Java Standard Test 6 – 2025

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Welcome to your Standard Test 6 - 2025

Name

Phone

Q1. What will the following program print?

public class TestClass{
public static void main(String[] args){
var str = "111";
boolean[] bA = new boolean[1];
if( bA[0] ) str = "222";
System.out.println(str);
}
}

Select 1 option(s):

111

222

It will not compile as bA[0] is uninitialized.

It will throw an exception at runtime.

None of the above.

None

Q2. What will the following code print?

int i1 = 1, i2 = 2, i3 = 3;
float i4 = i1 + (i2=i3 );
System.out.println((int)i4);

Select 1 option(s):

4.0

4.0f

It will not compile.

None

Q3. Which of the given option when inserted in the code below will make the code print true?

List values = Arrays.asList("Alpha A", "Alpha B", "Alpha C");
//INSERT CODE HERE
System.out.println(flag);

Select 1 option(s):

boolean flag = values.stream().allMatch(str->str.equals("Alpha"));

boolean flag = values.stream().findFirst().get().equals("Alpha");

boolean flag = values.stream().findAny().get().equals("Alpha");

boolean flag = values.stream().anyMatch(str->str.equals("Alpha"));

None of the above.

None

Q4. When is the Object created at line //1 eligible for garbage collection?

public class TestClass{
public Object getObject(){
Object obj = new String("aaaaa"); //1
Object objArr[] = new Object[1]; //2
objArr[0] = obj; //3
obj = null; //4
objArr[0] = null;//5
return obj; //6
}
}

Select 1 option(s):

Just after line 2.

Just after line 3.

Just after line 4.

Just after line 5.

Just after line 6.

None

Q5. Given the following code:

interface Device {
public abstract void switchOn();
}

abstract class Router /* LOCATION 1 */ {
/* LOCATION 2 */
public void switchOn(){ }

public abstract void reset();
}

class MimoRouter extends Router implements Device{
/* LOCATION 3 */
}

Which code, when inserted at one or more marked locations, would allow classes Router and MimoRouter to compile?

(Consider each option as independent of other options.)

Select 2 option(s):

implements Device //at location 1
@Override //at location 2

public void reset(){ } //at location 3

@Override //at location 2
public void reset() { } //at location 3

@Override //at location 3
void switchOn(){ } //at location 3
@Override //at location 3
public void reset(){ }//at location 3

@Override //at location 2 and 3
public void switchOn(){ } //at location 2 and 3
public void reset(){ }//at location 3

implements Device //at location 1
@Override //at location 2
public void reset(){ }//at location 3

Q6. Consider the following code:

class MyClass { }
public class TestClass{
MyClass getMyClassObject(){
MyClass mc = new MyClass(); //1
return mc; //2
}
public static void main(String[] args){
TestClass tc = new TestClass(); //3
MyClass x = tc.getMyClassObject(); //4
System.out.println("got myclass object"); //5
x = new MyClass(); //6
System.out.println("done"); //7
}
}

After what line the MyClass object created at line 1 will be eligible for garbage collection?

Select 1 option(s):

Never till the program ends.

None

Q7. Given the following code:

public void someMethod(){
var values = new ArrayList();
//INSERT CODE HERE
}

What can be inserted at the given location without causing any compilation error?

Select 2 option(s):

values.sort( var a, var b -> a.compareTo(b) );

values.sort( (a, b) -> a.compareTo(b) );
values.forEach( System.out::println );

values.sort();
values.forEach( System.out::println);

values.removeIf((var k)->k.equals("a") );

String[] sa = values.toArray();

class Local{
var value = 10;
}

Q8. Your application is packaged in myapp.jar and depends on a jar named datalayer.jar, which in turn depends on mysql-connector-java-8.0.11.jar. The following packages exist in these jars:

myapp.jar: com.abc.myapp
datalayer.jar: com.abc.datalayer
mysql-connector-java-8.0.11.jar: com.mysql.jdbc

You have decided to modularize your application even though datalayer and mysql libraries are still not modularlized. Which of the following would be a valid module-info for your app?

Select 1 option(s):

module abc.myapp{
requires com.abc.datalayer;
}

module abc.myapp{
exports com.abc.myapp;
}

module abc.myapp{
requires datalayer;
}

module abc.myapp{
requires datalayer;
requires mysql-connector-java;
}

module abc.myapp{
requires datalayer;
requires mysql-connector-java-0.0.11;
}

module abc.myapp{
requires com.abc.datalayer;
requires com.mysql.jdbc;
}

None

Q9. Given:

enum Card
{
HEART, CLUB, SPADE, DIAMOND;

public boolean isRed(){
return switch(this){
case HEART, DIAMOND -> true;
default -> false;
};
}
}

What will the following code print?

Arrays.stream(Card.values()).dropWhile(c->c.isRed());
switch(Card.valueOf("HEART")){
case HEART -> System.out.println("heart");
case CLUB -> System.out.println("club");
case SPADE -> System.out.println("spade");
case DIAMOND -> System.out.println("diamond");
default -> System.out.println("unknown");
}

Select 1 option(s):

heart

unknown

It will not compile.

It will throw a NullPointerException at run time.

None

Q10. Consider the following classes...

class Point { int x, y; }
class ColoredPoint extends Point { int color; }
class Test
{
static void test(ColoredPoint p, Point q)
{
System.out.println("(ColoredPoint, Point)");
}
static void test(Point p, ColoredPoint q)
{
System.out.println("(Point, ColoredPoint)");
}
public static void main(String[] args)
{
ColoredPoint cp = new ColoredPoint();
test(cp, cp);
}
}

The above code will print (ColoredPoint, Point) when compiled and run.

Select 1 option(s):

True

False

None

Q11. Consider the following class...

class TestClass{
void probe(Object x) { System.out.println("In Object"); } //3

void probe(Number x) { System.out.println("In Number"); } //2

void probe(Integer x) { System.out.println("In Integer"); } //2

void probe(Long x) { System.out.println("In Long"); } //4

public static void main(String[] args){
double a = 10;
new TestClass().probe(a);
}
}

What will be printed?

Select 1 option(s):

In Number

In Object

In Long

In Integer

It will not compile.

None

Q12. Which of the following code fragments will successfully initialize a two-dimensional array of chars named cA with a size such that cA[2][3] refers to a valid element?

1.
char[][] cA = { { 'a', 'b', 'c' }, { 'a', 'b', 'c' } };
2.
char cA[][] = new char[3][];
for (int i=0; i<cA.length; i++) cA[i] = new char[4];
3.
char cA[][] = { new char[ ]{ 'a', 'b', 'c' } , new char[ ]{ 'a', 'b', 'c' } };
4
char cA[3][2] = new char[][] { { 'a', 'b', 'c' }, { 'a', 'b', 'c' } };
5.
char[][] cA = { "1234", "1234", "1234" };

6.
var cA[][] = new char[3][];
for (var i=0; i<cA.length; i++) cA[i] = new char[4];

Select 1 option(s):

1, 3

4, 5

2, 3

1, 2, 3

2, 6

1, 3, 6

2, 3, 6

None

Q13. Given:

class Base{
public List transform(Set list){
//valid code
};
}

class Derived extends Base{
*INSERT CODE HERE*
//valid code
}
}

What can be inserted in the above code?

Select 2 option(s):

public List< String > transform(Set< String > list){

public List< Object > transform(Set< CharSequence > list){

public ArrayList< CharSequence > transform(Set< CharSequence > list){

public List< StringBuilder > transform(Set< CharSequence > id){

public List< Integer > transform(TreeSet< CharSequence > id){

public ArrayList< String > transform(Set< String > id){

Q14. Assuming that the local time when the following code is executed is 9.30 AM, what will it print?

LocalTime now = LocalTime.now();
LocalTime gameStart = LocalTime.of(10, 15);
long timeConsumed = 0;
long timeToStart = 0;
if(now.isAfter(gameStart)){
timeConsumed = gameStart.until(now, ChronoUnit.HOURS);
}else{
timeToStart = now.until(gameStart, ChronoUnit.HOURS);
}
System.out.println(timeToStart + " " + timeConsumed);

Select 1 option(s):

0 45

0 0

45 0

None of the above

None

Q15. What will the following code print when compiled and run?

import java.io.Serializable;
class Booby{
int i; public Booby(){ i = 10; System.out.print("Booby"); }
}
class Dooby extends Booby implements Serializable {
int j; public Dooby(){ j = 20; System.out.print("Dooby"); }
}
class Tooby extends Dooby{
int k; public Tooby(){ k = 30; System.out.print("Tooby"); }
}
public class TestClass {
public static void main(String[] args) throws Exception{

var t = new Tooby();
t.i = 100;
var oos = new ObjectOutputStream(new FileOutputStream("c:\\temp\\test.ser"));
oos.writeObject(t); oos.close();

var ois = new ObjectInputStream(new FileInputStream("c:\\temp\\test.ser"));
t = (Tooby) ois.readObject();ois.close();

System.out.println(t.i+" "+t.j+" "+t.k);
}
}

Select 1 option(s):

Booby Dooby Tooby 100 20 30

Booby Dooby Tooby Booby Dooby Tooby 10 20 30

Booby Dooby Tooby Booby 10 20 30

Booby Dooby Tooby Booby 0 20 30

Booby Dooby Tooby Booby 100 20 30

Booby Dooby Tooby Booby Dooby Tooby 100 20 30

None

Q16. Consider the following code:

import java.util.*;
public class TestClass
{
static String[] sa = { "charlie", "bob", "andy", "dave" };
public static void main(String[] args)
{
// 1 insert code here.
}
}

Which of the given options (independent of each other or together) must be inserted at //1 so that it will print 2?

Select 2 option(s):

System.out.println(Arrays.search(sa, "andy"));

System.out.println(Arrays.linearSearch(sa, "andy"));

Arrays.sort(sa);

System.out.println(Arrays.binarySearch(sa, "charlie"));

Only option 2 is enough.

Q17. Given:

class Booby{
}
class Dooby extends Booby{
}
class Tooby extends Dooby{
}

and the following declarations:

var bL = new ArrayList();
var tL = new ArrayList();

List bV = //code for initialization
List dV = //code for initialization

Which of the following statements are valid?

Select 4 option(s):

dV.add(new Dooby(){ });

bV = bL;

dV = bL;

bV = tL;

dV = tL;

bV.add(new Dooby(){ });

Q18. What will the following code snippet print?

Object t = Integer.valueOf(107);
int k = (Integer) t.intValue()/9;
System.out.println(k);

Select 1 option(s):

It will not compile.

It will throw an exception at runtime.

None

Q19. In which sequence will the characters a, b, and, c be printed by the following program?

import java.util.* ;
public class ListTest{
public static void main(String args[]){
List s1 = new ArrayList( );
s1.add("a");
s1.add("b");
s1.add(1, "c");
List s2 = new ArrayList( s1.subList(1, 1) );
s1.addAll(s2);
System.out.println(s1);
}
}

Select 1 option(s):

The sequence a, b, c is printed.

The sequence a, b, c, b is printed.

The sequence a, c, b, c is printed.

The sequence a, c, b is printed.

None of the above.

None

Q20. Given:

1. Java source file location: src/moduleA/a/A.java
2. Expected class file location: out/moduleA/a/A.class

Which of the following commands will generate A.class in the expected directory?

(Assume that all directory paths are relative to the current directory.)

Select 1 option(s):

javac --module-path src --output-path out src/moduleA/a/A.java

javac --module-source-path src --output-path out src/moduleA/a/A.java

javac --module-source-path src -d out src/moduleA/a/A.java

javac --module-source-path src --module-path out src/moduleA/a/A.java

None

Q21. Consider the following interface definition:

interface Bozo{
int type = 0;
public void jump();
}

Now consider the following class:

public class Type1Bozo implements Bozo{
public Type1Bozo(){
type = 1;
}

public void jump(){
System.out.println("jumping..."+type);
}

public static void main(String[] args){
Bozo b = new Type1Bozo();
b.jump();
}
}

What will the program print when compiled and run?

Select 1 option(s):

jumping...0

jumping...1

This program will not compile.

It will throw an exception at runtime.

None

Q22. What will be the output of the following class:

public class TestClass{
public void testRefs(String str, StringBuilder sb){
str = str + sb.toString();
sb.append(str);
str = null;
sb = null;
}
public static void main(String[] args){
String s = "aaa";
StringBuilder sb = new StringBuilder("bbb");
new TestClass().testRefs(s, sb);
System.out.println("s="+s+" sb="+sb);
}
}

Select 1 option(s):

s=aaa sb=bbb

s=null sb=null

s=aaa sb=null

s=null sb=bbbaaa

s=aaa sb=bbbaaabbb

None

Q23. What will the code shown below print when run?

class Wrapper{
int w = 10;
}

public class TestClass{

static Wrapper changeWrapper(Wrapper w){
w = new Wrapper();
w.w += 9;
return w;
}

public static void main(String[] args){
var w = new Wrapper();
w.w = 20;
changeWrapper(w);
w.w += 30;
System.out.println(w.w);
w = changeWrapper(w);
System.out.println(w.w);
}
}

Select 2 option(s):

Q24. What will the following code snippet print:

Float f = null;
try{
f = Float.valueOf("12.3");
String s = f.toString();
int i = Integer.parseInt(s);
System.out.println(""+i);
}
catch(Exception e){
System.out.println("trouble : "+f);
}

Select 1 option(s):

trouble : null

trouble : 12.3

trouble : 0.0

None

Q25. Consider the following code:

class A{
A() { print(); }
void print() { System.out.print("A "); }
}
class B extends A{
int i = 4;
public static void main(String[] args){
A a = new B();
a.print();
}
void print() { System.out.print(i+" "); }
}

What will be the output when class B is run ?

Select 1 option(s):

It will print A 4

It will print A A

It will print 0 4

It will print 4 4

None of the above.

None

Q26. What will be the result of attempting to compile the following program?

public class TestClass{
long l1;
public void TestClass(long pLong) { l1 = pLong ; } //(1)
public static void main(String args[]){
TestClass a, b ;
a = new TestClass(); //(2)
b = new TestClass(5); //(3)
}
}

Select 1 option(s):

A compilation error will be encountered at (1), since constructors should not specify a return value.

A compilation error will be encountered at (2), since the class does not have a default constructor.

A compilation error will be encountered at (3).

The program will compile correctly.

It will not compile because the type of the parameter passed on line //3 does not match the parameter type on line //1.

None

Q27. Given:

class Person{
String name;
String dob;
public Person(String name, String dob){
this.name = name; this.dob = dob;
}
}
class MySorter {
public int compare(Person p1, Person p2){
return p1.dob.compareTo(p2.dob);
}
}
public class SortTest {
public static int diff(Person p1, Person p2){
return p1.dob.compareTo(p2.dob);
}

public static int diff(Date d1, Date d2){
return d1.compareTo(d2);
}
public static void main(String[] args) {
ArrayList al = new ArrayList();
al.add(new Person("Paul", "01012000"));
al.add(new Person("Peter", "01011990"));
al.add(new Person("Patrick", "01012002"));

INSERT CODE HERE
}
}

and the following lines of code:
I java.util.Collections.sort(al, (p1, p2)->p1.dob.compareTo(p2.dob));

II java.util.Collections.sort(al, SortTest::diff);

III java.util.Collections.sort(al, new MySorter()::compare);

IV java.util.Arrays.sort(al, SortTest::diff);

How many of the above lines can be inserted into the given code, independent of each other, to sort the list referred to by al?

Select 1 option(s):

None of these

None

Q28. Which of the given options if put at //1 will compile without any error?

public class TestClass
{
public class A
{
}
public static class B
{
}
public void useClasses()
{
//1
}
}

Select 1 option(s):

new TestClass().new A();

new TestClass.B();

new A();

new TestClass.A();

All of these are valid.

None

Q29. You are creating an enthu.questionbank module that depends on enthu.internal.db and enthu.external.feeds modules. Which of the following files correctly defines this module?

Select 1 option(s):

//In file module-info.java:
module enthu.questionbank{
requires enthu.internal.db, enthu.external.feeds;
}

//In file module-info.java:
module enthu.questionbank{
uses enthu.internal.db, enthu.external.feeds;
}

//In file module-info.java:
module enthu.questionbank{
import enthu.internal.db;
import enthu.external.feeds;
}

//In file module-info.java:
module enthu.questionbank{
require enthu.internal.db;
require enthu.external.feeds;
}

None of the above are valid.

None

Q30. Given a Course class with appropriate constructor and methods and the following code:

List s1 = //create a list with a few Course objects
String testCategory = "Java";
Integer comparisonCode = 0;
long l = s1.stream()
.peek(new Consumer(){
public void accept(Course c){
c.printPassPercent();
}})
.map(c -> testCategory.compareToIgnoreCase(c.getCategory()))
.filter(a->comparisonCode.equals(a))
.count();
System.out.println(l);

Which of the method arguments can be changed to use method references?

Select 2 option(s):

Course::printPassPercent

testCategory::compareToIgnoreCase

comparisonCode::equals

comparisonCode::equals(0)

Integer::equals(comparisonCode)

Course::getId == comparisonCode

Q31. Given:

var data = new ArrayList();
data.add("A");
data.add(100); //1
data.add("C");
data.set(0, 200); //2
data.remove(2); //3
data.set(2, 101L);//4
System.out.println(data);

What will be the output?

Select 1 option(s):

It will not compile.

Exception at run time on line marked //1.

Exception at run time on line marked //2.

Exception at run time on line marked //3.

Exception at run time on line marked //4.

[200, 100, 101]

None

Q32. Assuming that a file named "a.java" exists in c:\pathtest\ as well as in c:\pathtest\dir2, what will happen when the following code is compiled and run?

//imports not shown
public class MoveTest {

public static void main(String[] args) throws IOException {
Path p1 = Paths.get("c:\\pathtest\\a.java");
Path p2 = Paths.get("c:\\pathtest\\dir2\\a.java");
Files.move(p1, p2, StandardCopyOption.ATOMIC_MOVE);
Files.delete(p1);
System.out.println(p1.toFile().exists()+" "+
p2.toFile().exists());
}
}

Select 1 option(s):

It will not compile.

It will terminate cleanly after printing false true.

It will terminate cleanly after printing true true.

It will terminate cleanly after printing true false.

It will terminate cleanly after printing false false.

It will throw an exception at run time.

The outcome is JVM/platform dependent.

None

Q33. Given:

public class Device implements AutoCloseable{
boolean open = false;
public Device(){
open = true;
}

public String read() throws IOException{
throw new IOException("Can't read!");
}

public boolean isOpened(){
return open;
}

public void close(){
open = false;
System.out.println("Device closed");
}

public static void main(String[] args) {
Device d1 = new Device();
try(d1;
Device d2 = new Device();
Device d3 = new Device()){
d2.read();
}catch(Exception e){
System.out.println("Got Exception "+e.getMessage());
}
}
}

What is the status of Device objects at the end of the try/catch blocks?

Select 1 option(s):

All three will be closed.

d1 and d3 will be closed but d2 will remain open.

d1 and d2 will be closed but d3 will remain open.

d2 will be closed but d1 and d3 will remain open.

All three will remain opened.

Compilation failure.

None

Q34. What will be the output when the following program is run?

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

Select 1 option(s):

0 0 will be printed twice.

0 0 will be printed once.

It will keep on printing 0 0

It will not compile.

It will print 0 0 and then 0 1.

None

Q35. What can be inserted in the code below so that it will print 1 2 3?

class MyProcessor{
Integer value;
public MyProcessor(Integer value){
this.value = value;
}
public void process(){
System.out.println(value+" ");
}
}
public class TestClass {

public static void main(String[] args) {
List ls = Arrays.asList(1, 2, 3);

INSERT CODE HERE
}
}

Select 1 option(s):

ls.stream()
.map(x->MyProcessor::new(x))
.forEach(MyProcessor::process);

ls.stream()
.map(MyProcessor::new)
.forEach(MyProcessor::process);

ls.stream()
.forEach((x)->process( MyProcessor::new ));

ls.stream()
.forEach(x->MyProcessor::new);

None

Q36. Given:

public class Movie{
private String title;
private String genre;
public Movie(String title, String genre){
this.title = title;
this.genre = genre;
}
//accessors not shown
}

and

Stream sm = Stream.of( new Movie("a1", "a"),
new Movie("a2", "a"),
new Movie("b1", "b"), new Movie("c1", null));

Which of the following code fragments will get you the map of all the genres and the number of movies belonging to each genre?

Select 1 option(s):

Map< Optional< String >, Long > gcount = sm.collect(
Collectors.groupingBy(
movie -> Optional.ofNullable(movie.getGenre()), Collectors.counting()
)
);

Map< String, Long > gcount = sm.collect(
Collectors.groupingBy(
movie -> Optional.ofNullable(movie.getGenre()), Collectors.counting()
)
);

Map< Optional< String >, Integer > gcount = sm.collect(
Collectors.groupingBy(
movie -> Optional.ofNullable(movie.getGenre()), Collectors.counting()
)
);

Map< Optional< String >, Long > gcount = sm.collect(
Collectors.groupingBy(
movie -> Optional.of(movie.getGenre()), Collectors.counting()
)
);

None

Q37. Consider the following code:

import java.util.concurrent.*;

public class ThreadPoolTest {
public static void main(String[] args) {
Runnable r = ()-> System.out.println("In Runnable");
Callable c = ()-> { System.out.println("In Callable"); return 0; };
var es = Executors.newCachedThreadPool();

//INSERT CODE HERE

es.shutdown();

}

}

What can be inserted in the above code so that both - Runnable r and Callable c - will be executed?

Select 1 option(s):

es.submit(c);
es.submit(r);

es.execute(c);
es.execute(r);

es.add(c);
es.add(r);

Future< Integer > fi1 = es.submit(c);
Future< Integer > fi2 = es.submit(r);

Future< Integer > fi1 = es.submit(c);
Future< Object > fi2 = es.submit(r);

None

Q38. What will the following code print?

List ls = Arrays.asList(1, 2, 3);
Function func = a->a*a; //1
ls.stream().map(func).peek(System.out::print); //2

Select 1 option(s):

Compilation error at //1

Compilation error at //2

149

123

It will compile and run fine but will not print anything.

None

Q39. Consider the following class and interface definitions (in separate files):

public class Sample implements IInt{
public static void main(String[] args){
Sample s = new Sample(); //1
int j = s.thevalue; //2
int k = IInt.thevalue; //3
int l = thevalue; //4
}
}
public interface IInt{
int thevalue = 0;
}

What will happen when the above code is compiled and run?

Select 1 option(s):

It will give an error at compile time at line //1.

It will give an error at compile time at line //2.

It will give an error at compile time at line //3

It will give an error at compile time at line //4.

It will compile and run without any problem.

None

Q40. Which line(s) of code in the following program will cause compilation errors?

public class TestClass{
var value = 0; //1
int otherValue = 10; //1
public static void main(var args[]) //2
{
var secondArg = Integer.parseInt(args[2]); //3
if( true == 2 > 10 ) //4
{
value = -10;
}
else{
value = secondArg;
}
for( ; otherValue>0; otherValue--) System.out.println("A"); //5
}
}

Select 3 option(s):

Q41. What will the following code print when run?

import java.util.*;
import java.text.*;

public class TestClass
{
public static void main(String[] args)
{
double amount = 123456.789;
Locale fr = new Locale("fr", "FR");
NumberFormat formatter = NumberFormat.getInstance(fr);
String s = formatter.format(amount) ;
formatter = NumberFormat.getInstance();
Number amount2 = formatter.parse(s);
System.out.println( amount + " " + amount2 );
}
}

Select 1 option(s):

It will always print two equal numbers.

It will always print two unequal numbers.

It will not compile.

It will throw an exception at runtime.

None of these.

None

Q42. Assuming that getValue returns an int, which of the following options can be used in the code below:

int x = getValue();
String s = INSERT CODE HERE

Select 2 option(s):

switch(x){
case 0 -> "Zero";
case 1 -> "One";
default -> "Invalid";
};

switch(x){
case 0 -> return "Zero";
case 1 -> return "One";
default -> return "Invalid";
};

switch(x){
case 0 -> yield "Zero";
case 1 -> yield "One";
default -> yield "Invalid";
};

switch(x){
case 0 -> "Zero";
case 1 -> "One";
default -> {
yield "Invalid";
}
};

switch(x){
case 0 -> "Zero";
case 1 -> "One";
};

switch(x){
case 0 -> "Zero";
case 1 -> "One";
default -> {
return "Invalid";
}
};

Q43. What will the following code print ?

class Test{
public static void main(String[] args){
int k = 1;
int[] a = { 1 };
k += (k = 4) * (k + 2);
a[0] += (a[0] = 4) * (a[0] + 2);
System.out.println( k + " , " + a[0]);
}
}

Select 1 option(s):

It will not compile.

4 , 4

25 , 25

13 , 13

None of the above.

None

Q44. Identify correct statements about -classpath and --module-path options while executing a java program.

Select 3 option(s):

A modular jar placed on the classpath results in a named application module.

A non-modular jar placed on the classpath results in an automatic module.

A non-modular jar placed on the module-path results in an automatic module.

A modular jar placed on the module-path results in a named application module.

If a package is available in a jar on the classpath as well as in another jar on the module-path, the one on the classpath is ignored.

Classpath or module-path are mutually exclusive i.e. only one of them should be used.

Q45. Given:

enum Coffee
{
ESPRESSO("Very Strong"), MOCHA("Bold"), LATTE("Mild");
public String strength;
Coffee(String strength)
{
this.strength = strength;
}
}

and the statement
System.out.println(Coffee.ESPRESSO);

What can be done so that the above statement will print Very Strong?

Select 1 option(s):

Insert the following in Coffee:
public String toString(){ return Coffee.values()[0]; }

Insert the following in Coffee:
String toString(){ return "Very Strong"; }

Insert the following in Coffee:
public String toString(){ return String.valueOf(Coffee.ESPRESSO);}

Insert the following in Coffee:
public String toString(){ return String.valueOf(strength);}

None

Q46. Which of the statements regarding the following code are correct?

public class TestClass{
static int a;
int b;
public TestClass(){
int c;
c = a;
a++;
b += c;
}
public static void main(String args[]) { new TestClass(); }
}

Select 1 option(s):

The code will fail to compile because the constructor is trying to access static members.

The code will fail to compile because the constructor is trying to use static member variable a before it has been initialized.

The code will fail to compile because the constructor is trying to use member variable b before it has been initialized.

The code will fail to compile because the constructor is trying to use local variable c before it has been initialized.

The code will compile and run without any problem.

None

Q47. What will the following code print?

List ls = Arrays.asList("Tom Cruise", "Tom Hart",
"Tom Hanks", "Tom Brady");
Predicate p = str->{
System.out.println("Looking...");
return str.indexOf("Tom") > -1;
};
boolean flag = ls.stream().filter(str->str.length()>8).allMatch(p);

Select 1 option(s):

It will not print anything.

It will not print anything but will throw an exception at run time.

Looking...
Looking...
Looking...
< exception stack trace >

Looking...
Looking...
Looking...

Looking...
Looking...
Looking...
Looking...

Looking...

None

Q48. Given:

double daaa[][][] = new double[3][][];
var d = 100.0;
double[][] daa = new double[1][1];

Which of the following statements can be added to the above code, independent of each other, without causing compilation or runtime errors?

Select 3 option(s):

daaa[0] = d;

daaa[0] = daa;

daaa[0] = daa[0];

daa[1][1] = d;

daa = daaa[0];

double[] newd = daa[0].clone();

Q49. As a part of an application, you have serialized and stored some objects of a class in the database. At another place in the same application, you deserialize those objects.

After a few months you determine that you need to add one new String field in the class.

Which of the following statements are correct regarding the above described situation?

Select 1 option(s):

The objects serialized earlier cannot be deserialized to the updated class objects.

Objects serialized earlier can be deserialized to the updated class objects by adding a new serialVersionUID field with a value of 0 to the updated class.

No special change is necessary in the updated class. Objects serialized earlier will be deserialized to the updated class objects but the newly added field will be null.

Old serialized objects can be deserialized only if the original class had explicitly defined a serialVersionUID field and if the updated class maintains the same value for that field.

It is possible to deserialize the older objects into the update class objects even if the original class did not explicitly define the serialVersionUID field.

None

Q50. Given:

import java.util.*;
class Student{ }

public class TestClass {

var students = new ArrayList(); //1

public static void main(String[] args) {

var student = new Student(); //2

var allStudents = new ArrayList(); //3

allStudents.add(student); //4

for(var s : allStudents){ //5
System.out.println(s);
}
Student s2 = allStudents.get(0); //6

var var = "what?"; //7

var ch = '\\t'; //8
}

}

Which lines will cause compilation error?

Select 3 option(s):

//1

//2

//3

//4

//5

//6

//7

//8

Time's up

[/ppwp]