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FastJson将json解析成含有泛型对象，内部泛型对象再次解析出错的

发布时间：2020-12-16 18:39:41 所属栏目：百科 来源：网络整理
导读：折腾小半天的问题，这里先感谢一下深圳的小伙子，远程帮我搞，虽然也没有搞出来==========FUCK 声明：Android开发下发生此异常，Java开发下并不会有这个问题 异常重现 简单说一下抛出异常的代码： （1）解析json代码如下： 1 2 RecommendBeanRecommendListBe

折腾小半天的问题，这里先感谢一下深圳的小伙子，远程帮我搞，虽然也没有搞出来==========FUCK

声明：Android开发下发生此异常，Java开发下并不会有这个问题

异常重现

简单说一下抛出异常的代码：

（1）解析json代码如下：

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RecommendBean<RecommendListBean> obj = JSON.parSEObject(jsonString,? new? TypeReference<RecommendBean<RecommendListBean>>(){});
RecommendListBean recommendListBean = (RecommendListBean) (obj.getData());

错误日志如下：

java.lang.ClassCastException: com.alibaba.fastjson.JSONObject cannot be cast to com.test.RecommendListBean

（2）model 如下：

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package? com.test;
?
/**
? * Created by Travis on 2017/8/20.
? */
?
public? class? RecommendBean<T> {
?
???? private? int? status;
???? private? String message;
???? private? T data;
?
???? public? int? getStatus() {
???????? return? status;
???? }
?
???? public? void? setStatus( int? status) {
???????? this .status = status;
???? }
?
???? public? String getMessage() {
???????? return? message;
???? }
?
???? public? void? setMessage(String message) {
???????? this .message = message;
???? }
?
???? public? T getData() {
???????? return? data;
???? }
?
???? public? void? setData(T data) {
???????? this .data = data;
???? }
}

　　

 
package com.test;

import java.util.List;

/**
 * Created by lenovo on 2017/8/20.
 */

public class RecommendListBean {

    private int count;
    private List<RecommendListItemBean> list;

    public int getCount() {
        return count;
    }

    public void setCount(int count) {
        this.count = count;
    }

    public List<RecommendListItemBean> getList() {
        return list;
    }

    public void setList(List<RecommendListItemBean> list) {
        this.list = list;
    }





}

?

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package? com.test;
?
import? java.io.Serializable;
?
/**
? * Created by Travis on 2017/8/20.
? */
?
public? class? RecommendListItemBean? implements? Serializable {
???? private? static? final? long? serialVersionUID = 21455356667888L;
?
???? private? int? uid;
???? private? String nickname;
???? private? int? sex;
???? private? int? age;
???? private? String avatar;
???? private? String theme_pic;
???? private? String job;
???? private? String signature;
???? private? String sound;
???? private? int? sound_length;
???? private? int? fee;
?
???? public? RecommendBean getRecommend() {
???????? return? recommend;
???? }
?
???? public? void? setRecommend(RecommendBean recommend) {
???????? this .recommend = recommend;
???? }
?
???? private? RecommendBean recommend;
?
???? public? int? getUid() {
???????? return? uid;
???? }
?
???? public? void? setUid( int? uid) {
???????? this .uid = uid;
???? }
?
???? public? String getNickname() {
???????? return? nickname;
???? }
?
???? public? void? setNickname(String nickname) {
???????? this .nickname = nickname;
???? }
?
???? public? int? getSex() {
???????? return? sex;
???? }
?
???? public? void? setSex( int? sex) {
???????? this .sex = sex;
???? }
?
???? public? int? getAge() {
???????? return? age;
???? }
?
???? public? void? setAge( int? age) {
???????? this .age = age;
???? }
?
???? public? String getAvatar() {
???????? return? avatar;
???? }
?
???? public? void? setAvatar(String avatar) {
???????? this .avatar = avatar;
???? }
?
???? public? String getTheme_pic() {
???????? return? theme_pic;
???? }
?
???? public? void? setTheme_pic(String theme_pic) {
???????? this .theme_pic = theme_pic;
???? }
?
???? public? String getJob() {
???????? return? job;
???? }
?
???? public? void? setJob(String job) {
???????? this .job = job;
???? }
?
???? public? String getSignature() {
???????? return? signature;
???? }
?
???? public? void? setSignature(String signature) {
???????? this .signature = signature;
???? }
?
?
???? public? static? class? RecommendBean<T>? implements? Serializable {
???????? private? static? final? long? serialVersionUID = 21455356667889L;
?
???????? private? int? id;
???????? private? int? user_id;
???????? private? int? type;
???????? private? Object content;
???????? private? int? zan;
???????? private? int? status;
???????? private? String create_time;
???????? private? String update_time;
???????? private? int? zanTotal;
???????? private? int? commentTotal;
???????? private? T picture;
???????? private? T video;
?
???????? public? int? getType() {
???????????? return? type;
???????? }
?
???????? public? void? setType( int? type) {
???????????? this .type = type;
???????? }
?
???????? public? int? getId() {
???????????? return? id;
???????? }
?
???????? public? void? setId( int? id) {
???????????? this .id = id;
???????? }
?
???????? public? int? getUser_id() {
???????????? return? user_id;
???????? }
?
???????? public? void? setUser_id( int? user_id) {
???????????? this .user_id = user_id;
???????? }
?
???????? public? Object getContent() {
???????????? return? content;
???????? }
?
???????? public? void? setContent(Object content) {
???????????? this .content = content;
???????? }
?
???????? public? int? getZan() {
???????????? return? zan;
???????? }
?
???????? public? void? setZan( int? zan) {
???????????? this .zan = zan;
???????? }
?
???????? public? int? getStatus() {
???????????? return? status;
???????? }
?
???????? public? void? setStatus( int? status) {
???????????? this .status = status;
???????? }
?
???????? public? String getCreate_time() {
???????????? return? create_time;
???????? }
?
???????? public? void? setCreate_time(String create_time) {
???????????? this .create_time = create_time;
???????? }
?
???????? public? String getUpdate_time() {
???????????? return? update_time;
???????? }
?
???????? public? void? setUpdate_time(String update_time) {
???????????? this .update_time = update_time;
???????? }
?
???????? public? int? getZanTotal() {
???????????? return? zanTotal;
???????? }
?
???????? public? void? setZanTotal( int? zanTotal) {
???????????? this .zanTotal = zanTotal;
???????? }
?
???????? public? int? getCommentTotal() {
???????????? return? commentTotal;
???????? }
?
???????? public? void? setCommentTotal( int? commentTotal) {
???????????? this .commentTotal = commentTotal;
???????? }
?
???????? public? T getPicture() {
???????????? return? picture;
???????? }
?
???????? public? void? setPicture(T picture) {
???????????? this .picture = picture;
???????? }
?
???????? public? T getVideo() {
???????????? return? video;
???????? }
?
???????? public? void? setVideo(T video) {
???????????? this .video = video;
???????? }
???? }
}

　　

原因分析：

? ??

?

经过debug发现此处泛型所在的地方，仍然还是JSONObject，而没有解析成对应的对象，仅仅只是将obj解析成需要的实体对象了。

即使此处使用强转，仍然会有报错信息：cannot be cast to com.test.RecommendListBean

解决办法: ??换用GSON来解析，具体方法如下

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Gson gson =? new? Gson();
RecommendBean<RecommendListBean> obj = gson.fromJson(jsonString,? new? TypeToken<RecommendBean<RecommendListBean>>(){}.getType());
RecommendListBean recommendListBean = (RecommendListBean) (obj.getData());

（编辑：李大同）

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