如何从Play中的Action引发错误或异常？

Question

I read the official document of PlayFramework about Error handling. And I learned it is good to use HttpErrorHandler class. And they say such error handling classes can catch errors or exceptions from Action . And I saw methods of DefaultHttpErrorHandler class. However, how does the DefaultHttpErrorHandler class distinguish errors or exceptions thrown from Action ? Some method such as onServerError takes int argument as its parameter, so in this case how does Action throw errors or exceptions? Does other page show it?

Answer 1

Basically, an exception thrown in a Controller will result of a 500 http error code. The onServerError method will catch and handle this exception.

On the other side, 400, 401, 403 or 404 http error codes are called "Client error" in Play environnement. These errors are catch and handle by the onClientError method.

Thus, if you want to have a dedicated and customized page for 404 http error page ("Page not found"), build the given view and call it inside the onClientError method (you have the statusCode parameter to distinct 404 from 400, 401 or other http status code).

If you want to have a custom error page, you have to call the dedicated view in onServerError method.