JDBC MySQL connection using Unix Socket
If you want to use UNIX sockets with the Mysql JDBC Connector/J you need to provide a socketFactory.
jdbc:mysql:///?user=test&password=test&socketFactory=<classname>&<socket>=/tmp/mysql.sock
So this will vary with the implementation you use. By default, Mysql does not ship with any implementation for that, just provides an example for such a factory in it's source-code.
There is an existing UNIX socket Java library named junixsocket which also has such a socketFactory class implementation. An example is outlined in Connecting to a MySQL database via Unix Domain Sockets which is part of their documentation.
You can find more Java UNIX socket library alternatives in related Q&A material:
You simply cannot do this: the MySQL JDBC driver only supports TCP/IP and - on Windows - named pipes to connect to the database. Therefor specifying --skip-networking will not allow you to use JDBC MySQL Connector/J at all.
See also http://lists.mysql.com/java/8749:
Java itself doesn't support unix domain sockets, but since you're on windows, you can use named pipes, [..]
The dead-link in the above post is now http://dev.mysql.com/doc/connector-j/en/connector-j-reference-configuration-properties.html
The JDBC Driver from the MariaDB project supports Unix domain sockets while remaining compatible with the MySQL Connector/J JDBC driver. Example jdbc url for the MariaDB driver is: jdbc:mariadb://localhost:3306/revmgt?localSocket=/var/run/mysqld/mysqld.sock
Worth noting that this requires including the JNA library as the MariaDB driver uses domain sockets via JNA internally. I saw speed improvements for CPU bound java processes when using the unix domain sockets. I believe this was largely from the offload of work from the java process to native code freeing up CPU cycles for the already CPU bottle necked java process.