将MySql datetime映射到hibernate

Question

I have a datetime field in my MySql database. A typical entry looks like this: 2015-08-26 11:45:48 .

But by the time it reaches my app the hours, minutes and seconds are always 00:00:00 .

This is the mapping entry:

<property name="listingTime" column="listing_time"/>         

The field in my Java class is

private java.sql.Timestamp startTime;

I tried setting various types for the listingTime property in my hibernate.cfg.xml but it doesn't change the all zeroes. What am I missing?

Answer 1

Better use annotations like this:

...
@Column
@Type(type="timestamp")
private Date listing_time;

OR you can do it this way, and if you don't want it to change see the "updateable"

@Column(name = "created", nullable = false, updatable=false)
@Temporal(TemporalType.TIMESTAMP)
private Date created;

Answer 2

With JPA, Use temporal.

<entity class="com.package.of.my.entities.MyEntity" name="MyEntity">
    <attributes>
        <basic name="startTime">
            <temporal>TIMESTAMP</temporal>
        </basic>
    </attributes>
</entity>

With Hibernate (hbm.xml), User

<hibernate-mapping package="com.package.of.my.entities">
    <class name="MyEntity">
        <timestamp name="startTime" column="START_TIME" />
    </class>
</hibernate-mapping>

Or in annotation

@Basic
@Temporal(TemporalType.TIMESTAMP)
private java.sql.Timestamp startTime;

Alternatively is to use Long datatype to store your timestamp. So, using annotation, you declare in your entity :

@Basic
private Long startTime;

public void setStartTime(Long startTime) {
    this.startTime = startTime;
}

public Long getStartTime() {
    return startTime;
}

and in your logic, you do

Date dateStartTime = new Date();
entity.setStartTime(dateStartTime.getTime());

To set the date property...and

Date dateStartTime = new Date(entity.getStartTime());

To get the date property.