Java Collections Framework
practice.

Which of these class is used for creating a client for a server-client operations?

What will be the output of the following Java program?

import java.util.*;
class Array
{
    public static void main(String args[]) 
    {
        int array[] = new int [5];
        for (int i = 5; i > 0; i--)
            array[5 - i] = i;
        Arrays.sort(array);
        for (int i = 0; i < 5; ++i)
          System.out.print(array[i]);;
    }
}

What is the unique feature of LinkedHashSet?

What will be the output of the following Java program?

import java.util.*;
class Arraylist 
{
    public static void main(String args[])
    {
        ArrayList obj1 = new ArrayList();
        ArrayList obj2 = new ArrayList();
        obj1.add("A");
        obj1.add("B");
        obj2.add("A");
        obj2.add(1, "B");
        System.out.println(obj1.equals(obj2));
    }
}

What will be the output of the following Java program?

import java.util.*;
class Maps 
{
    public static void main(String args[]) 
    {
        HashMap obj = new HashMap();
        obj.put("A", new Integer(1));
        obj.put("B", new Integer(2));
        obj.put("C", new Integer(3));
        System.out.println(obj);
    }
}

Which of these class object uses the key to store value?

Which of these class object can be used to form a dynamic array?

What will be the output of the following Java program?

import java.util.*;
class Collection_Algos 
{
    public static void main(String args[]) 
    {
        LinkedList list = new LinkedList();
        list.add(new Integer(2));
        list.add(new Integer(8));
        list.add(new Integer(5));
        list.add(new Integer(1));
        Iterator i = list.iterator();
        Collections.reverse(list);
  while(i.hasNext())
      System.out.print(i.next() + " ");
    }
}

What will be the output of the following Java code?

import java.util.*;
class vector 
{
    public static void main(String args[]) 
    {
        Vector obj = new Vector(4,2);
        obj.addElement(new Integer(3));
        obj.addElement(new Integer(2));
        obj.addElement(new Integer(5));
        System.out.println(obj.elementAt(1));
    }
}

What will be the output of the following Java code?

import java.util.*;
class stack 
{
    public static void main(String args[]) 
    {
        Stack obj = new Stack();
        obj.push(new Integer(3));
        obj.push(new Integer(2));
        obj.pop();
        obj.push(new Integer(5));
      System.out.println(obj);
    }
}

Which of these methods can randomize all elements in a list?

If two threads access the same hashmap at the same time, what would happen?

Which of these methods can be used to obtain a static array from an ArrayList object?

Which of these method is used to insert value and its key?

Which of these method is used to remove all keys/values pair from the invoking map?

What will be the output of the following Java program?

import java.util.*;
class Collection_iterators 
{
    public static void main(String args[]) 
    {
        ListIterator a = list.listIterator();
            if(a.previousIndex()! = -1)
                while(a.hasNext())
              System.out.print(a.next() + " ");
            else
               System.out.print("EMPTY");
    }
}

What will be the output of the following Java program?

import java.lang.reflect.*;
class Additional_packages
{	 
     public static void main(String args[])
     {
   try
         {
       Class c = Class.forName("java.awt.Dimension");
 Method methods[] = c.getMethods();
 for (int i = 0; i < methods.length; i++)
     System.out.println(methods[i]);
   }
   catch (Exception e)
         {
         System.out.print("Exception");
         }
    }
}

What happens if we put a key object in a HashMap which exists?

Which of these interface handle sequences?

How to externally synchronize hashmap?