# java
> Java Application Launcher.
- Execute a java .class file that contains a main method by using just the class name:
`java {{classname}}`
- Custom input and output files. Preferably .txt files. This is useful when you don’t want to input from keyboard every time you run your class. Outputs from `System.out.println();` are saved in the output file:
`java {{classname}} <{{path/to/inputfile}}> {{path/to/outputfile}}`
- Execute a .jar program:
`java -jar {{filename.jar}}`
- Display JDK, JRE and HotSpot versions:
`java -version`
