在 Spring/Hibernate 项目中,在我的实体类中,我有:
package klab.finance.main.entity;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import klab.backend.entity.postgres.base.BaseEntity;
import klab.backend.utils.DateTimeUtils;
import klab.backend.utils.JsonDateTime;
import klab.backend.utils.json.LocalDateTimeToTimestampDeserializer;
import klab.backend.utils.json.TimestampToLocalDateTimeSerializer;
import org.hibernate.annotations.Where;
import org.joda.time.LocalDateTime;
import javax.persistence.*;
import java.util.HashSet;
import java.util.Set;
@Entity
@Table(name="transactions")
@JsonIgnoreProperties(ignoreUnknown = true)
public class Transaction extends BaseEntity {
private Long bankTransactionDate;
@Column(name="bank_transaction_date")
@JsonSerialize(using = TimestampToLocalDateTimeSerializer.class)
public Long getBankTransactionDate(){
return bankTransactionDate;
}
@JsonDeserialize(using = LocalDateTimeToTimestampDeserializer.class)
public void setBankTransactionDate(Long bankTransactionDate){
this.bankTransactionDate=bankTransactionDate;
}
}
我的序列化器类:
package klab.backend.utils.json;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import klab.backend.entity.postgres.base.BaseEntity;
import klab.backend.utils.DateTimeUtils;
import org.joda.time.LocalDateTime;
import java.io.IOException;
public class TimestampToLocalDateTimeSerializer extends JsonSerializer<Long> {
@Override
public void serialize(Long value, JsonGenerator jsonGenerator, SerializerProvider serializerProvider)
throws IOException {
jsonGenerator.writeString("blabla");
}
}
我希望通过 "bank_transaction_date": "blabla"
获得 JSON .
相反,我通过 "bank_transaction_date": null
得到它。我还注意到,如果我在序列化器中设置断点,调试器永远不会在那里停止,所以它可能不会被使用。
怎么了?
最佳答案
答案非常简单:bankTransactionDate
为 null
,事实证明,对于 null
值,不会调用序列化器:)
当我用值填充数据库后,序列化程序开始工作并给我“bank_transaction_date”:“blabla”
。
关于java - @JsonSerialize 不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35342323/