Java 对象的动态 Json 文件

如何解决Java 对象的动态 Json 文件

我有一个 java 类模型,它有 getter/setter 方法和枚举类型。 我想与所有字段一起公开 JSON 文件,默认情况下,一个字段有值,其他字段为空。

如何使用java模型类创建动态文件。

package com.manifest;

import java.util.HashMap;
import java.util.Map;
import javax.annotation.Generated;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;
import com.fasterxml.jackson.annotation.JsonValue;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
   "@id","@type","dct:identifier"
})
@Generated("jsonschema2pojo")
public class DctMediaType {

/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@id")
private String id;
/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@type")
private DctMediaType.Type type;
@JsonProperty("dct:identifier")
private String dctIdentifier;
@JsonIgnore
private Map<String,Object> additionalProperties = new HashMap<String,Object>();

/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@id")
public String getId() {
    return id;
}

/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@id")
public void setId(String id) {
    this.id = id;
}

public DctMediaType withId(String id) {
    this.id = id;
    return this;
}

/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@type")
public DctMediaType.Type getType() {
    return type;
}

/**
 * 
 * (Required)
 * 
 */
@JsonProperty("@type")
public void setType(DctMediaType.Type type) {
    this.type = type;
}

public DctMediaType withType(DctMediaType.Type type) {
    this.type = type;
    return this;
}

@JsonProperty("dct:identifier")
public String getDctIdentifier() {
    return dctIdentifier;
}

@JsonProperty("dct:identifier")
public void setDctIdentifier(String dctIdentifier) {
    this.dctIdentifier = dctIdentifier;
}

public DctMediaType withDctIdentifier(String dctIdentifier) {
    this.dctIdentifier = dctIdentifier;
    return this;
}

@JsonAnyGetter
public Map<String,Object> getAdditionalProperties() {
    return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name,Object value) {
    this.additionalProperties.put(name,value);
}

public DctMediaType withAdditionalProperty(String name,value);
    return this;
}

@Override
public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append(DctMediaType.class.getName()).append('@').append(Integer.toHexString(System.identityHashCode(this))).append('[');
    sb.append("id");
    sb.append('=');
    sb.append(((this.id == null)?"<null>":this.id));
    sb.append(',');
    sb.append("type");
    sb.append('=');
    sb.append(((this.type == null)?"<null>":this.type));
    sb.append(',');
    sb.append("dctIdentifier");
    sb.append('=');
    sb.append(((this.dctIdentifier == null)?"<null>":this.dctIdentifier));
    sb.append(',');
    sb.append("additionalProperties");
    sb.append('=');
    sb.append(((this.additionalProperties == null)?"<null>":this.additionalProperties));
    sb.append(',');
    if (sb.charAt((sb.length()- 1)) == ',') {
        sb.setCharAt((sb.length()- 1),']');
    } else {
        sb.append(']');
    }
    return sb.toString();
}

@Override
public int hashCode() {
    int result = 1;
    result = ((result* 31)+((this.id == null)? 0 :this.id.hashCode()));
    result = ((result* 31)+((this.dctIdentifier == null)? 0 :this.dctIdentifier.hashCode()));
    result = ((result* 31)+((this.additionalProperties == null)? 0 :this.additionalProperties.hashCode()));
    result = ((result* 31)+((this.type == null)? 0 :this.type.hashCode()));
    return result;
}

@Override
public boolean equals(Object other) {
    if (other == this) {
        return true;
    }
    if ((other instanceof DctMediaType) == false) {
        return false;
    }
    DctMediaType rhs = ((DctMediaType) other);
    return (((((this.id == rhs.id)||((this.id!= null)&&this.id.equals(rhs.id)))&&((this.dctIdentifier == rhs.dctIdentifier)||((this.dctIdentifier!= null)&&this.dctIdentifier.equals(rhs.dctIdentifier))))&&((this.additionalProperties == rhs.additionalProperties)||((this.additionalProperties!= null)&&this.additionalProperties.equals(rhs.additionalProperties))))&&((this.type == rhs.type)||((this.type!= null)&&this.type.equals(rhs.type))));
}

@Generated("jsonschema2pojo")
public enum Type {

    DCT_MEDIA_TYPE("dct:MediaType");
    private final String value;
    private final static Map<String,DctMediaType.Type> CONSTANTS = new HashMap<String,DctMediaType.Type>();

    static {
        for (DctMediaType.Type c: values()) {
            CONSTANTS.put(c.value,c);
        }
    }

    Type(String value) {
        this.value = value;
    }

    @Override
    public String toString() {
        return this.value;
    }

    @JsonValue
    public String value() {
        return this.value;
    }

    @JsonCreator
    public static DctMediaType.Type fromValue(String value) {
        DctMediaType.Type constant = CONSTANTS.get(value);
        if (constant == null) {
            throw new IllegalArgumentException(value);
        } else {
            return constant;
        }
    }

}

}

需要我的 JSON 输出文件,如下所示:

{
 "@id":null,"@type":"dct:MediaType"
 "dct:identifier":null
}

我尝试了以下方法,但得到了空的 json 对象 {}。

ObjectMapper dynamicMapper = new ObjectMapper();
 dynamicMapper.enable(SerializationFeature.INDENT_OUTPUT);
 dynamicMapper.setSerializationInclusion(Include.ALWAYS);
 String jsonValue = dynamicMapper.writeValueAsString(new DctMediaType());

请提出一些创建动态 json 文件的指导。

解决方法

问题是你们都有 @JsonInclude(JsonInclude.Include.NON_NULL) 注释,它告诉序列化程序跳过任何 NULL 值并从 JSON 输出中删除属性,并且您永远不会将字段初始化为任何非空值你的豆子。

您将 new DctMediaType() 传递给映射器,但从未设置任何字段。

听起来如果您想要 JSON 中的空值,那么您应该将注释更改为 @JsonInclude(JsonInclude.Include.ALWAYS)

,

通过使用下面的代码,我可以为我的用例实现解决方案。

Class<?> clazzObj = Class.forName("com.manifest.DctMediaType");
                JsonObject tempObj = new JsonObject();
                for (Field newField : clazzObj.getDeclaredFields()) {
                    if (newField.isAnnotationPresent(JsonProperty.class)) {
                        String annotationValue = newField.getAnnotation(JsonProperty.class).value();
                        String childTypeString = newField.getGenericType().toString();                          
                            tempObj.add(annotationValue,"");

                        }
                      }

我的输出:

 {
    "@id": "","@type": "dct:MediaType","dct:identifier": ""
}

版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。

相关推荐


使用本地python环境可以成功执行 import pandas as pd import matplotlib.pyplot as plt # 设置字体 plt.rcParams[&#39;font.sans-serif&#39;] = [&#39;SimHei&#39;] # 能正确显示负号 p
错误1:Request method ‘DELETE‘ not supported 错误还原:controller层有一个接口,访问该接口时报错:Request method ‘DELETE‘ not supported 错误原因:没有接收到前端传入的参数,修改为如下 参考 错误2:cannot r
错误1:启动docker镜像时报错:Error response from daemon: driver failed programming external connectivity on endpoint quirky_allen 解决方法:重启docker -&gt; systemctl r
错误1:private field ‘xxx‘ is never assigned 按Altʾnter快捷键,选择第2项 参考:https://blog.csdn.net/shi_hong_fei_hei/article/details/88814070 错误2:启动时报错,不能找到主启动类 #
报错如下,通过源不能下载,最后警告pip需升级版本 Requirement already satisfied: pip in c:\users\ychen\appdata\local\programs\python\python310\lib\site-packages (22.0.4) Coll
错误1:maven打包报错 错误还原:使用maven打包项目时报错如下 [ERROR] Failed to execute goal org.apache.maven.plugins:maven-resources-plugin:3.2.0:resources (default-resources)
错误1:服务调用时报错 服务消费者模块assess通过openFeign调用服务提供者模块hires 如下为服务提供者模块hires的控制层接口 @RestController @RequestMapping(&quot;/hires&quot;) public class FeignControl
错误1:运行项目后报如下错误 解决方案 报错2:Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project sb 解决方案:在pom.
参考 错误原因 过滤器或拦截器在生效时,redisTemplate还没有注入 解决方案:在注入容器时就生效 @Component //项目运行时就注入Spring容器 public class RedisBean { @Resource private RedisTemplate&lt;String
使用vite构建项目报错 C:\Users\ychen\work&gt;npm init @vitejs/app @vitejs/create-app is deprecated, use npm init vite instead C:\Users\ychen\AppData\Local\npm-
参考1 参考2 解决方案 # 点击安装源 协议选择 http:// 路径填写 mirrors.aliyun.com/centos/8.3.2011/BaseOS/x86_64/os URL类型 软件库URL 其他路径 # 版本 7 mirrors.aliyun.com/centos/7/os/x86
报错1 [root@slave1 data_mocker]# kafka-console-consumer.sh --bootstrap-server slave1:9092 --topic topic_db [2023-12-19 18:31:12,770] WARN [Consumer clie
错误1 # 重写数据 hive (edu)&gt; insert overwrite table dwd_trade_cart_add_inc &gt; select data.id, &gt; data.user_id, &gt; data.course_id, &gt; date_format(
错误1 hive (edu)&gt; insert into huanhuan values(1,&#39;haoge&#39;); Query ID = root_20240110071417_fe1517ad-3607-41f4-bdcf-d00b98ac443e Total jobs = 1
报错1:执行到如下就不执行了,没有显示Successfully registered new MBean. [root@slave1 bin]# /usr/local/software/flume-1.9.0/bin/flume-ng agent -n a1 -c /usr/local/softwa
虚拟及没有启动任何服务器查看jps会显示jps,如果没有显示任何东西 [root@slave2 ~]# jps 9647 Jps 解决方案 # 进入/tmp查看 [root@slave1 dfs]# cd /tmp [root@slave1 tmp]# ll 总用量 48 drwxr-xr-x. 2
报错1 hive&gt; show databases; OK Failed with exception java.io.IOException:java.lang.RuntimeException: Error in configuring object Time taken: 0.474 se
报错1 [root@localhost ~]# vim -bash: vim: 未找到命令 安装vim yum -y install vim* # 查看是否安装成功 [root@hadoop01 hadoop]# rpm -qa |grep vim vim-X11-7.4.629-8.el7_9.x
修改hadoop配置 vi /usr/local/software/hadoop-2.9.2/etc/hadoop/yarn-site.xml # 添加如下 &lt;configuration&gt; &lt;property&gt; &lt;name&gt;yarn.nodemanager.res