can't connect to database

i try to connect to the database but failed.

i wrote this:
dbJDBCDriver = "oracle.jdbc.driver.OracleDriver";
dbURL = "jdbc: oracle:thin: @bigcpu025:1521:TSH1";
dbUser = "sys";
dbPwd = "database";

But i get this error:
* Start loading driver: oracle.jdbc.driver.OracleDriver
* Start connection to: jdbc: oracle:thin: @bigcpu025:1521:TSH1
* dbUser,dbPwd: oracle.jdbc.driver.OracleDriver

*An Exception has occurred... Database access failed! java.sql.SQLException: ORA-28009: connection to sys should be as sysdba or sysoper

*An Exception has occurred... Something happened on the way to heaven (ie, main) java.lang.NullPointerException
*DEBUG> main says bye!

If i do this:
dbJDBCDriver = "oracle.jdbc.driver.OracleDriver";
dbURL = "jdbc: oracle:thin: @bigcpu025:1521:TSH1";
dbUser = "sysdba";
dbPwd = "database";
i get this error:

* Start loading driver: oracle.jdbc.driver.OracleDriver
* Start connection to: jdbc: oracle:thin:@bigcpu025:1521:TSH1
* dbUser,dbPwd: oracle.jdbc.driver.OracleDriver
*An Exception has occurred... Database access failed! java.sql.SQLException: ORA-01017: invalid username/password; logon denied

*An Exception has occurred... Something happened on the way to heaven (ie, main) java.lang.NullPointerException
*DEBUG> main says bye!

i'm not sure what's the problem here.

28009 - connect sys/password is not allowed
You have to connect like this using a connect as -
connect sys/password as sysdba

But sysdba has to be allowed create process on the instance yoyu are using.

I had a problem like this once with a web application server. It turned out that I was calling the wrong JDBC driver. Make sure if your using the thin driver, and if so that it uses "Classes12.jar"

Take a look at ...\Oracle9\jdbc\readme.txt what your version of Oracle is capable of.