Hibernate和JPA 2.1-將java.time.LocalDateTime映射為java.util.Map中的鍵

Question

從域模型類給出以下枚舉：

public enum OperationMode {
    BATTERY_CHANGE_MODE,
    PBP_MODE
}

我還定義了一個AttributeConverter來在LocalDateTime和TimeStamp之間轉換

@Converter
public class LocalDateTimeAttributeConverter implements AttributeConverter<LocalDateTime, Timestamp> {

   @Override
   public Timestamp convertToDatabaseColumn(LocalDateTime locDateTime) {
       return (locDateTime == null ? null : Timestamp.valueOf(locDateTime));
   }

    @Override
    public LocalDateTime convertToEntityAttribute(Timestamp sqlTimestamp) {
        return (sqlTimestamp == null ? null : sqlTimestamp.toLocalDateTime());
    }
}

在Entity類中，我需要為java.utitl.Map定義一個有效的映射作為元素集合：

@ElementCollection
@MapKeyColumn(name = "time")
@Convert(converter = LocalDateTimeAttributeConverter.class)
// some annotations are missing here...
private Map<LocalDateTime, OperationMode> operationHistory;

建議使用什么方法使它正常工作？

Answer 1

解決方案是以下映射：

@ElementCollection
@MapKeyColumn(name = "time")
@Convert(converter = LocalDateTimeAttributeConverter.class, attributeName = "key")
@Enumerated(EnumType.STRING)
private Map<LocalDateTime, OperationMode> operationHistory;

缺少attributeName'key ' 。