将JSON数据解析转换为样例对象

假设有以下JSON数据：

{
  "name": "John Doe",
  "age": 30,
  "address": {
    "street": "123 Main St",
    "city": "Anytown",
    "state": "CA"
  },
  "phones": [
    {
      "type": "home",
      "number": "555-1234"
    },
    {
      "type": "work",
      "number": "555-5678"
    }
  ]
}

可以使用以下Java代码将其解析为样例对象：

import com.fasterxml.jackson.databind.ObjectMapper;

public class Example {
  public static void main(String[] args) throws Exception {
    String json = "{\"name\":\"John Doe\",\"age\":30,\"address\":{\"street\":\"123 Main St\",\"city\":\"Anytown\",\"state\":\"CA\"},\"phones\":[{\"type\":\"home\",\"number\":\"555-1234\"},{\"type\":\"work\",\"number\":\"555-5678\"}]}";
    ObjectMapper objectMapper = new ObjectMapper();
    Person person = objectMapper.readValue(json, Person.class);
    System.out.println(person);
  }
}

class Person {
  private String name;
  private int age;
  private Address address;
  private Phone[] phones;

  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 Address getAddress() {
    return address;
  }

  public void setAddress(Address address) {
    this.address = address;
  }

  public Phone[] getPhones() {
    return phones;
  }

  public void setPhones(Phone[] phones) {
    this.phones = phones;
  }

  @Override
  public String toString() {
    return "Person{" +
        "name='" + name + '\'' +
        ", age=" + age +
        ", address=" + address +
        ", phones=" + Arrays.toString(phones) +
        '}';
  }
}

class Address {
  private String street;
  private String city;
  private String state;

  public String getStreet() {
    return street;
  }

  public void setStreet(String street) {
    this.street = street;
  }

  public String getCity() {
    return city;
  }

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

  public String getState() {
    return state;
  }

  public void setState(String state) {
    this.state = state;
  }

  @Override
  public String toString() {
    return "Address{" +
        "street='" + street + '\'' +
        ", city='" + city + '\'' +
        ", state='" + state + '\'' +
        '}';
  }
}

class Phone {
  private String type;
  private String number;

  public String getType() {
    return type;
  }

  public void setType(String type) {
    this.type = type;
  }

  public String getNumber() {
    return number;
  }

  public void setNumber(String number) {
    this.number = number;
  }

  @Override
  public String toString() {
    return "Phone{" +
        "type='" + type + '\'' +
        ", number='" + number + '\'' +
        '}';
  }
}

在这个例子中，我们使用了Jackson库来将JSON数据解析为Person对象。注意，Person类必须包含与JSON数据中的属性相对应的字段，以便Jackson可以正确解析数据。在这个例子中，Person类包含name、age、address和phones字段，分别对应JSON数据中的属性。Address和Phone类也是必需的，以便Person类可以包含嵌套属性。最后，我们使用toString方法打印解析的Person对象。