Does java really allows Pointers ?? why can't it ? ?

Hi Guys,

I need response from all the Java experts. After reading this topic you will come to  a conclusion that java supports Pointers Arithmetic. Actually java 1.5 supports java Pointer Arithmetic. JDK 1.5 has the most disastrous java class called sun.misc.Unsafe which allow you to access the direct memory.
Please execute the following Code and your JVM will get crashed.

Please hang on a minute if java does not support  pointers it should throw Null Reference Exception. but JVM always throw Null Pointer Exception.

Think ..... Think ...... Think....... Think  ....Think..... Think........ and enjoy the below code...

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;
     }
   }



resource:
http://knol.google.com/k/pointers-in-java#

http://www.docjar.com/docs/api/sun/misc/Unsafe.html

Actually it s a bug in jdk 1.5  please read the following link


http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4420961

Java Script Variable Number of arguments

Hi Guys,
As we know we can have the advantage of the  var args(variable number of arguments or variable length arguments ) in Java. Same as in java we have the advantages of var args in java script also.To achieve the variable number of arguments we have a key word called arguments which works only inside of the java script functions.

A pseudo code for that is as follows
----------------------------------------------- 

function test() {
alert(arguments.length);
for(var i=0;i< arguments.length; i++){
alert(arguments[i]);
}
}

and the method call would be

test('13',15,'15');

test('13',15);

test('13');



Please follow the link....

http://www.jtricks.com/javascript_tutorials/varargs.html