Hi,
I'm trying to persist a field of type java.sql.Timestamp to a column of type datetime in sql server 2005. I get an exception :
java.lang.UnsupportedOperationException: cannot perform lookups on timestamps. The field i'm trying to persist is a part of a composite primary key.
I tried running the query directly. it didn't give me any error. So I think the problem is with the primary key class that creates the hash code for the key.
Can I have a timestamp as a part of the key. Does it creates a problem when creating the hash code?

Hibernate version: 3.0

Mapping documents:
<hibernate-mapping package="com.test.pas.common">

<class
name="FluClinic"
table="FluClinic"
dynamic-insert="true"
dynamic-update="true"
>

<composite-id class="com.test.pas.common.keys.FluClinicPK" name="fluClinicPK">


<key-property
name="enteredBy"
type="com.test.pas.common.customtypes.TrimmedString"
column="EnteredBy"
/>

<key-property
column="Enter_TS"
name="enterTimeStamp"
type="timestamp"
/>

<key-property name="HRN"
type="com.test.pas.common.customtypes.TrimmedString">
<column name="HRN" sql-type="character(9)" not-null="true" />
</key-property>

</composite-id>

<property
name="enteredBy"
type="com.test.pas.common.customtypes.TrimmedString"
access="property"
column="EnteredBy"
insert="false"
update="false"
/>


<property
column="Enter_TS"
name="enterTimeStamp"
type="timestamp"
access="property"
insert="false"
update="false"
/>

<property
column="Uploaded_TS"
name="uploadedTimeStamp"
type="timestamp"
access="property"
insert="true"
update="true"
/>

<property
name="HRN"
type="com.test.pas.common.customtypes.TrimmedString"
access="property"
column="HRN"
insert="false"
update="false"
/>


Full stack trace of any exception that occurs:

12:13:55,110 WARN [RequestProcessor] Unhandled Exception thrown: class java.lang.UnsupportedOperationException
12:13:55,110 WARN [RequestProcessor] Unhandled Exception thrown: class java.lang.UnsupportedOperationException
12:13:55,120 ERROR [[action]] Servlet.service() for servlet action threw exception
java.lang.UnsupportedOperationException: cannot perform lookups on timestamps
at org.hibernate.type.TimestampType.getHashCode(TimestampType.java:98)
at org.hibernate.type.AbstractType.getHashCode(AbstractType.java:113)
at org.hibernate.type.ComponentType.getHashCode(ComponentType.java:199)
at org.hibernate.engine.EntityKey.getHashCode(EntityKey.java:65)
at org.hibernate.engine.EntityKey.<init>(EntityKey.java:38)
at org.hibernate.event.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:135)
at org.hibernate.event.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:106)
at org.hibernate.event.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:180)
at org.hibernate.event.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:31)
at org.hibernate.event.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:169)
at org.hibernate.event.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:25)
at org.hibernate.event.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:65)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:479)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:474)


Name and version of the database you are using: SQL SERVER 2005

PrimaryKey class

public class FluClinicPK implements Serializable
{

private static final long serialVersionUID = 1L;

// private int hashValue = 0;

private String HRN;
private String enteredBy;
private Timestamp enterTimeStamp;

public FluClinicPK( )
{
// used for hibernate
}


public FluClinicPK( String enteredBy, Timestamp enterTimeStamp, String HRN )
{
this.enteredBy = enteredBy;
this.enterTimeStamp = enterTimeStamp;
this.HRN = HRN;
}

/**
* Implementation of the equals comparison on the basis of equality of the Id components.
*
*/

public boolean equals( Object o )
{
if ( this == o ) return true;
if ( o == null ) return false;
if ( !(o instanceof FluClinicPK) ) return false;
final FluClinicPK fluClinicPK = (FluClinicPK) o;

if ( !enteredBy.equals( fluClinicPK.getEnteredBy( ) ) ) return false;
if ( !enterTimeStamp.equals( fluClinicPK.getEnterTimeStamp( ) ) ) return false;
if ( !HRN.equals( fluClinicPK.getHRN( ) ) ) return false;
return true;
}


public int hashCode( )
{
return (getEnteredBy( ) + getEnterTimeStamp( )+ getHRN( )).hashCode( );
}
// other getters and setters.
}


Please lemme know if I'm doing things correctly.


Thanks,
Anand.

I am having a similar problem. I am using Sybase ASE. I have date fields stores as Timestamp. In my Hibernate mapping files I have set the "type" as java.sql.Timestamp. When I try to retrieve objects I get the following exception. The following was thrown when I had requested all rows of a table to bereturned (i.e. there was no where clause). How do I specify the Timestamp format (without changing anyting on the database )


When i retreive objecs that have a timestamp as part of their composit ekey I get an exception. ANd when I try to retreive ALL objects (as explained above) I get the follwing exception.