Type[] genericInterfaces = Document.class.getGenericInterfaces();
        for (var type : genericInterfaces) {
            if (type instanceof ParameterizedType parameterizedType) {
                System.out.println(parameterizedType.getRawType().getTypeName());
                for (var typeArguments : parameterizedType.getActualTypeArguments()) {
                    System.out.println("   " + typeArguments.getTypeName());
                }
            }
        }
prints:

java.util.Map
   java.lang.String
   java.lang.Object