Obtain instances of java.lang.Class in Java

/* w w w  . ja  v a  2 s  .c  o m*/
public class Main {
  /** An Integer object */
  protected static Integer someInteger = new Integer(10);

  /** A generic object. */
  protected static Object someObject = null;

  /** A String. */
  protected static String someString = new String("Hardcore Java");

  /** An int. */
  protected static int someInt = 15;

  /** An array of ints. */
  protected static int[] intArray = new int[] { 4, 5, 7, 9 };

  public static void main(final String[] args) {
    // -- Print out the Class instances. 
    System.out.println(someInteger.getClass());
    System.out.println(someString.getClass());
    System.out.println(intArray.getClass());
    System.out.println(Object.class);
    System.out.println(Integer.class);
    System.out.println(int.class);
    System.out.println(String.class);
    System.out.println(Comparable.class);
    System.out.println(Object[].class);

    // -- Things that WON'T work
    // System.out.println(someObject.getClass());  // <= Exception 
    // System.out.println(someInt.getClass()); // <= Compiler errror
  }
  public void writeClass(final Object obj) {
    System.out.println(obj.getClass());
  }
}