努力找出如何创建基于HashMap的嵌套JSON。基本上，我有一个HashMap列表，它具有非唯一的键/值对。我需要把这个HashMap列表变成一个唯一的JSON对象。
这是我试图描述的一个示例：HashMap列表如下所示：
[
{PERIOD: 201801, ID: 12345},
{PERIOD: 201801, ID: 12346},
{PERIOD: 201801, ID: 12347},
{PERIOD: 201802, ID: 12345},
{PERIOD: 201802, ID: 12347},
{PERIOD: 201803, ID: 12345},
]
我希望我的结果是：
{
"NAME": "Results",
"DETAILS": [
{
"PERIOD": 201801,
"DETAILS": [
{ "ID": 12345 },
{ "ID": 12346 },
{ "ID": 12347 }
},
{
"PERIOD": 201802,
"DETAILS": [
{ "ID": 12345 },
{ "ID": 12347 }
},
{
"PERIOD": 201803,
"DETAILS": [
{ "ID": 12345 }
}
]
}
需要注意的是，HashMap中的键/值对可以是任意数量的项目，而不是像我在上面的示例中描述的那样只有两个。我尝试过做递归函数，但我一直碰壁。
编辑：这不是这个问题的重复。我知道如何使用这些方法将HashMap序列化为JsonObject。我已经做过几次了。我在问如何逻辑地分析HashMap中的数据并基于该逻辑创建JsonObject。
编辑2：多个级别的示例：
[
{PERIOD: 201801, ID: 12345, MANAGER: "Dave"},
{PERIOD: 201801, ID: 12345, MANAGER: "Jill"},
{PERIOD: 201801, ID: 12346, MANAGER: "Dave"},
{PERIOD: 201801, ID: 12347, MANAGER: "Jon"},
{PERIOD: 201802, ID: 12345, MANAGER: "Rob"},
{PERIOD: 201802, ID: 12347, MANAGER: "Dave"},
{PERIOD: 201803, ID: 12345, MANAGER: "Bailey"},
]
以下是JSON：
{
"NAME": "Results",
"DETAILS": [
{
"PERIOD": 201801,
"DETAILS": [
{
"ID": 12345,
"DETAILS": [
"MANAGER": "Dave",
"MANAGER": "Jill"
]
},
{
"ID": 12346,
"DETAILS": [
"MANAGER": "Dave"
]
},
{
"ID": 12347,
"DETAILS": [
"MANAGER": "Jon"
]
}
},
{
"PERIOD": 201802,
"DETAILS": [
{
"ID": 12345,
"DETAILS": [
"MANAGER": "Rob"
]
},
{
"ID": 12347,
"DETAILS": [
"MANAGER": "Dave"
]
}
},
{
"PERIOD": 201803,
"DETAILS": [
{
"ID": 12345,
"DETAILS": [
"MANAGER": "Bailey"
]
}
}
]
}
解决了这个问题：
private void insertValueIntoDetails(String key, String value, JsonArray details, int targetIndex, int currentIndex) {
// if the targetIndex equals the currentIndex ?
if (targetIndex == currentIndex) {
// if details doesn't have the value, then insert it
AtomicBoolean hasValue = new AtomicBoolean(false);
details.forEach(item -> {
if (((JsonObject)item).get("ID").getAsString().equals(value.toString())) {
hasValue.set(true);
}
});
if (!hasValue.get()) {
JsonObject o = new JsonObject();
o.addProperty("ID", value);
o.add("Details", new JsonArray());
details.add(o);
}
}
// if the targetIndex > currentIndex
if (targetIndex > currentIndex) {
// call insertValueIntoDetails with key, value, details of the currentIndex, targetIndex, currentIndex + 1
JsonArray deets = getDetails(key, details, currentIndex);
insertValueIntoDetails(key, value, deets, targetIndex, currentIndex + 1);
}
}
