problems with connecting to Oracle DB in NetBeans
I have a problem when trying to connect to Oracle DB in NetBeans. I've downloaded the Oracle Jar files like ocrs12.jar, ojdbc14.jar, ojdbc14dms.jar, orai18n.jar, and also I have built a new driver where I've added those four Jar files.
The problem is when I try to use this Oracle driver with the URL 'jdbc: oracle:thin:@//localhost:1527/sample', I always get a error message saying 'unable to get a connection,cannot establish a connection to jdbc: oracle:thin:@//localhost:1527/sample using oracle.jdbc.driver.OracleDriver(Io exception:The Network Adapter cannot establish the connection)'!!
Can anyone tell me what the problem is? Did I miss some Jar files or was the URL pattern incorrect? Please help, it's urgent!!!!!!!!! Many many thanks