通过java访问json最内层的值。

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.5</version>
</dependency>

{
  "name": "John",
  "age": 30,
  "address": {
    "city": "New York",
    "country": "USA"
  }
}

public class Person {
    private String name;
    private int age;
    private Address address;

    // getters and setters
}

public class Address {
    private String city;
    private String country;

    // getters and setters
}

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class Main {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\",\"age\":30,\"address\":{\"city\":\"New York\",\"country\":\"USA\"}}";

        try {
            ObjectMapper objectMapper = new ObjectMapper();
            JsonNode rootNode = objectMapper.readTree(json);

            // 访问最内层的值
            String city = rootNode.get("address").get("city").asText();
            String country = rootNode.get("address").get("country").asText();

            System.out.println("City: " + city);
            System.out.println("Country: " + country);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}