通用的泛型服务端响应对象

可放在 src \ main \ java \ com \ 二级包名 \ common 目录下

静态信息 —— ResponseCode.java

• 响应的code值和对应的信息， 可自己修改、添加、删除

public enum ResponseCode {

    SUCCESS(0, "SUCCESS"),
    UNKNOW_ERROR(1, "未知错误"),
    NO_HANDLER_FOUND(1, "找不到执行的路径操作"),
    BIND_EXCEPTION_ERROR(1,"请求参数错误");

    private final int code;
    private final String desc;

    ResponseCode(int code, String desc){
        this.code = code;
        this.desc = desc;
    }

    public int getCode(){
        return code;
    }

    public String getDesc(){
        return desc;
    }
}

方法 —— ServerResponse.java

1. 添加依赖

   <dependency>
       <groupId>org.codehaus.jackson</groupId>
       <artifactId>jackson-mapper-asl</artifactId>
       <version>1.9.12</version>
   </dependency>

2. 响应的结果

   import org.codehaus.jackson.annotate.JsonIgnore;
   import org.codehaus.jackson.map.annotate.JsonSerialize;
   import java.io.Serializable;
   
   @JsonSerialize(include =  JsonSerialize.Inclusion.NON_NULL)
   //保证序列化json的时候,如果是null的对象,key也会消失
   public class ServerResponse<T> implements Serializable {
   
       private int code;
       private String msg;
       private T data;
   
       private ServerResponse(int code){
           this.code = code;
       }
       private ServerResponse(int code,T data){
           this.code = code;
           this.data = data;
       }
   
       private ServerResponse(int code,String msg,T data){
           this.code = code;
           this.msg = msg;
           this.data = data;
       }
   
       private ServerResponse(int code,String msg){
           this.code = code;
           this.msg = msg;
       }
   
       @JsonIgnore
       //使之不在json序列化结果当中
       public boolean isSuccess(){
           return this.code == ResponseCode.SUCCESS.getCode();
       }
   
       public int getCode(){
           return code;
       }
       public T getData(){
           return data;
       }
       public String getMsg(){
           return msg;
       }
   
       public static <T> ServerResponse<T> createBySuccess(){
           return new ServerResponse<T>(ResponseCode.SUCCESS.getCode());
       }
   
       public static <T> ServerResponse<T> createBySuccessMessage(String msg){
           return new ServerResponse<T>(ResponseCode.SUCCESS.getCode(),msg);
       }
   
       public static <T> ServerResponse<T> createBySuccess(T data){
           return new ServerResponse<T>(ResponseCode.SUCCESS.getCode(),data);
       }
   
       public static <T> ServerResponse<T> createBySuccess(String msg,T data){
           return new ServerResponse<T>(ResponseCode.SUCCESS.getCode(),msg,data);
       }
   
       public static <T> ServerResponse<T> createByErrorCodeMessage(int errorCode,String errorMessage){
           return new ServerResponse<T>(errorCode,errorMessage);
       }
   
       public static <T> ServerResponse<T> createByGlobalError(ResponseCode responseCode){
           return new ServerResponse<T>(responseCode.getCode(), responseCode.getDesc());
       }
   }

全局错误处理 —— GlobalExceptionHandler

1. 添加依赖

   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-aop</artifactId>
   </dependency>

2. 全局处理

   import org.springframework.web.bind.ServletRequestBindingException;
   import org.springframework.web.bind.annotation.ControllerAdvice;
   import org.springframework.web.bind.annotation.ExceptionHandler;
   import org.springframework.web.bind.annotation.ResponseBody;
   import org.springframework.web.servlet.NoHandlerFoundException;
   
   import javax.servlet.http.HttpServletRequest;
   import javax.servlet.http.HttpServletResponse;
   
   @ControllerAdvice
   public class GlobalExceptionHandler {
   
       @ExceptionHandler(Exception.class)
       @ResponseBody
       public ServerResponse doError(HttpServletRequest servletRequest, HttpServletResponse httpServletResponse, Exception ex){
           if (ex instanceof  Exception) {
               // throw 的错误
               return ServerResponse.createByErrorCodeMessage(1, ex.getMessage());
           } else if (ex instanceof NoHandlerFoundException) {
               // url 不匹配
               return ServerResponse.createByGlobalError(ResponseCode.NO_HANDLER_FOUND);
           } else if (ex instanceof ServletRequestBindingException) {
               // 参数字段不匹配
               return ServerResponse.createByGlobalError(ResponseCode.BIND_EXCEPTION_ERROR);
           } else {
               // 其他错误
               return ServerResponse.createByGlobalError(ResponseCode.UNKNOW_ERROR);
           }
       }
   }

3. 向 application.properties 添加配置

   # 不匹配 url 时，不适用静态文件返回，则可返回上面的错误 json
   spring.resources.add-mappings=false
   spring.mvc.throw-exception-if-no-handler-found=true

使用例子

1. 只传status

   ServerResponse.createBySuccess()
   ServerResponse.createByError()
   ServerResponse.createByErrorCodeMessage(自定义code, "") // 这个会带个空字符串

   返回

   {
   	status: 
   }

2. 传 status 和 msg

   ServerResponse.createBySuccessMessage("信息")
   ServerResponse.createByErrorCodeMessage("信息")
   ServerResponse.createByErrorCodeMessage(自定义code, "信息")

   返回

   {
   	status: ,
   	msg:
   }

3. 传 status 和 data

   ServerResponse.createBySuccess(数据)

   返回

   {
   	status: ,
   	data:
   }

4. 传 status 和 msg 和 data

   ServerResponse.createBySuccess("信息", 数据)

   返回

   {
   	status: ,
   	mag: ,
   	data:
   }