Java Test 5 - 2024

Q1. Given that a class named mywids.Widget is part of a module named mod.wids packaged in mywidgets.jar, which of the following commands can be used to execute this class?

(Assume that the jar file is located in the current directory and the jar file does not have any entry in its manifest.)

You had to select 1 option(s)

Q2. Given the following code:

sealed interface Cacheable permits Value, Result{
default void clear(){ System.out.println("clearing cache..."); }
}

Which of the following definitions will compile without error?

You had to select 2 option(s)

Q3. Given the following code, which method declarations can be inserted at line 1 without any problems?

public class OverloadTest{
public int sum(int i1, int i2) { return i1 + i2; }
// 1
}

You had to select 3 option(s)

Q4. Given that a file named test1.txt contains the following data:

01234567
and the following code snippet:

char[] buf = new char[5];
try( FileReader fr = new FileReader("c:\\temp\\test1.txt");
FileWriter fw = new FileWriter("c:\\temp\\test2.txt")){

while( fr.read(buf) != -1){
fw.write(buf);
}
}

What will be the contents of test2.txt after the above code is run?

You had to select 1 option(s)

Q5. Given :

TEACHER table in the database with the following data:

TID(int) NAME(varchar) SUBJECT(varchar)
--------------------
1 Ally MATH
2 Bob MATH
1 Ally SCIENCE

and the following code:

try(
Connection c = ds.getConnection(); //assume that ds refers to a DataSource
PreparedStatement selectPS
= c.prepareStatement("select TID, SUBJECT from TEACHER where NAME = ?");
PreparedStatement insertPS
= c.prepareStatement("insert into TEACHER(NAME, TID) VALUES (?, ?)");
)
{
selectPS.setString(1, "Ally");
ResultSet rs = selectPS.executeQuery();
while(rs.next()){
insertPS.setObject(1, rs.getObject(2), JDBCType.VARCHAR);
insertPS.setObject(2, rs.getObject(1), JDBCType.INTEGER);
insertPS.execute(); //1
}
}

Assuming that a SUBJECT table with no rows also exists, identify correct statements.

You had to select 2 option(s)

Q6. What will the following code fragment print?

Path p1 = Paths.get("c:\\..\\temp\\test.txt");
System.out.println(p1.normalize().toUri());

You had to select 1 option(s)

Q7. Given:

static boolean validateInput(String str){
return INSERT CODE HERE;
}

Which of the following expressions can be inserted in the above code so that the validateInput method will return true if and only if the input string contains non-whitespace data?

You had to select 1 option(s)

Q8. Given:

public class ThreadSafety{
List sList = new ArrayList();

public Student getStudent(){
var s = sList.remove(0);
return s;
}
...other irrelevant code
}
If two threads, T1 and T2, concurrently execute getStudent() method on the same ThreadSafety instance, which of the following are possible outcomes? (Assume that there are no nulls in the list.)

You had to select 3 option(s)

Q9. Your application uses one modular jar (a.jar), which, in turn, uses one non-modular jar (b.jar). Which of the following commands will cause jdeps to include the non-modular jar in its analysis?

You had to select 1 option(s)

Q10. Which of the following are valid ways to create a LocalDateTime?

You had to select 1 option(s)

Q11. Given:

var books = new ArrayList(List.of(new Book("The Outsider", "Stephen King"),
new Book("Becoming", "Michelle Obama" ), new Book("Uri", "India")));
Stream bkStrm = books.stream(); //1
int count = bkStrm.peek(x->x.getTitle()).count();//2

Assuming that the Book class has appropriate constructor and method, what changes can be made to the above code independent of each other to make it will compile ?

You had to select 1 option(s)

Q12. Given the following line of code:

LocalDateTime dt = LocalDateTime.parse("2022-01-02T17:13:50");

Which of the following lines will return the date string in ISO 8601 format?

You had to select 2 option(s)

Q13. What will the following code print when run?

Period p = Period.between(LocalDate.now(), LocalDate.of(2022, Month.SEPTEMBER, 1));
System.out.println(p);

Duration d = Duration.between(LocalDateTime.now(),
LocalDateTime.of(2022, Month.SEPTEMBER, 2, 10, 10));

System.out.println(d);

Assume that the local time on the system at the time this code is run is 2nd Sep 2022 1:00 AM.

You had to select 1 option(s)

Q14. Given:

public class TestClass{

static int someMethod(){ return 100; }

static class MyWorker{
Runnable r;
public MyWorker(Runnable r){
this.r = r;
}
}
public static void main(String[] args) {
//INSERT CODE HERE
MyWorker w = new MyWorker(r);
}
}

What can be inserted in the above code?

You had to select 3 option(s)

Q15. Given the following code (assume appropriate imports):

public class IOTest {
public static void main(String[] args) {
var myfile = Paths.get("test.txt");
try(var bfr = Files.newBufferedReader(myfile, Charset.forName("US-ASCII") )){
String line = null;
while( (line = bfr.readLine()) != null){
System.out.println(line);
}
}catch(Exception e){
System.out.println(e);
}
}
}

What will be printed when this code is run if test.txt doesn't exist?

You had to select 1 option(s)

Q16. What will be the output if you run the following program?

public class TestClass{
public static void main(String args[]){
int i;
int j;
for (i = 0, j = 0 ; j < 1 ; ++j , i++){
System.out.println( i + " " + j );
}
System.out.println( i + " " + j );
}
}

You had to select 1 option(s)

Q17. Given the following code snippet:

int rate = 10;
int t = 5;
XXX amount = 1000.0;
for(int i=0; i<t; i++){
amount = amount*(1 - rate/100);
}

What can XXX be?

You had to select 1 option(s)

Q18. Consider the following code appearing in a file named TestClass.java:

class Test{ } // 1

public class TestClass {

var v1; // 2

public int main(String[] args) { // 3

var v2; //4

double x=10, double y; // 5

System.out.println[]; // 6

for(var k=0; k<x; k++){ } //7

return 0;
}
}

Which of the lines are valid?

You had to select 3 option(s)

Q19. What will the following code fragment print?

Path p1 = Paths.get("photos\\..\\beaches\\.\\calangute\\a.txt");
Path p2 = p1.normalize();
Path p3 = p1.relativize(p2);
Path p4 = p2.relativize(p1);

System.out.println(
p1.getNameCount()+" "+p2.getNameCount()+" "+
p3.getNameCount()+" "+p4.getNameCount());

You had to select 1 option(s)

Q20. Which of the following are valid declarations inside the FooI interface?

interface AI{
void moo();
}
interface FooI extends AI{
//INSERT CODE HERE
}

You had to select 2 option(s)

Q21. Which of the following statements will compile without any error?

You had to select 4 option(s)

Q22. Consider the following classes...

class Car{
public int gearRatio = 8;
public String accelerate() { return "Accelerate : Car"; }
}
class SportsCar extends Car{
public int gearRatio = 9;
public String accelerate() { return "Accelerate : SportsCar"; }
public static void main(String[] args){
Car c = new SportsCar();
System.out.println( c.gearRatio+" "+c.accelerate() );
}
}

What will be printed when SportsCar is run?

You had to select 1 option(s)

Q23. Which of the following methods can be called on a String object?

You had to select 4 option(s)

Q24. Given:

import java.time.LocalDate;
import static java.time.DayOfWeek.*;
public class TestClass {
public static void main(String[] args){
var day = LocalDate.now().with(FRIDAY).getDayOfWeek();

switch(day){
case MONDAY:
TUESDAY:
WEDNESDAY:
THURSDAY:
FRIDAY:
System.out.println("working");
case SATURDAY:
SUNDAY:
System.out.println("off");
}
}
}

What is the output?

You had to select 1 option(s)

Q25. Which line(s) in the following code will fail compilation?

interface Tool{ //1
void operate(); //2
}

abstract class PowerTool implements Tool{ } //3

class PowerSaw implements PowerTool{ //4
@Override //5
public void operate(){ }
}

class SteamPowerSaw extends PowerSaw{ //6
@Override //7
public void operate(int pressure){ }
}

You had to select 2 option(s)

Q26. Your application includes a method that generates a report using Employee data. While generating the report, if this method detects inconsistent payment records, it cannot generate the report. You want to create a new exception class that should be thrown in this situation. Which of the following is the best implementation for this exception?

You had to select 1 option(s)

Q27. Which of the following code snippets appearing in a method are valid?

You had to select 1 option(s)

Q28. Given:

class MyException extends Exception {
private final int code;
public MyException(int code, Throwable actualEx){
super(actualEx);
this.code = code;
}

public MyException(int code, String message, Throwable actualEx){
super(message, actualEx);//1
this.code = code;
}

public String getMessage(){
return String.format("Exception - Code=%d, Msg=%s, OrigMsg=%s",
code, super.getMessage(), this.getCause().getMessage()); //2
}
}

public class TestClass {
public static void main(String[] args) {
try{
throw new MyException(404, "NOT FOUND",
new IOException("FILE UNREADABLE")); //3
}catch(Exception e){
System.out.println(e.getMessage());
}
}
}

What is the result?

You had to select 1 option(s)

Q29. Given:

var bfr = new BufferedReader(new FileReader("c:\\temp\\pathtest\\a.java"));
var bfw = new BufferedWriter(new FileWriter("c:\\temp\\pathtest\\b.java"));
String line = null;
while( (line=bfr.readLine()) != null ){
bfw.append(line);
}

//INSERT CODE HERE

bfw.close();


Which of the following lines is required to be inserted in the code above so that content in b.java will be overwritten with the content in a.java?

You had to select 1 option(s)

Q30. What will be printed when the following program is compiled and run?

class Super{
public int getNumber( int a){
return 2;
}
}
public class SubClass extends Super{
public int getNumber( int a, char ch){
return 4;
}
public static void main(String[] args){
System.out.println( new SubClass().getNumber(4) );
}
}

What will be printed?

You had to select 1 option(s)

Q31. Which is the first line that will cause compilation to fail in the following program?

// Filename: A.java
class A{
public static void main(String args[]){
A a = new A();
B b = new B();
a = b; // 1
b = a; // 2
a = (B) b; // 3
b = (B) a; // 4
}
}
class B extends A { }

You had to select 1 option(s)

Q32. The following are complete contents of ConsoleTest.java:

import java.io.Console;
public class ConsoleTest {
public static void main(String[] args) {
var c = System.console(); //1
char[] line = c.readPassword("Please enter your pwd:"); //2
System.out.println("Pwd is "+new String(line));
}
}

What will happen when it is compiled and run from the command line?

You had to select 1 option(s)

Q33. Given:

public class Student {
private String name;
private int marks;

//constructor and getters and setters not shown

public void addMarks(int m){
this.marks += m;
}
public void debug(){
System.out.println(name+":"+marks);
}
}

What will the following code print when compiled and run?

List slist = List.of(new Student("S1", 40),
new Student("S2", 35),
new Student("S3", 30));
Consumer increaseMarks = s->s.addMarks(10);
slist.forEach(increaseMarks);
slist.forEach(Student::debug);

You had to select 1 option(s)

Q34. Given:

public static void main(String[] args) {
INSERT CODE HERE
List.of(args).forEach(x);
}
Which of the following options can be inserted in the above code without causing a compilation error?

You had to select 2 option(s)

Q35. Given:

//creating Book objects using Book(String title, String author) constructor
var books = List.of( new Book("Where the Crawdads Sing", "Dalia Owens" ),
new Book("The Outsider", "Stephen King"),
new Book("Elevation", "Stephen King"),
new Book("Coffin from Hong Kong", "James Hadley Chase") );
Stream bkStrm = books.stream();

*INSERT CODE HERE*

Assuming Book class has appropriate constructor and accessor methods, which of the following lines of code will get you the first book written by Stephen King from the list of of books?

You had to select 1 option(s)

Q36. What can be the return type of method getSwitch so that this program compiles and runs without any problems?

public class TestClass{
public static XXX getSwitch(int x){
return x - 20/x + x*x;
}
public static void main(String args[]){
switch( getSwitch(10) ){
case 1 :
case 2 :
case 3 :
default : break;
}
}
}

You had to select 1 option(s)

Q37. Assume that a table named department exists and has the following data:

ID| NAME| CODE
1 | HR| 111


What will the following code print?



You had to select 1 option(s)

Q38. What will be the result of attempting to compile and run the following code?

public class Nesting
{
public static void main(String args[])
{
B.C obj = new B( ).new C( );
}
}
class A
{
char c;
A(char c) { this.c = c; }
}
class B extends A
{
char c = 'a';
B( ) { super('b'); }
class C extends A
{
char c = 'c';
C( )
{
super('d');
System.out.println(B.this.c);
System.out.println(C.this.c);
System.out.println(super.c);
}
}
}

You had to select 1 option(s)

Q39. Which of the following correctly identify the differences between a Callable and a Runnable?

You had to select 3 option(s)

Q40. Given that test1.txt exists but test2.txt doesn't exist, consider the following code?

public class FileCopier {

public static void copy1(Path p1, Path p2) throws Exception {
Files.copy(p1, p2, StandardCopyOption.COPY_ATTRIBUTES);
}


public static void main(String[] args) throws Exception {
Path p1 = Paths.get("c:\\temp\\test1.txt");
Path p2 = Paths.get("c:\\temp\\test2.txt");
copy1(p1, p2);
}
}

Which file attributes will be copied over to test2.txt?

You had to select 1 option(s)

Q41. Consider the following code:

public class Student {
private Map marksObtained
= new HashMap();
private ReadWriteLock lock = new ReentrantReadWriteLock();
public void setMarksInSubject(String subject, Integer marks){
// valid code to set marks for a given subject
}
public double getAverageMarks(){

//1 - INSERT CODE HERE

var sum = 0.0;
try{
for(Integer mark : marksObtained.values()){
sum = sum + mark;
}
return sum/marksObtained.size();
}finally{

//2 - INSERT CODE HERE

}
}
}

What should be inserted at //1 and //2?

You had to select 1 option(s)

Q42. Consider the following code snippet ...

boolean[] b1 = new boolean[2];
boolean[] b2 = {true , false};
System.out.println( "" + (b1[0] == b2[0]) + ", "+ (b1[1] == b2[1]) );

What will it print ?

You had to select 1 option(s)

Q43. Consider the contents of following two files:

//In file A.java
package a;
public class A{
A(){ }
public void print(){ System.out.println("A"); }
}

//In file B.java
package b;
import a.*;
public class B extends A{
B(){ }
public void print(){ System.out.println("B"); }
public static void main(String[] args){
new B();
}
}


What will be printed when you try to compile and run class B?

You had to select 1 option(s)

Q44. Consider the following code fragment:

public static void myMethod(int x) //Specify throws clause here
{
try{
if(x == 0){
throw new ClassNotFoundException();
}
else throw new NoSuchFieldException();
}catch(RuntimeException e){
throw e;
}
}


Which of the following is a valid throws clause for the above method?

You had to select 2 option(s)

Q45. Given that Book is a valid class with appropriate constructor and getTitle and getPrice methods that return a String and a Double respectively, what can be inserted at //1 and //2 so that it will print the price of all the books having a title that starts with "A"?

List books = Arrays.asList(
new Book("Atlas Shrugged", 10.0),
new Book("Freedom at Midnight", 5.0),
new Book("Gone with the wind", 5.0)
);

Map bookMap = //1 INSERT CODE HERE
//2 INSERT CODE HERE
bookMap.forEach(func);

You had to select 1 option(s)

Q46. Given:

Character[] ca = { 'b', 'c', 'a', 'e', 'd' };
List l = Arrays.asList(ca);
l.parallelStream().peek(System.out::print).forEachOrdered(System.out::print);

Identify the correct statement about the above code.

You had to select 1 option(s)

Q47. Which of the following statements are correct regarding the module system of Java.

You had to select 3 option(s)

Q48. Which of the following are valid implementations of java.lang.Comparable?

You had to select 1 option(s)

Q49. Given:

import java.util.*;
public class EventProcessor{
public void processEvents(Collection c){
c.forEach(o -> System.out.println(o));
}
}

class MapEventProcessor extends EventProcessor{
public void processEvents(Map events){
*INSERT CODE HERE*
}
}

Which of the following options can be inserted in the above code without compilation error?

You had to select 2 option(s)

Q50. Given the following set of member declarations, which of the following is true?

int a; // (1)
static int a; // (2)
int f( ) { return a; } // (3)
static int f( ) { return a; } // (4)

You had to select 2 option(s)

Q51. Consider the following class...

public class ParamTest {

public static void printSum(int a, int b){
System.out.println("In int "+(a+b));
}

public static void printSum(double... a){
System.out.println("In double "+(a[0]+a[1]) );
}
public static void printSum(float a, float b){
System.out.println("In float "+(a+b));
}
public static void printSum(int a, float b){
System.out.println("In intfloat "+(a+b));
}
public static void main(String[] args) {
printSum(1, 2.0);
}
}

What will be printed?

You had to select 1 option(s)

Q52. What will the following code print when compiled and run?

class Test{
public static void main(String args[]){
int c = 0;
A: for(var i = 0; i < 2; i++){
B: for(var j = 0; j < 2; j++){
C: for(var k = 0; k < 3; k++){
c++;
if(k>j) break;
}
}
}
System.out.println(c);
}
}

You had to select 1 option(s)

Q53. Consider the following method which is called with an argument of 7, d, where d is some double value:

Q54. java.util.Locale allows you to do which of the following?

You had to select 2 option(s)

Q55. Which of the following commands can be used to identify class and module dependencies?

You had to select 1 option(s)