How to execute selective methods from a group using Beanshell in TestNG

GroupTest.java

package org.rationale.emotions;

import org.testng.annotations.Test;

public class GroupTest {
    @Test(groups = "dragon-lord")
    public void foo() {
        System.err.println("foo() says hello");
    }

    @Test(groups = "dragon-lord")
    public void bar() {
        System.err.println("bar() says hello");
    }

    @Test(groups = "dragon-lord")
    public void foobar() {
        System.err.println("foobar() says hello");
    }
}

selective-groups.xml

<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd" >
<suite name="My Suite" verbose="1" parallel="false" thread-count="1">
    <test name="groups-demo">
        <method-selectors>
            <method-selector>
                <script language="beanshell">
                    <![CDATA[
                    whatGroup = System.getProperty("whatgroup","dragon-lord");
                    whatMethod = System.getProperty("methodToRun", "foo");
                    if (whatGroup.isEmpty() || whatMethod.isEmpty()) {
                         return true;
                    }
                    return groups.containsKey(whatGroup) && method.getName().equals(whatMethod);
                    ]]>
                </script>
            </method-selector>
        </method-selectors>
        <classes>
            <class name="org.rationale.emotions.GroupTest"/>
        </classes>
    </test>

</suite>