@JsonProperty和@JsonAlias的区别
@JsonProperty
这个注解提供了序列化和反序列化过程中该java属性所对应的名称
@JsonAlias
这个注解只只在反序列化时起作⽤，指定该java属性可以接受的更多名称
public static void main (String[] args ) throws IOException {
String a ="{\"NaMe\":\"hello\"}";
ObjectMapper objectMapper = new ObjectMapper();
Label label = adValue(a, Label.class);
String labelString = objectMapper.writeValueAsString(label);
System.out.println(labelString);
}
public static class Label{
//反序列化时两个都可⽤，都没有会报错
//@JsonAlias("NaMe")
@JsonProperty("NaMe")
public String name;
public Label(){
}
}
使⽤@JsonProperty时，序列化结果为：{“NaMe”:“hello”}
使⽤@JsonAlias时，序列化结果为：{“name”:“hello”}
参考：.
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.annotation.JSONField;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.Data;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
import java.util.Objects;
import static api.Assertions.assertThat;
/
**
* Java序列化就是指把Java对象转换为字节序列的过程
* Java反序列化就是指把字节序列恢复为Java对象的过程
*
* @author: cheng.tang
* @date: 2020/7/1
* @see
* @since
*/
@Data
public class CustomFiledNameTest {
private CustomField customField;
@Before
public void setUp() {
customField = new CustomField();
customField.setFastJsonCustomField("fastJsonCustomField");
customField.setJacksonCustomField("jacksonCustomField");
json检查customField.setTwoTypeCustomField("twoTypeCustomField");
}
@Test
public void ObjectMapperSceneTest() throws IOException {
ObjectMapper objectMapper = new ObjectMapper();
String actual = objectMapper.writeValueAsString(customField);
/**
* expected：加了@JsonProperty的序列化结果中的字段名都是⾃定义的那个
*/
String expected = "{\"fastJsonCustomField\":\"fastJsonCustomField\",\"jacksonFormatOnly\":\"jacksonCustomField\",\"jacksonFormatWithTwo\":\"twoTypeCustomField\"}";
/**
* 检查序列化时 JsonProperty时是否有⽤
*/
assertThat(actual).isEqualTo(expected);
CustomField customField = adValue(actual, CustomField.class);
/**
* 反序列化场景
*/
assertThat(Objects.equals(getCustomField(), customField)).isTrue();
/**
* 序列化场景
*/
assertThat(Objects.equals(actual, objectMapper.writeValueAsString(customField))).isTrue();
}
/**
* 发现fastjson和jackson序列化java对象时，字段的顺序不同
*/
@Test
public void fastJsonSceneTest() {
String actual = JSONString(customField);
System.out.println(actual);
/**
* expected：加了@JSONField的序列化结果中的字段名都是⾃定义的那个
*/
String expected = "{\"fastJsonFormatOnly\":\"fastJsonCustomField\",\"fastJsonFormatWithTwo\":\"twoTypeCustomField\",\"jacksonCustomField\":\"jacksonCustomField\"}";
/**
* 检查序列化时 @JSONField时是否有⽤
*/
assertThat(actual).isEqualTo(expected);
CustomField customField = JSON.parseObject(actual, CustomField.class);
/**
* 反序列化场景
*/
assertThat(Objects.equals(getCustomField(), customField)).isTrue();
/**
* 序列化场景
*/
assertThat(Objects.equals(actual, JSONString(customField))).isTrue();
}
}
@Data
class CustomField {
@JsonProperty("jacksonFormatOnly")
private String jacksonCustomField;
@JSONField(name = "fastJsonFormatOnly")
private String fastJsonCustomField;
@JsonProperty("jacksonFormatWithTwo")
@JSONField(name = "fastJsonFormatWithTwo")
private String twoTypeCustomField;
}