响应数据

定义

@ResponseBody注解可将方法返回值直接响应给浏览器
如果返回值类型是 实体对象/集合 ，将会转换为JSON格式响应
@ResponseBody作用在Controller方法上/类上，因此也叫方法注解/类注解

@RestController = @Controller + @ResponseBody

统一响应

实体对象

//实体对象
public class Result {
    //响应码，1 代表成功; 0 代表失败
    private Integer code;
    //提示信息
    private String msg;
    //返回的数据
    private Object data;

    public Result() {
    }
    public Result(Integer code, String msg, Object data) {
        this.code = code;
        this.msg = msg;
        this.data = data;
    }
    public Integer getCode() {
        return code;
    }
    public void setCode(Integer code) {
        this.code = code;
    }
    public String getMsg() {
        return msg;
    }
    public void setMsg(String msg) {
        this.msg = msg;
    }
    public Object getData() {
        return data;
    }
    public void setData(Object data) {
        this.data = data;
    }
    //查询 成功响应(把查询结果做为返回数据响应给前端)
    public static Result success(Object data){
        return new Result(1, "success", data);
    }
    //增删改 成功响应(不需要给前端返回数据)
    public static Result success(){
        return new Result(1, "success", null);
    }
    //失败响应
    public static Result error(String msg){
        return new Result(0, msg, null);
    }
}

controller方法

@RestController
public class ResponseController {
//controller方法1
@RequestMapping("/hello")
    public Result hello(){
    System.out.println("Hello World ~");
    //return new Result(1,"success","Hello World ~");
    return Result.success("Hello World ~");
}
//controller方法2
@RequestMapping("/getAddr")
    public Result getUser(){
    Address addr = new Address();//实体对象
    addr.setProvince("广东");
    addr.setCity("深圳");
    return Result.success(addr);
}
//controller方法3
@RequestMapping("/listAddr")
public Result listAddr(){
    List<Address> list = new ArrayList<>();//集合数据
    Address addr = new Address();
    addr.setProvince("广东");
    addr.setCity("深圳");
    Address addr2 = new Address();
    addr2.setProvince("陕西");
    addr2.setCity("西安");
    list.add(addr);
    list.add(addr2);
    return Result.success(list);
}
}

响应数据

//响应数据1
{
    "code": 1,
    "msg": "success",
    "data": "Hello World ~"
}
//响应数据2
{
    "code": 1,
    "msg": "success",
    "data": {
        "province": "广东",
        "city": "深圳"
     }
}
//响应数据3
{
    "code": 1,
    "msg": "success",
    "data": [
        {
        "province": "广东",
        "city": "深圳"
        }
        {
        "province": "陕西",
        "city": "西安"
        }
    ]
}