嵌套对象转map

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嵌套对象转map,当对象嵌套层次太深，获取子对象的值及其不便，为解决这一问题，于是对象转map，有key就能得到相应的value。

解决复杂json情况，尤其是当第三方json过于复杂时候很适合，如央行征信报告等。
1.嵌套对象转map方法
该方法把嵌套对象转为单层map。

Map<String, Object> map = ObjectToMapUtils.trfMap(json, ".");

2.获取嵌套对象值

该方法不需要转为map，直接配置相关的key,获取对应的value。

//获取对象相应值,key中无数组情况
String condition = "[{\"key\": \"data.page.current\"}]";
List<SearchCondition> conditions = JSON.parseArray(condition, SearchCondition.class);
Object value = ObjectToMapUtils.getObjValue(json, conditions, null);
//输出 1
System.out.println(value);

//获取对象对应value值的数组
condition = "[{\"key\": \"data.rows.name\", \"value\":\"流程步骤名称\"}]";
conditions = JSON.parseArray(condition, SearchCondition.class);
Object obj = ObjectToMapUtils.getObjValue(json, conditions, null);
System.out.println(obj);

代码如下:

    //测试json,可以为一个Object对像
    String json = "{\"success\":0,\"errorMsg\":\"错误消息\",\"data\":{\"total\":\"总记录数\",\"page\":{\"size\":10,\"current\":1},\"rows\":[{\"id\":\"任务ID\",\"workName\":\"任务名称\",\"assigneeName\":\"经办人姓名\",\"name\":\"流程步骤名称\",\"processInstanceInitiatorName\":\"发起人\",\"processInstanceStartTime\":\"发起时间\",\"createTime\":\"到达时间\",\"dueDate\":\"截止时间\"},{\"id\":\"ID\",\"workName\":\"名称\",\"assigneeName\":\"经办人\",\"name\":\"流程\",\"processInstanceInitiatorName\":\"发起人\",\"processInstanceStartTime\":\"发起\",\"createTime\":\"到达\",\"dueDate\":\"截止\"}]}}";

    //转map，connector自定义，表示嵌套对象key与key的连接
    Map<String, Object> map = ObjectToMapUtils.trfMap(json, ".");

    //获取map值
    //输出 {data.page.current=1, data.page.size=10, data={"total":"总记录数","page":{"current":1,"size":10},"rows":[{"assigneeName":"经办人姓名","processInstanceStartTime":"发起时间","createTime":"到达时间","processInstanceInitiatorName":"发起人","dueDate":"截止时间","name":"流程步骤名称","id":"任务ID","workName":"任务名称"},{"assigneeName":"经办人","processInstanceStartTime":"发起","createTime":"到达","processInstanceInitiatorName":"发起人","dueDate":"截止","name":"流程","id":"ID","workName":"名称"}]}, success=0, data.total=总记录数, data.rows=[{"assigneeName":"经办人姓名","processInstanceStartTime":"发起时间","createTime":"到达时间","processInstanceInitiatorName":"发起人","dueDate":"截止时间","name":"流程步骤名称","id":"任务ID","workName":"任务名称"},{"assigneeName":"经办人","processInstanceStartTime":"发起","createTime":"到达","processInstanceInitiatorName":"发起人","dueDate":"截止","name":"流程","id":"ID","workName":"名称"}], errorMsg=错误消息}
    System.out.println(map);
     //输出 10
    System.out.println(map.get("data.page.size"));

    //获取对象相应值,key中无数组情况
    String condition = "[{\"key\": \"data.page.current\"}]";
    List<SearchCondition> conditions = JSON.parseArray(condition, SearchCondition.class);
    Object value = ObjectToMapUtils.getObjValue(json, conditions, null);
     //输出 1
    System.out.println(value);

    //获取对象对应value值的数组
    condition = "[{\"key\": \"data.rows.name\", \"value\":\"流程步骤名称\"}]";
    conditions = JSON.parseArray(condition, SearchCondition.class);
    Object obj = ObjectToMapUtils.getObjValue(json, conditions, null);
    System.out.println(obj);

    //获取对象对应value值的数组
    condition = "[{\"key\": \"data.rows.processInstanceInitiatorName\", \"value\":\"发起人\"}]";
    conditions = JSON.parseArray(condition, SearchCondition.class);
    obj = ObjectToMapUtils.getObjValue(json, conditions, null);
    System.out.println(obj);

    map = ObjectToMapUtils.trfMap(json, "-");
    System.out.println(map);
    System.out.println(map.get("data-page-size"));

详细使用见demo第4点。
demo地址:https://github.com/13162576590/fastjson_demo