java - 循环遍历嵌套 JSON 数组，获取具有相同对象模型的子级

Question

我有一个如下所示的 JSON 响应:

[
    {
        "id": 5,
        "user_id": 1,
        "message": "Hello",
        "children": [
            {
                "id": 7,
                "user_id": 2,
                "message": "Hi",
                "children": [
                    {
                        "id": 8,
                        "user_id": 3,
                        "message": "Hey",
                        "children": [

                        ]
                    }
                ]
            }
        ]
    },
    {
        "id": 6,
        "user_id": 4,
        "message": "Ahoy",
        "children": [

        ]
    }
]

我已经创建了模型 ( Message.java )。调用getChildren()即可找回 child 。响应保存在列表 List<Message> messages 中.

如何循环遍历此 JSON 数组以获取每个子项的内容，直到没有子项为止？如果没有递归函数，这可能吗？

Answer 1

我假设您有列表消息:

以下是如何使用递归和迭代方式浏览所有子项:

List<Message> messages = //you already have that

System.out.println("Using Recusion : ");

for (Message message : messages) {
    printMessage(message);
}

System.out.println("Using Iterative : ");

Stack<Message> stack = new Stack<>();
stack.addAll(messages);

while (!stack.empty()) {
    Message item = stack.pop();
    System.out.println(item.getId() + ":" + item.getUser_id() + ":" + item.getMessage());
    for (Message chidren : item.getChildren()) {
        stack.push(chidren);
    }
}

这是 printMessage 方法:

public static void printMessage(Message pmessage) {
    System.out.println(pmessage.getId() + ":" + pmessage.getUser_id() + ":" + pmessage.getMessage());
    for (Message message : pmessage.getChildren()) {
        printMessage(message);
    }
}