Hi Folks,

I have a help table, a primary key consists of contextid field and appid field.

But I don't know how to query.

the id is passed to query

Help.HelpId id = new Help.HelpId(new Integer(1), new Integer(99)) ;

q = sess.createQuery("from Help where hp.id = :id" )
.setParameter("id", searchKeyObj);

But I got this error.

Hibernate: select help0_.ContextID as ContextID, help0_.AppID as AppID, help0_.Path as Path1_, help0_.Title as Title1_ from tblHelp help0_ where (help0_.ContextID, help0_.AppID)=?
17:58:24,960 WARN JDBCExceptionReporter: SQL Error: 170, SQLState: 37000
17:58:24,960 ERROR JDBCExceptionReporter: Line 1: Incorrect syntax near ','.
------------- ---------------- ---------------
------------- Standard Error -----------------
org.hibernate.exception.SQLGrammarException: could not execute query
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:59)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.loader.Loader.doList(Loader.java:1564)
at org.hibernate.loader.Loader.list(Loader.java:1544)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:375)
at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:271)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:830)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:74)

----------------------------------------------------

Please help. Thank you very much!

Chwang

please also take look Help.class and Help.hbm.xml files.



<hibernate-mapping package="com.server.persistence.datamodel">

<class name="Help" table="tblHelp" lazy="true">
<composite-id name="id" class="com.server.persistence.datamodel.Help$HelpId"
access="field"
unsaved-value="none">

<key-property name="contextId"
access="field"
column="ContextID"
length="16"/>

<key-property name="appId"
access="field"
column="AppID"
length="16"/>
</composite-id>


<property name="path" type="string" column="Path" length="55" not-null="false"/>
<property name="title" type="string" column="Title" length="55" not-null="false"/>

</class>
</hibernate-mapping>


----------------------


public class Help implements Serializable,Comparable {


// ******************* Begin Inner composite Id class ******************* //
public static class HelpId implements Serializable {
public Integer contextId;
public Integer appId;

public HelpId() {}

public HelpId(Integer contextId, Integer appId) {
this.contextId = contextId;
this.appId = appId;
}

public boolean equals(Object o) {
if (o instanceof HelpId) {
HelpId that = (HelpId)o;
return this.contextId.equals(that.contextId) &&
this.appId.equals(that.appId);
} else {
return false;
}
}

public int hashCode() {
return contextId.hashCode() + appId.hashCode();
}
}
// ******************* End Inner composite Id class ******************* //

// ===============

public Help(){}

private HelpId id = new HelpId();
private String path;
private String title;

public HelpId getId()
{
return id;
}
/**
public void setHelpId(HelpId i)
{
helpId = i;
}
**/

public String getPath()
{
return path;
}

public void setPath(String s)
{
path = s;
}

public String getTitle()
{
return title;
}

public void setTitle(String s)
{
title = s;
}

public int compareTo(Object o) {

if (o instanceof Help)
return getPath().compareTo(((Help)o).getPath());
return 0;
}


}

Have you read section 5.1.5 of the ref docs?
You can use mapped ids (same section) to work around this. It involves defining a POJO for the key object. You already have the POJO, Help.HelpId. So this is the solution you want. Read that section for the gotchas involved in this solution.

Thank you,

So I tried to use in this way.

Help.HelpId hid = new Help.HelpId(new Integer(1), new Integer(99)) ;


Help ob = (Help)sess.load(Help.class, hid);

But I got the java.lang.NullPointerException at load().
I check the Help table. Actually the number are avaiable in Help table.

Do you know reason why?

Thank you very ncuh

Chwang

According to section 5.1.5, you need the fields in the composite id to be in both the composite id class (Help.HelpId) and the mapped class (Help). Sorry for not making that clearer yesterday.

Thank you very much,
With your help , I have fixed this issue.

Best Regards,

Chwang