource getChild() {
....
}
}
Pay attention that methods with #Path annotations are not annotated with HTTP Methods, so any relevant HTTP request matching the url will propagate into the subresources.
Another suggestion to reduce the error-proning: use constants (public final static String) as parameters both when you create the url and when you use the parameter. This makes it a little bit more verbose, but reduce the error-proning. It can be used both with Spring-MVC and JAX-RS. Don't forget that it's possible to put constants inside the annotation values.
Hope this helps.