如何使用Jackson anotations在java Map中展开键和值对象？

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.4</version>
</dependency>

Map<String, Student> studentMap = new HashMap<>();
studentMap.put("John", new Student("John", 20));
studentMap.put("Jane", new Student("Jane", 22));

public class Student {
    @JsonProperty("name")
    private String name;

    @JsonProperty("age")
    private int age;

    // 构造函数、getter和setter方法省略
}

ObjectMapper objectMapper = new ObjectMapper();
String json = objectMapper.writeValueAsString(studentMap);
System.out.println(json);

{
  "John" : {
    "name" : "John",
    "age" : 20
  },
  "Jane" : {
    "name" : "Jane",
    "age" : 22
  }
}