java restful @QueryParam 获 取 JSP 表单的值

java restful @QueryParam获取JSP表单的值，为什么有的可以拿到，有的是null

Java代码 收藏代码
@Path("/users")

public class UserService {

@GET  
@Path("/query")  
public Response getUsers(@Context UriInfo info) {  

    String from = info.getQueryParameters().getFirst("from");  
    String to = info.getQueryParameters().getFirst("to");  
    List<String> orderBy = info.getQueryParameters().get("orderBy");  

    return Response  
       .status(200)  
       .entity("getUsers is called, from : " + from + ", to : " + to  
        + ", orderBy" + orderBy.toString()).build();  

}  

URL;users/query?from=100&to=200&orderBy=age&orderBy=name
输出为:
getUsers is called, from : 100, to : 200, orderBy[age, name]
注意这里把orderby后的两个参数读入为LIST处理了.