Some common reasons that setup/connection issues occur are:
The database and/or listener are not started.
The driver jar file, oraclesalescloud.jar, is not defined on your class path. If the driver is not defined on your class path, you will receive a class not found exception when trying to load the driver. See "Setting the Class Path" for details.
The JDBC driver’s connection properties are not set correctly in the connection URL or data source. See "Configuring a Data Source" for more information. For example, the host name or port number are not correctly configured.
The database and/or listener are not started.