如何在Java中使用@JsonCreator注释反序列化JSON字符串？
该 @JsonProperty 注解可以用于指示属性名的JSON。此批注可用于构造函数 或工厂方法。该@JsonCreator在注释中是十分有用@JsonSetter注释不能使用。例如，不可变对象没有任何设置方法，因此它们需要将其初始值注入到构造函数中。
@JsonProperty-构造函数
示例
import com.fasterxml.jackson.annotation.*;
import java.io.IOException;
import com.fasterxml.jackson.databind.*;
public class JsonCreatorTest1 {
public static void main(String[] args) throws IOException {
ObjectMapper om = new ObjectMapper();
String jsonString = "{\"id\":\"101\", \"fullname\":\"Ravi Chandra\", \"location\":\"Pune\"}";
System.out.println("JSON: " + jsonString);
Customer customer = om.readValue(jsonString, Customer.class);
System.out.println(customer);
}
}// Customer classclass Customer {
private String id;
private String name;
private String address;
public Customer() {
} @JsonCreator public Customer( @JsonProperty("id") String id, @JsonProperty("fullname") String name, @JsonProperty("location") String address) {
this.id = id;
this.name = name;
this.address = address;
} @Override public String toString() {
return "Customer [id=" + id + ", name=" + name + ", address=" + address + "]";
}
}输出结果
JSON: {"id":"101", "fullname":"Ravi Chandra", "location":"Pune"}Customer [id=101, name=Ravi Chandra, address=Pune]@JsonCreator-工厂方法
示例
import com.fasterxml.jackson.annotation.*;
import java.io.IOException;
import com.fasterxml.jackson.databind.*;
public class JsonCreatorTest2 {
public static void main(String[] args) throws IOException {
ObjectMapper mapper = new ObjectMapper();
String jsonString = "{\"id\":\"102\", \"fullname\":\"Raja Ramesh\", \"location\":\"Hyderabad\"}";
System.out.println("JSON: " + jsonString);
Customer customer = mapper.readValue(jsonString, Customer.class);
System.out.println(customer);
}
}// Customer classclass Customer {
private String id;
private String name;
private String address;
public Customer() {
} @JsonCreator public static Customer createCustomer(
@JsonProperty("id") String id, @JsonProperty("fullname") String name, @JsonProperty("location") String address) {
Customer customer = new Customer();
customer.id = id;
customer.name = name;
customer.address = address;
return customer;
} @Override public String toString() {
return "Customer [id=" + id + ", name=" + name + ", address=" + address + "]";
}
}输出结果
JSON: {"id":"101", "fullname":"Raja Ramesh", "location":"Hyderabad"}Customer [id=102, name=Raja Ramesh, address=Hyderabad]