[springmvc] Views vs. @ResponseBody

1. Two different systems exist for rendering responses

　　ViewResolver + View

　　HttpMessageConverter

2. Triggered in different ways

　　Render a view by returning a String

　　Write a message by returning a @ResponseBody Object or ResponseEntity

3. Which one do I use?

　　Use views to generate documents for display in a web browser: HTML, PDF, etc

　　Use @ResponseBody to exchange data with web service clients: JSON, XML, etc