Two Java projects, when cross-domain access, the browser does not correctly resolve data problems

@Controller
@RequestMapping (value = "API")
public class Apiitemcatcontroller {

@Autowired
Private Itemcatservice Itemcatservice;

@RequestMapping (method = Requestmethod.get)
Public responseentity<string> Queryitemcatall (@RequestParam (value= "callback", required =false) String callback ) {
try {
Invoking service queries
Itemcatresult result = Itemcatservice.queryitemcatall ();
Objectmapper mapper = new Objectmapper ();
String Jsonresult = mapper.writevalueasstring (result);
To determine whether a cross-domain request
if (Stringutils.isnotempty (callback)) {
Return Responseentity.ok (callback + "(" +jsonresult+ ")");
}
If not, return the result and success status code directly
Return results and Status codes
Return Responseentity.status (Httpstatus.ok). Body (Jsonresult);
} catch (Exception e) {
E.printstacktrace ();
}
Return Responseentity.status (Httpstatus.internal_server_error). Body (
NULL);

}
}

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The Url:http://manage.taotao.com/rest/api/item/cat?callback=category.getdataservice of another system

Two Java projects, when cross-domain access, the browser does not correctly resolve data problems