How to set the default jvm args to gradle application plugin?

Support for JVM arguments was added in Gradle 1.7: https://docs.gradle.org/current/userguide/application_plugin.html#configureApplicationDefaultJvmArgs

For example, for setting file.encoding, you can do:

applicationDefaultJvmArgs = ['-Dfile.encoding=utf-8']

There is currently no special support for setting DEFAULT_JVM_OPTS. However, you can do something like:

startScripts {
    doLast {
        unixScript.text = unixScript.text.replace('DEFAULT_JVM_OPTS=""', 'DEFAULT_JVM_OPTS="-Dfile.encoding=utf-8"')
    }
}

You may want to do something similar for windowsScript.