如何使用 Java 中的 Jackson 为字段定义备用名称?
javajsonobject oriented programmingprogramming
@JsonAlias 注释可以为反序列化期间接受的属性定义一个或多个备用名称，将 JSON 数据设置为 Java 对象。但在序列化时，即从 Java 对象获取 JSON，仅使用实际的逻辑属性名称，而不是别名。
语法
@Target(value={ANNOTATION_TYPE,FIELD,METHOD,PARAMETER})
@Retention(value=RUNTIME)
public @interface JsonAlias
示例
import com.fasterxml.jackson.annotation.*;
import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import java.io.*;
public class ObjectToJsonTest {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper mapper = new ObjectMapper();
Technology tech = new Technology("Java", "Oracle");
Employee emp = new Employee(110, "Raja", tech);
String jsonWriter = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(emp);
System.out.println(jsonWriter);
}
}
// Technology classclass Technology {
@JsonProperty("skill") private String skill;
@JsonProperty("subSkill") @JsonAlias({"sSkill", "mySubSkill"}) private String subSkill;
public Technology(){}
public Technology(String skill, String subSkill) {
this.skill = skill;
this.subSkill = subSkill;
}
public String getSkill() {
return skill;
}
public void setSkill(String skill) {
this.skill = skill;
}
public String getSubSkill() {
return subSkill;
}
public void setSubSkill(String subSkill) {
this.subSkill = subSkill;
}
}
// Employee classclass Employee {
@JsonProperty("empId") private Integer id;
@JsonProperty("empName") @JsonAlias({"ename", "myename"}) private String name;
@JsonProperty("empTechnology") private Technology tech;
public Employee(){}
public Employee(Integer id, String name, Technology tech){
this.id = id;
this.name = name;
this.tech = tech;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Technology getTechnology() {
return tech;
}
public void setTechnology(Technology tech) {
this.tech = tech;
}
}
输出
{
"technology" : {
"skill" : "Java",
"subSkill" : "Oracle"
},
"empId" : 110,
"empName" : "Raja",
"empTechnology" : {
"skill" : "Java",
"subSkill" : "Oracle"
}
}
