If you have easy access the bytecode, the program `javap' can print out
the signature for the method (foo(II)V).

Barring that, it is pretty easy to transform a
java.lang.reflect.Method's toString() to a JVM internal String.

I believe that this information is not available in the standard Java
API. Haven't followed late changes though..

To get this info, I'm using the Apache BCEL library
(http://jakarta.apache.org/bcel/):

$ cat SignatureLister.java
import java.io.*;

import org.apache.bcel.*;
import org.apache.bcel.classfile.*;
import org.apache.bcel.generic.*;
import org.apache.bcel.util.*;

public class SignatureLister {
   public static void main(String args[]) throws IOException {
       ClassParser parser  = new ClassParser(args[0]);
       JavaClass   clazz   = parser.parse();
       Method[]    methods = clazz.getMethods();

       for(int i=0; i<methods.length; i++) {
           System.out.print(clazz.getClassName());
           System.out.print(".");
           System.out.print(methods[i].getName());
           System.out.println(methods[i].getSignature());
       }    
   }
}

$ javac -classpath bcel-5.2.jar SignatureLister.java

$ $ java -cp bcel-5.2.jar:. SignatureLister A.class
A.<init>()V
A.foo(II)V

br,
Pietu