Information from within a Bean? Auto Increment

Question

I am currently using 9iAS as my app server and Oracle as my db for a project. In order to get the next PK in a CMP bean I have created the code snippet below. What I was wondering is it possible to get the Initial Context Factory, the Security Principal, the Security Credential, the Provider Url, and the Data Source Name from within the CMP Bean, so I wouldn't have to pass them in or hard code? Maybe through the handle perhaps?
public static long getNextPK(String initialContextFactory, String securityPrincipal, String _securityCredential,
String providerUrl, String dataSourceName, String _sequenceName) throws Exception
long l = 0l;
Statement st = null;
Connection con = null;
Hashtable env = new Hashtable();
try
env.put(Context.INITIAL_CONTEXT_FACTORY, _initialContextFactory);
env.put(Context.SECURITY_PRINCIPAL, _securityPrincipal);
env.put(Context.SECURITY_CREDENTIALS, _securityCredential);
env.put(Context.PROVIDER_URL, _providerUrl);
Context context = new InitialContext(env);
DataSource ds = (DataSource)context.lookup(_dataSourceName);
con = ds.getConnection();
String query = "SELECT " + _sequenceName + ".NEXTVAL FROM dual";
st = con.createStatement();
ResultSet rs = st.executeQuery(query);
if(rs.next())
l = rs.getInt(1);
if(!rs.wasNull())
//System.out.println("getNextPK() returned "+ l);
rs.close();
catch(NamingException ne)
//ne.printStackTrace();
log.error("Naming Exception: ", ne );
catch(SQLException se)
log.error("SQLException: ", se );
throw new Exception(se.getMessage());
finally
try
if(st != null)
st.close();
if(con != null)
con.close();
catch(SQLException sqe)
//sqe.printStackTrace();
log.error("SQLException: ", sqe );
return l;
}

Answer 1

For Oracle 9ias the documentation says:
Defining an Auto-Generated Primary Key
If you specify a java.lang.Object as the primary key class type in <prim-key-class>, but do not specify the primary key name in <primkey-field>, then the primary key is auto-generated by the container.
For eg.
<enterprise-beans>
<entity>
<display-name>Employee</display-name>
<ejb-name>EmployeeBean</ejb-name>
<local-home>employee.EmployeeLocalHome</local-home>
<local>employee.EmployeeLocal</local>
<ejb-class>employee.EmployeeBean</ejb-class>
<persistence-type>Container</persistence-type>
<prim-key-class>java.lang.Object</prim-key-class>
<reentrant>False</reentrant>
<cmp-version>2.x</cmp-version>
<abstract-schema-name>Employee</abstract-schema-name>
<cmp-field><field-name>empNo</field-name></cmp-field>
<cmp-field><field-name>empName</field-name></cmp-field>
<cmp-field><field-name>salary</field-name></cmp-field>
</entity>
</enterprise-beans>
Once defined, the container creates a column called autoid in the entity bean table for the primary key of type LONG. The container uses random numbers for the primary key values.
WHAT I DONT LIKE or probably not aware of is the disconnect between the oracle DB generated sequence and the container using random numbers to generated prim keys. If 9ias can auto generate a random number then I feel it should also allow us to specify what sequence from the DB if any, we would like to use... thats my 2cents worth