在 Java 中使用 Jackson 的 @JsonView 注释的重要性?
javajsonobject oriented programmingprogramming
JsonView 注释 可用于在序列化和反序列化过程中动态包含/排除属性。我们需要配置一个 ObjectMapper 类,以包含用于使用 writerWithView() 方法从 Java 对象编写 JSON 的视图类型。
语法
@Target(value={ANNOTATION_TYPE,METHOD,FIELD}) @Retention(value=RUNTIME) public @interface JsonView
示例
import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.annotation.JsonView; import com.fasterxml.jackson.core.JsonProcessingException; public class JsonViewAnnotationTest { public static void main(String args[]) throws JsonProcessingException { ObjectMapper objectMapper = new ObjectMapper(); String jsonString = objectMapper.writerWithView(Views.Public.class).writeValueAsString(new Person()); String jsonStringInternal = objectMapper.writerWithView(Views.Internal.class).writeValueAsString(new Person()); System.out.println(jsonString); System.out.println(jsonStringInternal); } } // Person class class Person { @JsonView(Views.Public.class) public long personId = 115; @JsonView(Views.Public.class) public String personName = "Raja Ramesh"; @JsonView(Views.Internal.class) public String gender = "male"; @Override public String toString() { return "Person{" + "personId=" + personId + ", personName='" + personName + '\'' + ", gender='" + gender + '\'' + '}'; } } class Views { static class Public {} static class Internal extends Public {} }
输出
{"personId":115,"personName":"Raja Ramesh"} {"personId":115,"personName":"Raja Ramesh","gender":"male"}