📅  最后修改于: 2020-11-16 07:40:21             🧑  作者: Mango
@JsonTypeName用于设置要用于带注释的类的类型名称。
import java.io.IOException;
import com.fasterxml.jackson.annotation.JsonSubTypes;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.JsonTypeInfo.As;
import com.fasterxml.jackson.annotation.JsonTypeName;
import com.fasterxml.jackson.databind.ObjectMapper;
public class JacksonTester {
public static void main(String args[]) throws IOException {
Shape shape = new JacksonTester.Circle("CustomCircle", 1);
String result = new ObjectMapper()
.writerWithDefaultPrettyPrinter()
.writeValueAsString(shape);
System.out.println(result);
String json = "{\"name\":\"CustomCircle\",\"radius\":1.0, \"type\":\"circle\"}";
Circle circle = new ObjectMapper().readerFor(Shape.class).readValue(json);
System.out.println(circle.name);
}
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME,
include = As.PROPERTY, property = "type") @JsonSubTypes({
@JsonSubTypes.Type(value = Square.class, name = "square"),
@JsonSubTypes.Type(value = Circle.class, name = "circle")
})
static class Shape {
public String name;
Shape(String name){
this.name = name;
}
}
@JsonTypeName("square")
static class Square extends Shape {
public double length;
Square(){
this(null,0.0);
}
Square(String name, double length){
super(name);
this.length = length;
}
}
@JsonTypeName("circle")
static class Circle extends Shape {
public double radius;
Circle(){
this(null,0.0);
}
Circle(String name, double radius){
super(name);
this.radius = radius;
}
}
}
{
"type" : "circle",
"name" : "CustomCircle",
"radius" : 1.0
}
CustomCircle