/* standard HelloWorld.java program */
class HelloWorld
{
	public static void main(String[] args)
	{
		System.out.println("Hello, World!!!");
	}
}

genjix@linux:~/media/programming/java> gcj HelloWorld.java
/usr/lib/gcc-lib/i586-suse-linux/3.3.4/../../../crt1.o(.text+0x18): In function`_start':
../sysdeps/i386/elf/start.S:115: undefined reference to `main'
collect2: ld returned 1 exit status
genjix@linux:~/media/programming/java>

Quote:Original post by nmi
make the class public

You also need to specify the --main option:
http://gcc.gnu.org/onlinedocs/gcj/Linking.html#Linking

Read here:
http://www.linuxjournal.com/article/4860