使用Spring 4.2，我如何将路径变量作为可选项

Question

@RequestMapping(value="/return/{name}",method=RequestMethod.GET)
public ResponseEntity<String> ReturnName(HttpServletRequest req,@PathVariable(name) String inputName) {
    return new ResponseEntity<>(inputName, HttpStatus.OK)
}

I have found the solution like

@RequestMapping(value="/return/{name}",method=RequestMethod.GET)
public ResponseEntity<String> ReturnName(HttpServletRequest req,@PathVariable(name) Optional<String> inputName) {
    return new ResponseEntity<>(inputName.isPresent() ? inputName.get() : null, HttpStatus.OK)
}

But it is not working as expected.

It throws 405 if the value for name is not give.

Example :

return/ram is working fine.

return throws 405 error.

Whether i am missing anything?

Is there any spring property to handle this?

Thanks in advance.

Answer 1

您不能，只需创建另一种方法来捕获URL中没有{name}的URL。

@RequestMapping(value="/return",method=RequestMethod.GET)

Answer 2

To make your own proposed solution work and use a single method, you can use like this:

@RequestMapping(value= {"/return/{name}", "/return"},method=RequestMethod.GET)
public ResponseEntity<String> ReturnName(HttpServletRequest req, @PathVariable("name") Optional<String> inputName) {
    return new ResponseEntity<>(inputName.isPresent() ? inputName.get() : null, HttpStatus.OK);
}

In the end it is still 2 endpoints like Baldurian proposed.

Answer 3

Try this:

@RequestMapping(value= {"/return/{name}", "/return"},method=RequestMethod.GET)
public ResponseEntity<String> ReturnName(HttpServletRequest req, @PathVariable("name") Optional<String> inputName) {
    return new ResponseEntity<>(inputName.isPresent() ? inputName.get() : null, HttpStatus.OK);
}