public class WebApiExceptionTest extends UnitFessTestCase {

    public void test_constructor_withStatusCodeAndMessage() {
        // Test constructor with status code and message
        int statusCode = 404;
        String message = "Resource not found";

        WebApiException exception = new WebApiException(statusCode, message);

        assertEquals(statusCode, exception.getStatusCode());

The status codes in the 400 range mean that there was an error from the client.

Remember all those **"404 Not Found"** errors (and jokes)?

## Use `HTTPException` { #use-httpexception }

To return HTTP responses with errors to the client you use `HTTPException`.

### Import `HTTPException` { #import-httpexception }

**FastAPI** will take that model, generate its JSON Schema and include it in the correct place in OpenAPI.

For example, to declare another response with a status code `404` and a Pydantic model `Message`, you can write:

{* ../../docs_src/additional_responses/tutorial001.py hl[18,22] *}

/// note

Keep in mind that you have to return the `JSONResponse` directly.

///

/// info

        }

        try (final ResponseData responseData = smbClient.doGet(baseUrl + "none")) {
            assertEquals(0, responseData.getStatus());
            assertEquals(404, responseData.getHttpStatusCode());
            assertEquals(0, responseData.getContentLength());
            assertNull(responseData.getResponseBody());
            assertEquals(baseUrl + "none", responseData.getUrl());

///

## Response Status Code { #response-status-code }

You can define the (HTTP) `status_code` to be used in the response of your *path operation*.

You can pass directly the `int` code, like `404`.

But if you don't remember what each number code is for, you can use the shortcut constants in `status`:

{* ../../docs_src/path_operation_configuration/tutorial001_py310.py hl[1,15] *}

* **`400 - 499`** are for "Client error" responses. These are the second type you would probably use the most.
    * An example is `404`, for a "Not Found" response.
    * For generic errors from the client, you can just use `400`.

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

Then if you go to the URLs at `/openapi.json`, `/docs`, or `/redoc` you will just get a `404 Not Found` error like:

```JSON
{
    "detail": "Not Found"
}

			// whether you also have the s3:ListBucket
			// permission.
			// * If you have the s3:ListBucket permission
			//   on the bucket, Amazon S3 will return an
			//   HTTP status code 404 ("no such key")
			//   error.
			// * if you don’t have the s3:ListBucket
			//   permission, Amazon S3 will return an HTTP
			//   status code 403 ("access denied") error.`

        responseData1.setHttpStatusCode(200);
        assertTrue(rule.match(responseData1));

        ResponseData responseData2 = new ResponseData();
        responseData2.setHttpStatusCode(404);
        assertFalse(rule.match(responseData2));

        ResponseData responseData3 = new ResponseData();
        responseData3.setHttpStatusCode(500);
        assertFalse(rule.match(responseData3));
    }

        StatusCodeWebApiManager manager = new StatusCodeWebApiManager(404);

        TestHttpServletRequest request = new TestHttpServletRequest();
        TestHttpServletResponse response = new TestHttpServletResponse();
        TestFilterChain chain = new TestFilterChain();

        manager.process(request, response, chain);
        assertEquals(404, response.getStatus());

        // Test with different status code