@JsonSerializer
- 全局类型重写,如:Date,对所有 Date 类型毫秒级转换到秒级。
package com.imooc.utils.serializer;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import java.io.IOException;
import java.util.Date;
public class Date2LongSerializer extends JsonSerializer<Date> {
@Override
public void serialize(Date date, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException, JsonProcessingException {
jsonGenerator.writeNumber(date.getTime() / 1000);
}
}
package com.imooc.dto;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.imooc.dataobject.OrderDetail;
import com.imooc.enums.OrderStatusEnum;
import com.imooc.enums.PayStatusEnum;
import com.imooc.utils.EnumUtil;
import com.imooc.utils.serializer.Date2LongSerializer;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
@Data
public class OrderDTO {
/** 创建时间. */
@JsonSerialize(using = Date2LongSerializer.class)
private Date createTime;
/** 更新时间. */
@JsonSerialize(using = Date2LongSerializer.class)
private Date updateTime;
}
@JsonInclude
- 使得返回为 null 的字段不显示在前台。
1、注解用法,@JsonSerializer 或 @JsonInclude
package com.imooc.dto;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.imooc.dataobject.OrderDetail;
import com.imooc.enums.OrderStatusEnum;
import com.imooc.enums.PayStatusEnum;
import com.imooc.utils.EnumUtil;
import com.imooc.utils.serializer.Date2LongSerializer;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
@Data
//@JsonSerialize(include = JsonSerialize.Inclusion.NON_NULL) // 已过期,可以用下面这条
@JsonInclude(JsonInclude.Include.NON_NULL)
public class OrderDTO {
//...
}
2、yml 配置
spring:
jackson:
default-property-inclusion: non_null
@JsonIgnore
- 忽略被注解的字段一定不会显示在前台。
package com.imooc.dto;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.imooc.dataobject.OrderDetail;
import com.imooc.enums.OrderStatusEnum;
import com.imooc.enums.PayStatusEnum;
import com.imooc.utils.EnumUtil;
import com.imooc.utils.serializer.Date2LongSerializer;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
@Data
public class OrderDTO {
@JsonIgnore
public OrderStatusEnum getOrderStatusEnum() {
return EnumUtil.getByCode(orderStatus, OrderStatusEnum.class);
}
@JsonIgnore
public PayStatusEnum getPayStatusEnum() {
return EnumUtil.getByCode(payStatus, PayStatusEnum.class);
}
}