Certified Java Programmer Mock Exam

Question 1

Which implementation of the List interface produces the slowest access to an element in the middle of the list by means of an index?

Question 2

import java.util.*;
class GFC100 {
  public static void main (String args[]) {
    Object a1 = new LinkedList(), b1 = new TreeSet();
    Object c1 = new TreeMap();
    System.out.print((a1 instanceof Collection)+",");
    System.out.print((b1 instanceof Collection)+",");
    System.out.print(c1 instanceof Collection);
}}

What is the result of attempting to compile and run the program?

Question 3

Which of these classes provides the specified features?

Question 4

import java.util.*;
class GFC101 {
  public static void main (String args[]) {
    Object a1 = new HashMap(), b1 = new ArrayList();
    Object c1 = new HashSet();
    System.out.print((a1 instanceof Collection)+",");
    System.out.print((b1 instanceof Collection)+",");
    System.out.print(c1 instanceof Collection);
}}

What is the result of attempting to compile and run the program?

Question 5

Which interface of the java.util package offers the specified behavior?

Question 6

import java.util.*;
class GFC102 {
  public static void main (String args[]) {
    Object a = new HashSet();
    System.out.print((a instanceof Set)+",");
    System.out.print(a instanceof SortedSet);
}}

What is the result of attempting to compile and run the program?

Question 7

Which implementation of the List interface provides for the fastest insertion of a new element into the middle of the list?

Question 8

import java.util.*;
class GFC103 {
  public static void main (String args[]) {
    Object a1 = new TreeSet();
    System.out.print((a1 instanceof Set)+",");
    System.out.print(a1 instanceof SortedSet);
}}

What is the result of attempting to compile and run the program?

Question 9

Which of these classes provides the specified features?

Question 10

import java.util.*;
class GFC104 {
  public static void main (String args[]) {
    LinkedList a1 = new LinkedList();
    ArrayList b1 = new ArrayList();
    Vector c1 = new Vector();
    System.out.print((a1 instanceof List)+",");
    System.out.print((b1 instanceof List)+",");
    System.out.print(c1 instanceof List);
}}

What is the result of attempting to compile and run the program?

Question 11

Which interface of the java.util package offers the specified behavior?

Question 12

import java.util.*;
class GFC105 {
  public static void main (String args[]) {
    Object a = new HashSet(), b = new HashMap();
    Object c = new Hashtable();
    System.out.print((a instanceof Collection)+",");
    System.out.print((b instanceof Collection)+",");
    System.out.print(c instanceof Collection);
}}

What is the result of attempting to compile and run the program?

Question 13

Which of these classes provides the specified features?

Question 14

import java.util.*;
class GFC106 {
  public static void main (String args[]) {
    Object a = new HashSet(), b = new HashMap();
    Object c = new Hashtable();
    System.out.print((a instanceof Map)+",");
    System.out.print((b instanceof Map)+",");
    System.out.print(c instanceof Map);
}}

What is the result of attempting to compile and run the program?

Question 15

Which of these classes provides the specified features?

Question 16

import java.util.*;
class GFC107 {
  public static void main (String args[]) {
    Object a = new HashSet(), b = new HashMap();
    Object c = new Hashtable();
    System.out.print((a instanceof Cloneable)+",");
    System.out.print((b instanceof Cloneable)+",");
    System.out.print(c instanceof Cloneable);
}}

What is the result of attempting to compile and run the program?

Question 17

Which interface of the java.util package offers the specified behavior?

Question 18

import java.util.*;
import java.io.Serializable;
class GFC108 {
  public static void main (String args[]) {
    HashMap a = new HashMap();
    boolean b1, b2, b3;
    b1 = (a instanceof Cloneable) & (a instanceof Serializable);
    b2 = a instanceof Map;
    b3 = a instanceof Collection;
    System.out.print(b1 + "," + b2 + "," + b3);
}}

What is the result of attempting to compile and run the program?

Question 19

Which of the following classes allow unsynchronized read operations by multiple threads?

Question 20

Which interface of the java.util package offers the specified behavior?

Question 21

import java.util.*;
class GFC110 {
  public static void main (String[] args) {
    Object m = new LinkedHashMap();
    System.out.print((m instanceof Collection)+",");
    System.out.print((m instanceof Map)+",");
    System.out.print(m instanceof List);
}}

What is the result of attempting to compile and run the program?

Question 22

import java.util.*;
class GFC109 {
  public static void main (String[] args) {
    Object v = new Vector();
    System.out.print((v instanceof Collections)+",");
    System.out.print((v instanceof Arrays)+",");
    System.out.print(v instanceof List);
}}

What is the result of attempting to compile and run the program?