• Placement Questions

Placement Papers with Solutions

(#M40167123) JAVA QUESTION StringBuilder vs StringBuffer Keep an EYE

class MyLogger
{
private StringBuilder logger = new StringBuilder();
public void log(String message, String user)
{
logger.append(message);
logger.append(user);
}
}

The programmer must guarantee that a single MyLogger object works properly for a multi threaded system. How must this code be changed to be thread-safe?

A. Replace StringBuilder with StringBuffer

B. Replace StringBuilder with just a String object and use the string concatenation (+=) within the log method.

C. No change is necessary, the current MyLogger code is already thread-safe.

D. Synchronize the log method

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (0) Submit Your Solution

(#M40167122) JAVA QUESTION Output Keep an EYE

What is the output of the following program?

import java.util.regex.*;

class Test
{
public static void main(String args[])
{
Pattern p = Pattern.compile(".ech");
Matcher m = p.matcher("tech");
boolean b = m.matches();
System.out.println(b);
}
}

A. true
B. false
C. Compilation Error
D. Runtime Error

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (1) Submit Your Solution

(#M40167121) JAVA QUESTION StringBuilder vs StringBuffer Keep an EYE

StringBuilder is less efficient and slower than StringBuffer. State true or false.

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (1) Submit Your Solution

(#M40167120) JAVA QUESTION Matcher class Keep an EYE

Consider the below statements.

Statement 1 : Matcher class interprets the pattern in a String

Statement 2 : Matcher class matches the regular expression against the text provided

Which of the following is true?

A. Statement 2 alone is correct.
B. Both Statement 1 and 2 are incorrect.
C. Statement 1 alone is correct.
D. Both Statement 1 and 2 are correct

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (1)   (1) Submit Your Solution

(#M40167119) JAVA QUESTION equals() vs == based question Keep an EYE

What is the output of the following program?

import java.util.Arrays;

class Test
{
public static void main(String args[])
{
String[] cities = new String[]{"London", "Paris", "NewYork", "HongKong", "Tokyo"};
String[] metros = new String[]{"London", "Paris", "NewYork", "HongKong", "Tokyo"};
String[] capitals = cities;
System.out.println("cities == metros : " + (cities == metros));
System.out.println("cities == capitals : " + (cities == capitals));
System.out.println("cities.equals(metros) : " + cities.equals(metros));
System.out.println("cities.equals(capitals) : " + cities.equals(capitals));
System.out.println("Arrays.equals(cities, metros) : " + Arrays.equals(cities, metros));
System.out.println("Arrays.equals(cities, capitals) : " + Arrays.equals(cities, capitals));
}
}


A. cities == metros : false
cities == capitals : true
cities.equals(metros) : true
cities.equals(capitals) : true
Arrays.equals(cities, metros) : false
Arrays.equals(cities, capitals) : true

B. cities == metros : false
cities == capitals : true
cities.equals(metros) : true
cities.equals(capitals) : true
Arrays.equals(cities, metros) : true
Arrays.equals(cities, capitals) : true

C. cities == metros : false
cities == capitals : true
cities.equals(metros) : false
cities.equals(capitals) : true
Arrays.equals(cities, metros) : true
Arrays.equals(cities, capitals) : true

D. cities == metros : false
cities == capitals : true
cities.equals(metros) : false
cities.equals(capitals) : true
Arrays.equals(cities, metros) : true
Arrays.equals(cities, capitals) : false

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (0) Submit Your Solution

(#M40167118) JAVA QUESTION Number of string objects Keep an EYE

public String makingStrings()
{
String str = "Welcome";

str = str.substring(1, 5);

str = str.toUpperCase();

return str;
}

How many String objects are created in the heap when this method is invoked?

A. 4
B. 2
C. 3
D. 1

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (2)   (1) Submit Your Solution

(#M40167117) JAVA QUESTION Access Modifiers Keep an EYE

Given a method in a public class, ________ access modifier must be used to restrict access to that method to only the other members of the same class.

A. final
B. private
C. protected
D. default

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (0) Submit Your Solution

(#M40167116) JAVA QUESTION Java Polymorphism question Keep an EYE

What is the output of the following program?

class Icecream
{
public void displayName(String s)
{
System.out.println(s+" "+"Icecream");
}
public void describe(String s)
{
System.out.println(s+" "+"Icecream: Ice cream is a sweetened frozen food typically eaten as a snack or dessert. ");
}
}

class Faloodeh extends Icecream
{
public void displayName(String s)
{
System.out.println(s+" "+"Faloodeh ");
}

public void describe(String s)
{
System.out.println(s+" "+"Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream ");
}
}

public class Test
{
public static void main(String arg[])
{
Icecream a = new Faloodeh();
Faloodeh b = (Faloodeh)a;
a.displayName("test");
b.displayName("test");
a.describe("test");
b.describe("test");
}
}

A. test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh
test Faloodeh

B. test Faloodeh
test Faloodeh
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream

C. test Faloodeh
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh

D. test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream
test Faloodeh
test Faloodeh
test Faloodeh: Faloodeh is often served alongside Persian-style dairy-based ice cream

Asked In Java Jax (1 year ago)

Unsolved Read Solution (1)

Is this Puzzle helpful?   (4)   (3) Submit Your Solution Output

(#M40167115) JAVA QUESTION Inheritance relationship in Java Keep an EYE

Which of the following statements are correct with respect to inheritance relationship in java?

A. object of subclass referenced by super class type can invoke super class methods
B. object of subclass referenced by super class type can access newly defined sub class variables
C. object of subclass referenced by super class type can access super class variables
D. object of subclass referenced by super class type can invoke overridden sub class methods
E. object of subclass referenced by super class type can invoke newly defined sub class methods

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (1) Submit Your Solution Technical

(#M40167114) JAVA QUESTION Java question Keep an EYE

What will be the output of the following program?

class A
{
public void test()
{
System.out.println("Class A");
}
}
class Trial extends A
{
public void test()
{
System.out.println("Class Trial");
}
public static void main(String args[])
{
Trial object = (Trial)new A();
object.test();
}
}

A. Runtime Error
B. Compile Time Error
C. Class A
D. Class Trial

Asked In Java Jax (1 year ago)

Unsolved

Is this Puzzle helpful?   (0)   (0) Submit Your Solution Output