Collections - Java Quiz Question

Creating CopyOnWriteArrayList and Iterator

Creating DelayQueue And Iterator for it Next-but

What will be the output of the following program?

import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

public class Test {

    public static void main(String[] args) {
        Map<String, String> myMap = new ConcurrentHashMap<String, String>();
        myMap.put("1", "1");
        myMap.put("2", "1");
        myMap.put("3", "1");
        myMap.put("4", "1");
        myMap.put("5", "1");
        myMap.put("6", "1");
        Iterator<String> it = myMap.keySet().iterator();
        while (it.hasNext()) { 
            String key = it.next();
            if (key.equals("3"))
                myMap.put(key + "new", "new3");
        }
        System.out.println("after iterator: " + myMap);
        myMap = new HashMap<String, String>();
        myMap.put("1", "1");
        myMap.put("2", "1");
        myMap.put("3", "1");
        myMap.put("4", "1");
        myMap.put("5", "1");
        myMap.put("6", "1");
        Iterator<String> it1 = myMap.keySet().iterator();
        while (it1.hasNext()) { 
            String key = it1.next();
            if (key.equals("3")) {
                myMap.put(key + "new", "new3");
                break;
            }
        }
        System.out.println("Hash Map after iterator: " + myMap);
    }
}

	after iterator: {1=1, 3new=new3, 5=1, 6=1, 3=1, 4=1, 2=1} Hash Map after iterator: {3=1, 2=1, 1=1, 3new=new3, 6=1, 5=1, 4=1}
	after iterator: {1=1, 3new=new3, 5=1, 6=1, 3=1, 4=1, 2=1} Hash Map after iterator: {3=1, 2=1, 1=1, new=3new, 6=1, 5=1, 4=1}
	Some other output
	Output can not be determined
	Compilation Error or Runtime Error

Topic: Other Advanced Topics In Java

Read this topic
Take test on this topic

1	Strings and Locales
2	Given the payment details create the SWIFT Message
3	Calculate the EMI Equal Monthly Installment
4	Given the entity object create table query for MySQL
5	Given the object entity create table query for Oracle
6	Given the entity object create the select query for Oracle
7	Create the insert statement for oracle
8	Create the update query for Oracle
9	Convert Object To String
10	Create Getters and Setters Method Signatures
11	AccessVariables test
12	Get the intersection areas between two lines
13	DecimalFormat
14	AWT layout
15	DataBase
16	Format object
17	String Formats
18	Break Iterator Variables And Methods
19	Creating CopyOnWriteArrayList and Iterator
20	Collections
21	Creating DelayQueue And Iterator for it
22	Creating LinkedBlockingDeque and Iterator for it
23	Creating DecimalFormat
24	Threads1706
25	Classes Implementing Runnable Interface
26	Threads1721
27	Creating AWT point
28	Creating AWT Components
29	Collections1768
30	Program with BreakIterator
31	Program with NumberFormat
32	Number Format
33	Buffers
34	Buffers1934
35	Threads1946
36	Garbage Collection
37	Print Distance between two points
38	Assert
39	Find Unique Names
40	Find Unique Names2512
41	Find Unique Names2513
42	Annotation