Oracle - error al querer conectar un jdbc con netbeans

Hola que tal quisiera saber si alguien me puede ayudar con este error q me aparece al querer conectar mi netbeans 7.2 con ojdbc6...... desde ya gracias

Salida - Hibernate(run)

12/07/2014 22:30:10 packageDAO.hibernate.ClientDAOimp getAll
GRAVE: null
java.sql.SQLRecoverableException: Error de E/S: The Network Adapter could not establish the connection
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:489)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:553)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:254)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:528)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at packageDAO.hibernate.ClientDAOimp.getAll(ClientDAOimp.java:34)
at Principal.Principal.main(Principal.java:19)
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:439)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:454)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:693)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:251)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1140)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:340)
... 8 more
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:149)
at oracle.net.nt.ConnOption.connect(ConnOption.java:133)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:405)
... 13 more

Hola, estoy con el mismo error, que usted ha hecho para resolver ?