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programming languages Online Quiz - 53

Description: programming languages Online Quiz - 53
Number of Questions: 20
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Tags: programming languages
Attempted 0/20 Correct 0 Score 0

How can we give an pass phrase (like password) to a file ,to restrict its access ?

  1. vim +X file

  2. vim -X file

  3. vim -p file

  4. vim +p file


Correct Option: A

Linux aliases are recursive!!

  1. True

  2. False


Correct Option: A

What are the extended regular expression operators?

  1. +

  2. ?

  3. ^

  4. !

  5. *


Correct Option: A,B

Usually , system information present in this folder (in a unix system)?

  1. /sys

  2. /proc

  3. both

  4. none


Correct Option: C

In which scenario ,tail is being used for real time log file monitoring?

  1. tail -r logfile

  2. tail -n 5 logfile

  3. tail -f logfile

  4. tail -x logfile


Correct Option: C

What must be implemented by all Servlets?

  1. Servlet Interface

  2. servlet mapping

  3. Servlet Container

  4. None of the Above


Correct Option: A

Which of the following denote the type of protocol supported by HttpServlet?

  1. HTTP

  2. HTTPS

  3. Both (A) and (B)

  4. None of the Above


Correct Option: C

AI Explanation

To answer this question, we need to understand the purpose and functionality of the HttpServlet class in Java.

The HttpServlet class is a base class for creating web-based applications in Java. It is specifically designed to handle HTTP requests and responses. Therefore, the HttpServlet class supports the HTTP protocol.

Let's go through each option to understand why it is correct or incorrect:

Option A) HTTP - This option is correct because the HttpServlet class supports the HTTP protocol.

Option B) HTTPS - This option is correct because the HttpServlet class also supports the HTTPS protocol, which is a secure version of the HTTP protocol.

Option C) Both (A) and (B) - This option is correct because the HttpServlet class supports both the HTTP and HTTPS protocols.

Option D) None of the Above - This option is incorrect because the HttpServlet class does support one or both of the mentioned protocols.

Therefore, the correct answer is option C. This option is correct because the HttpServlet class supports both the HTTP and HTTPS protocols.

What is the number of bytes used by Java primitive long?

  1. The number of bytes is compiler dependent

  2. 2

  3. 4

  4. 8


Correct Option: D

Choose the false statement among these?

  1. Servlets are server side components

  2. Applets have GUI interface

  3. Servlets have GUI interface

  4. Applets are client side components


Correct Option: C

Implementations of servlets includes what?

  1. Apache web server

  2. java.net.HttpURLConnection class

  3. Java web server Tomcat

  4. None of the Above


Correct Option: C

Which of the following helps in garbage collection?

  1. final

  2. finaly

  3. finalize

  4. finalizer


Correct Option: C

AI Explanation

To answer this question, you need to understand the concept of garbage collection and the role of the finalize method in Java.

Option A) final - This option is incorrect because the final keyword is used to declare a constant or to make a variable, method, or class unchangeable.

Option B) finaly - This option is incorrect because there is no such keyword or method named finaly in Java.

Option C) finalize - This option is correct because the finalize method is a special method in Java that is called by the garbage collector before an object is garbage collected. It allows the object to perform any necessary cleanup operations before it is destroyed.

Option D) finalizer - This option is incorrect because there is no such keyword or method named finalizer in Java.

The correct answer is option C) finalize. This option is correct because the finalize method helps in garbage collection by allowing objects to perform cleanup operations before they are destroyed.

Consider the following piece of code byte x = 0; x += 1;

  1. Results in x having the value 1.

  2. Causes a compiler error.

  3. Will require a cast (byte) before 1.

  4. Will give syntax error.


Correct Option: A

What will be the result of compiling following code public class SampleClass { final int j ; public static void main(String[] arguments) { System.out.println(new SampleClass().j); } }

  1. The output is 0

  2. Will give compile error

  3. Will give runtime error

  4. The output is 1


Correct Option: B

All the wrapper classes (Integer, Boolean, Float, Short, Long, Double and Character)

  1. Are public

  2. Are final

  3. Are Serializable

  4. All the above


Correct Option: D

Which of the following statement is False?

  1. The throw keyword denotes a statement that causes an exception to be initiated

  2. A class that is declared without any access modifiers is said to have package or friendly access

  3. A class inherit the constructors of its superclass

  4. The primitive types are byte, char, short, int, long, float, double, and boolean


Correct Option: C

Which of the following is used to check in particular page the session will be alive or not?

  1. ifAlive()

  2. checkAlive()

  3. isAlive()

  4. None of the above


Correct Option: C

Choose the correct statement from the given choice?

  1. Arrays in Java are essentially objects

  2. It is not possible to assign one array to another. Individual elements of array can however be assigned.

  3. Array elements are indexed from 1 to size of array

  4. If a method tries to access an array element beyond its range, a compile warning is generated.


Correct Option: A

A constructor is used to

  1. Free memory

  2. Initialize a newly created object

  3. Import packages

  4. Create a JVM for applets


Correct Option: B

What does the following expression return? Math.max(Float.POSITIVE_INFINITY,Double.POSITIVE_INFINITY);

  1. Float.POSITIVE_INFINITY

  2. Double.POSITIVE_INFINITY

  3. runtime Exception

  4. None of the Above


Correct Option: B
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