1. MySQL
Class.forName( "org.gjt.mm.mysql.Driver" );
cn 
= DriverManager.getConnection( "jdbc:mysql://MyDbComputerNameOrIP:3306/myDatabaseName", sUsr, sPwd );

2. Microsoft SQLServer
Class.forName( "com.microsoft.jdbc.sqlserver.SQLServerDriver" );
cn 
= DriverManager.getConnection( "jdbc:microsoft:sqlserver://MyDbComputerNameOrIP:1433;databaseName=master", sUsr, sPwd );

3. Oracle
Class.forName( "oracle.jdbc.driver.OracleDriver" );
cn 
= DriverManager.getConnection( "jdbc:oracle:thin:@MyDbComputerNameOrIP:1521:ORCL", sUsr, sPwd );

4.DB2
Class.forName("com.ibm.db2.jdbc.net.DB2Driver");
String url
="jdbc:db2://192.9.200.108:6789/SAMPLE"
cn 
= DriverManager.getConnection( url, sUsr, sPwd );

5. ODBC

Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" );
Connection cn 
= DriverManager.getConnection( "jdbc:odbc:" + sDsn, sUsr, sPwd );


6. PostgreSQL

Class.forName( "org.postgresql.Driver" );
cn 
= DriverManager.getConnection( "jdbc:postgresql://MyDbComputerNameOrIP/myDatabaseName", sUsr, sPwd );