find all classes and interfaces a class extends or implements recursively

Question

I was wondering if there was an easy way of determining the complete list of Types that a Java class extends or implements recursively?

for instance:

cla         


        

Answer 1

The key you want is in the Class#getSuperclass() method:

public static Set> stuff(Class target) {
    Set> classesInterfaces = new HashSet<>();
    classesInterfaces.add(target);
    classesInterfaces.addAll(Arrays.asList(target.getInterfaces());

    Class superClass = target.getSuperclass();
    if(superClass != null)
        classesInterfaces.addAll(stuff(superClass));
}