I defined a class:
import com.sun.rowset.*;
import java.sql.*;
public class RowSetAdaptor extends java.lang.Object implements java.io.Serializable
{
private String s;
private CachedRowSetImpl rowset;
public RowSetAdaptor()
{
try{
rowset = new CachedRowSetImpl();
}catch(Exception e){System.out.println("constructor:"+e);}
}
I put this class file in a jar and put this jar in the C:\jboss-3.2.3\server\default\lib
in my code,I use this class:
RowSetAdaptor rs = new RowSetAdaptor();
or
RowSetAdaptor rs = null;
rs = new RowSetAdaptor();
the first time after start jboss,I get error:
constructor:java.lang.NullPointerException
but this only happen on first time,if I run it again,no errors,why?looks like something not been populate in the memory for the first time.by the com.sun.rowset.* classes are in th rowset.jar which is also in C:\jboss-3.2.3\server\default\lib folder