统一封装json返回结果

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 ServiceResponse<T> implements Serializable {
    private int status;  //结果状态值
    private String msg;  //结果信息
    private T data;      //结果数据

    private ServiceResponse(int status){
        this.status = status;
    }

    private ServiceResponse(int status, T data){
        this.status = status;
        this.data = data;
    }

    private ServiceResponse(int status, String msg, T data){
        this.status = status;
        this.msg = msg;
        this.data = data;
    }

    private ServiceResponse(int status, String msg){
        this.status = status;
        this.msg = msg;
    }

    @JsonIgnore //让其不在json序列化中
    public boolean isSuccess(){
        return this.status == ResponseCode.SUCCESS.getCode();
    }

    public int getStatus() {
        return status;
    }

    public String getMsg() {
        return msg;
    }

    public T getData() {
        return data;
    }

    public static <T> ServiceResponse<T> createBySuccess(){
        return new ServiceResponse<T>(ResponseCode.SUCCESS.getCode());
    }

    public static <T> ServiceResponse<T> createBySuccessMessage(String msg){
        return new ServiceResponse<T>(ResponseCode.SUCCESS.getCode(), msg);
    }

    public static <T> ServiceResponse<T> createBySuccess(T data){
        return new ServiceResponse<T>(ResponseCode.SUCCESS.getCode(), data);
    }

    public static <T> ServiceResponse<T> createBySuccess(String msg, T data){
        return new ServiceResponse<T>(ResponseCode.SUCCESS.getCode(), msg, data);
    }

    public static <T> ServiceResponse<T> createByError(){
        return new ServiceResponse<T>(ResponseCode.ERROR.getCode(), ResponseCode.ERROR.getDesc());
    }

    public static <T> ServiceResponse<T> createByErrorMessage(String errorMessage){
        return new ServiceResponse<T>(ResponseCode.ERROR.getCode(), errorMessage);
    }

    public static <T> ServiceResponse<T> createByErrorCodeMessage(int errorCode, String errorMessage){
        return new ServiceResponse<T>(errorCode, errorMessage);
    }
}

使用到的枚举值

/**
 * 状态枚举值
 */
public enum ResponseCode {

    SUCCESS(0,"SUCCESS"),
    ERROR(1,"ERROR"),
    NEED_LOGIN(10,"NEED_LOGIN"),
    ILLEGAL_ARGUMENT(2,"ILLEGAL_ARGUMENT");

    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;
    }
}