Java Database Connectivity (JDBC)

I am new and having a problem trying to use Jconnect with the sybase database on my PC. I got an exception as follows after run in JBuilder for the connection code like this:
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Connection conn = DriverManager.getConnection("jdbc:sybase:Tds:localhost:7878", userid, password);
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java.sql.SQLException: JZ006: Caught IOException: java.net.ConnectException: Connection refused: connect

at com.sybase.jdbc2.jdbc.ErrorMessage.raiseError(ErrorMessage.java:448)

at com.sybase.jdbc2.tds.Tds.handleIOE(Tds.java:2804)

at com.sybase.jdbc2.tds.Tds.login(Tds.java:338)

at com.sybase.jdbc2.jdbc.SybConnection.tryLogin(SybConnection.java:213)

at com.sybase.jdbc2.jdbc.SybConnection.regularConnect(SybConnection.java:190)

at com.sybase.jdbc2.jdbc.SybConnection.<init>(SybConnection.java:169)

at com.sybase.jdbc2.jdbc.SybConnection.<init>(SybConnection.java:122)

at com.sybase.jdbc2.jdbc.SybDriver.connect(SybDriver.java:175)

at java.sql.DriverManager.getConnection(DriverManager.java:512)

at java.sql.DriverManager.getConnection(DriverManager.java:171)

at dbtest.DBConnect.main(DBConnect.java:56)

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I think the main issue here is the port on my localhost, how to define or get the correct the port???


Thanks

czh123