TestPointers.java

import sun.misc.Unsafe;
import java.lang.reflect.Field;

public class TestPointers {
    public static void main(String[] args) throws Exception {
         Unsafe unsafe = getUnsafe();
         System.out.println("Unsafe = " + unsafe);
         System.out.println(" addressSize() = " + unsafe.addressSize());
         System.out.println(" pageSize() = " + unsafe.pageSize());
         System.out.println(" pageSize() = " + unsafe.pageSize());
         try {
             unsafe.putByte((long) 0xa000, (byte) 47);
         } catch(Throwable e) {
             System.out.println("IN THE CATCH BLOCK");
             e.printStackTrace();
         } finally {
             System.out.println("IN THE FINALLY BLOCK");
         }
         System.exit(0);
    }

     public static Unsafe getUnsafe() {
         Unsafe unsafe = null;
         try {
             Class uc = Unsafe.class;
             Field[] fields = uc.getDeclaredFields();
             for(int i = 0; i < fields.length; i++) {
                 if(fields[i].getName().equals("theUnsafe")) {
                     fields[i].setAccessible(true);
                     unsafe = (Unsafe) fields[i].get(uc);
                     break;
                 }
             }
         } catch(Exception ignore) {
     }
     return unsafe;
     }
   }