Playing around with generating class hierarchies.

ClassHierarchyGenerator.java

package classhierarchy;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.Set;

public class ClassHierarchyGenerator {

    public static void main(String... args) {
        Class<?> c = ArrayList.class;

        System.out.println(getClassHierarchy(c));
    }

    public static Set<Class<?>> getClassHierarchy(Class<?> clazz) {
        Set<Class<?>> classHierarchy = new HashSet<>();

        Class<?> superclass = clazz.getSuperclass();

        if (classHierarchy.contains(superclass) || superclass == null) {
            return classHierarchy;
        }

        classHierarchy.add(superclass);
        classHierarchy.addAll(getClassHierarchy(superclass));

        for (Class currentInterface : clazz.getInterfaces()) {
            classHierarchy.add(currentInterface);
            classHierarchy.addAll(getClassHierarchy(currentInterface));
        }

        return classHierarchy;
    }
}