Proc in Java

DomainClass.java

package main;

public class DomainClass {
	public void doSomething(Object arg0, Proc block) {
		// do something
		block.run(arg0);
	}
}

Main.java

package main;

public class Main {
	public static void main(String[] args) {
		DomainClass mc = new DomainClass();
		mc.doSomething("some argument", new Proc() {
			public Object run(Object ... args) {
				System.out.println("Proc with: " + args[0]);
				return null;
			}
		});
	}
}

Proc.java

package main;

public interface Proc {
	public Object run(Object ... args);
}

Is this the best way to simulate Procs in Java?

I believe so, this is probably the closest you can get from Ruby Procs in Java, sadly.