@JsonTypeInfo
和@JsonSubTypes
注解在Jackson中用于什么?
public class Lion extends Animal {
private String name;
@JsonCreator
public Lion(@JsonProperty("name") String name) {
this.name = name;
}
public String getName() {
return name;
}
public String getSound() {
return "Roar";
}
public String getType() {
return "carnivorous";
}
public boolean isEndangered() {
return true;
}
@Override
public String toString() {
return "Lion [name=" + name + ", getName()=" + getName() + ", getSound()=" + getSound() + ", getType()=" + getType() + ", isEndangered()="
+ isEndangered() + "]";
}
}
========================================
public class Elephant extends Animal {
@JsonProperty
private String name;
@JsonCreator
public Elephant(@JsonProperty("name") String name) {
this.name = name;
}
public String getName() {
return name;
}
public String getSound() {
return "trumpet";
}
public String getType() {
return "herbivorous";
}
public boolean isEndangered() {
return false;
}
@Override
public String toString() {
return "Elephant [name=" + name + ", getName()=" + getName() + ", getSound()=" + getSound() + ", getType()=" + getType()
+ ", isEndangered()=" + isEndangered() + "]";
}
}
==============================================
@JsonTypeInfo (use = JsonTypeInfo.Id.CLASS, include = As.PROPERTY, property = "classNameExtenral")
@JsonSubTypes ({@Type (value = Lion.class, name = "lion"), @Type (value = Elephant.class, name = "elephant")})
public abstract class Animal {
@JsonProperty ("name")
String name;
@JsonProperty ("sound")
String sound;
@JsonProperty ("type")
String type;
@JsonProperty ("endangered")
boolean endangered;
}
public static void main(String[] args){
Lion lion = new Lion("Simba");
Elephant elephant = new Elephant("Manny");
List<Animal> animals = new ArrayList<>();
animals.add(lion);
animals.add(elephant);
}
我的理解是,它除了保存实际数据之外,还保留了被序列化对象的具体类型。
对我来说不清楚的是,反序列化过程中的实际优势/收益是什么。
除了Java文档之外,没有获得任何重要的文档。有人可以帮忙或提供相关文档吗?