Spring3 Controller: ModelAndView vs String - Which is Better?

When developing a web application using Spring3, one of the common questions that arise is whether to use a ModelAndView or a String as the return type for a controller method. Both options have their pros and cons, and the choice ultimately depends on the specific requirements of your application.

ModelAndView is a class provided by Spring that allows you to combine a model object with a view name, providing a more structured way to return data and views from a controller method. With ModelAndView, you can add attributes to the model object and specify the view name to be rendered, all in a single return statement. This can make your code more concise and easier to read.

On the other hand, returning a String from a controller method means that you are explicitly specifying the name of the view to be rendered. This can be useful if you have a simple use case where you only need to return a view name and don't need to add any attributes to the model object. It can also be useful when you want to return a redirect or a forward to another controller method or URL.

In terms of performance, using a String is generally faster as it requires less overhead than creating a ModelAndView object. However, the difference in performance is usually negligible unless you are dealing with a large number of requests.

In summary, if you have a complex use case that requires you to add attributes to the model object and specify the view name in a single return statement, ModelAndView is the way to go. If you have a simple use case where you only need to return a view name, or if you want to return a redirect or a forward, using a String is a good option. Ultimately, the choice depends on the specific requirements of your application and your personal preference as a developer.