How do I run an Eclipse launcher file in IntelliJ IDEA?

IDEA doesn't support importing Eclipse .launch files.

A workaround is to use the third-party Eclipser plug-in.

Eclipser can convert the following Eclipse launch configurations into IntelliJ IDEA run configurations:

• Local Java application Eclipse launcher
• Program launch Eclipse launcher (converted into external tool in Tools menu)
• Maven launch configuration
• Remote Java application Eclipse launcher
• Ant launch configuration

Try the Eclipser plugin

http://plugins.jetbrains.com/plugin?pluginId=7153

Eclipser will automatically convert Eclipse launch configurations into IntelliJ IDEA configurations

However it currently (as of November 2014) supports only very limited number of launch types:

• local Java application (...)
• program launch (...)
• Maven launcher (...)

See https://github.com/kukido/eclipser/wiki for details.