尝试使用Jackson的ObjectMapper类手动将JSON字符串转换为对象，给出具体代码以及它的依赖

使用Jackson的ObjectMapper类可以很方便地将JSON字符串转换为Java对象。以下是一个示例代码：

import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.IOException;

public class JsonToObject {
    public static void main(String[] args) throws IOException {
        String jsonString = "{\"name\":\"John\",\"age\":30,\"city\":\"New York\"}";

        ObjectMapper objectMapper = new ObjectMapper();
        Person person = objectMapper.readValue(jsonString, Person.class);

        System.out.println(person.getName()); // John
        System.out.println(person.getAge()); // 30
        System.out.println(person.getCity()); // New York
    }
}

class Person {
    private String name;
    private int age;
    private String city;

    // getters and setters

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }
}

上述代码将JSON字符串 `{"name":"John","age":30,"city":"New York"}` 转换为 `Person` 对象，并打印出了对象中的属性值。

需要注意的是，使用Jackson需要添加相应的依赖，以下是Maven项目中的配置：

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.3</version>
</dependency>