Spring MVC @RequestParam - 多个关键名称？ 或另一种要求“一个或另一个”的方式

Question

What is the best way to allow multiple names for query parameters? I have a web service which has changed parameter names, but must continue for a while to accept the old names.

I'm loath to create 2 RequestParams, both not required, b/c I do require one or the other to be present. Something like this would be sweet:

@RequestParam(value = "startTime|start", required = true ) String startTime,

rather than

@RequestParam(value = "startTime", required = false ) String startTime,
@RequestParam(value = "start", required = false ) String start ){
if ( start != null || startTime != null ){ //  ... 

Is there any way to do this? Thanks.

Answer 1

You can do something like this (create a proxy method that will intercept the "old" calls and transfer them to the new method):

@RequestMapping(value="/your-mapping", params = {"oldparam1", "oldparam2", ...})
public Whatever yourOldMethod(@RequestParam(value="oldparam1", required=true) String oldParam1, ...){
   return yourNewMethod(oldParam1, ...);
}

@RequestMapping(value="/your-mapping", params = {"newparam1", "newparam1", ...})
public Whatever yourNewMethod(@RequestParam(value="newparam1", required=true) String oldParam1, ...){
   //do whatever you need to do here
}

When you don't need to support the old calls, simply delete yourOldMethod .

The beauty here, is using the "params" of @RequestMapping , thus allowing 2 methods to listen to the same "URL" (with different params for each)