Java Collection Program Test-4

import java.util.Collections;

public class Test {

public static void main(String[] args) {

Object[] obj = { new Double(34.56), new String("java"), new Boolean(false), new Integer(87) };

Collections.reverseOrder();

for (int i = 0; i < obj.length; i++) {

System.out.print(obj[i].toString());

}

}

}

import java.util.ArrayList;

import java.util.Collections;

import java.util.Iterator;

import java.util.List;

public class Test {

public static Iterator hello(List list) {

Collections.reverse(list);

return list.iterator();

}

public static void main(String[] args) {

List list = new ArrayList();

list.add("2");

list.add("4");

list.add("6");

Iterator itr = hello(list);

for (Object obj : itr) {

System.out.print(obj + ",");

}

}

}

import java.util.Collection;

import java.util.LinkedList;

public class Test {

public static Collection hello() {

Collection list = new LinkedList();

list.add("A");

list.add("M");

list.add("H");

return list;

}

public static void main(String[] args) {

for (Object obj : hello()) {

System.out.print(obj + ",");

}

}

}

import java.util.LinkedHashSet;

import java.util.Set;

public class Test {

public static void main(String[] args) {

Set set = new LinkedHashSet();

set.add(2);

set.add(4);

System.out.println(set);

}

}

import java.util.PriorityQueue;

public class Test {

public static void main(String[] args) {

PriorityQueue pq = new PriorityQueue();

pq.add("Java");

pq.add("Spring");

pq.add("Hibernate");

System.out.println(pq.element() + "," + pq.peek());

}

}