Checking whether String is an interface or class : Interface « Reflection « Java Tutorial

public class Main {
  public static void main(String[] argv) throws Exception {

    Class clazz = String.class;
    boolean isInterface = clazz.isInterface();
    System.out.println("Is Interface = " + isInterface);

7.2.1.The superclass of interfaces is always null
7.2.2.Listing the Interfaces That an Interface Extends
7.2.3.Checking whether String is an interface or class
7.2.4.If a class object is an interface or a class
7.2.5.Listing the Interfaces That a Class Implements
7.2.6.Although the type of o2 is an interface, getSuperclass() returns the object's superclass
7.2.7.The interfaces for a primitive type is an empty array
7.2.8.Return Returns true if type is implementing Map
7.2.9.Returns true if a class implements Serializable and false otherwise.
7.2.10.Get Super Interfaces
7.2.11.Get all interface and object classes that are generalizations of the provided class