SpringMVC注解@RequestParam(value="xxxx",required=false)，

RequestParam来映射请求参数
required表示是否必须,默认为true
defaultValue请求参数的默认值

@RequestMapping(value = “/testRequestParam”)
public String testRequestParam(@RequestParam(value=“username”)String un,@RequestParam(value = “age”,required = false,defaultValue = “0”) int age){
System.out.println(“testRequestParam,username:”+un+",age,"+age);
return “success”;
}

?username=tom$age=30

testRequestparam,username:tom,age,30