List<Team_event> data = teamService.selEvent();

JsonResult<String> j1 = new JsonResult(data); //直接把data放到裡面了

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.41</version>
</dependency>

{
"success":true,
"message":null,
"errorCode":"0",
"errorMsg":"操作成功",
"total":0,
"data":[
{
"eventcontent":"街邊攤販佔道經營，影響行人交通，造成擁堵。",
"problem":"街邊攤販佔道經營，影響行人交通，造成擁堵。"
}
]
}

package com.example.Entity;

import com.alibaba.fastjson.annotation.JSONField;
import lombok.Data;

import java.util.ArrayList;
 
import java.util.List;

/**
 * 通用JsonResult
 */
@Data
public class JsonResult<T> {
    private static final long serialVersionUID =-123847128341023033L;
    @JSONField
    private boolean success = true;
    @JSONField
    private String message = null;
    @JSONField
    private String errorCode = "0";
    @JSONField
    
 
private String errorMsg = "";
    @JSONField
    private Integer total = 0;
    @JSONField
    private List<T> data = new ArrayList();

    public JsonResult() {
    }

    /**
     * 當有異常時，直接throw一個實現ErrorCode的異常類
     * 通過global異常處理器，就可以把jsonResult封裝起來，這樣程式碼簡潔優美
     * 如果沒有BaseException可以註釋掉這個方法
     */
//    public JsonResult(BaseException exception) {
//        if (exception != null) {
//            success = false;
//            errorCode = exception.getErrorCode();
//            errorMsg = exception.getErrorMsg();
//        }
//    }
    /**
     *  雖然很多人都寫為isSuccess(),但強烈不建議，因為相當於getSuccess()
     *  可以用idea的自動生成下，如果有isSuccess()，就不會生成getSuccess()
     */
    public boolean successFlag() {
        return success;
    }

    public JsonResult(List<T> data) {
        if (data != null && data.size() > 0) {
            this.data = data;
            this.message = "操作成功";
        }else {
            this.message = "操作失敗";
            this.errorCode = "405";
            this.errorMsg = "返回值為null";
        }
    }

    public JsonResult(T data) {
        if (data != null) {
            this.data.add(data);
            this.message = "操作成功";
        }else {
            this.message = "操作失敗";
            this.errorCode = "405";
            this.errorMsg = "返回值為null";
        }
    }
    //  失敗情況的構造  只用errorCode，errorMsg即可
    public JsonResult(String errorCode,String errorMsg) {
        this.success=false;
        this.errorCode=errorCode;
        this.errorMsg=errorMsg;
    }
}