database driver link
MySQL database:
1) Driver package: https://mvnrepository.com/artifact/mysql/mysql-connector-java (download path)
2) Driver class name: com.mysql.jdbc.Driver
3) JDBC URL: jdbc:mysql://IP address: port number/database name
Note: The default port number is: 3306
SQL server2005 database:
1) Driver package: https://mvnrepository.com/artifact/com.microsoft.sqlserver/sqljdbc4 (download path)
2) Driver class name: com.microsoft.jdbc.sqlserver.SQLServerDriver
3) JDBC URL: jdbc:microsoft:sqlserver://IP address:port number;DatabaseName=database name
4) The difference between sqljdbc and sqljdbc4: https://blog.csdn.net/cainiao_M/article/details/53404222
Note: The default port number is: 1433
Oracle database:
1) Driver package: https://mvnrepository.com/artifact/com.oracle/ojdbc6 (download path)
2) Driver class name: oracle.jdbc.driver.OracleDriver
3) JDBC URL: jdbc:oracle:thin:@IP address:port number:database name
4) The difference between ojdbc6 and ojdbc14: ojdbc14.jar (suitable for java-1.4 and 1.5), ojdbc6 (suitable for java-1.6)
Note: The default port number is: 1521