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web technology Online Quiz - 115

Description: web technology Online Quiz - 115
Number of Questions: 20
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Tags: web technology
Attempted 0/20 Correct 0 Score 0

Which of the following are primitive types?

  1. byte

  2. String

  3. integer

  4. Float


Correct Option: A

Choose the technologies used in view part of MVC architecture

  1. HTML

  2. CSS

  3. EJB

  4. Servlets


Correct Option: A,B

Controller in PS Framework is

  1. ps.xml

  2. Action controller

  3. JSP file

  4. Servlet


Correct Option: A,B

Which one does not extend java.lang.Number

  1. Integer

  2. Boolean

  3. Character

  4. Long


Correct Option: A,B
Explanation:

To solve this question, the user needs to know the concepts of inheritance and the java.lang.Number class. The java.lang.Number class is the superclass of all classes that encapsulate numbers in Java. These classes include Integer, Double, Long, Byte, Float, and Short.

Now, let's go through each option and explain why it extends or does not extend java.lang.Number:

A. Integer: This option extends java.lang.Number. Integer is a class that represents a 32-bit signed integer. It is a subclass of java.lang.Number and inherits its methods.

B. Boolean: This option does not extend java.lang.Number. Boolean is a class that represents a boolean value, which is either true or false. It does not inherit from java.lang.Number.

C. Character: This option does not extend java.lang.Number. Character is a class that represents a single character. It does not inherit from java.lang.Number.

D. Long: This option extends java.lang.Number. Long is a class that represents a 64-bit signed integer. It is a subclass of java.lang.Number and inherits its methods.

Therefore, the answer is:

The Answer is: B

Which statement(s) are true? (Choose all that apply.)

  1. Cohesion is the OO principle most closely associated with hiding implementation details

  2. Cohesion is the OO principle most closely associated with making sure that classes know about other classes only through their APIs

  3. Cohesion is the OO principle most closely associated with making sure that a class is designed with a single, well-focused purpose

  4. Cohesion is the OO principle most closely associated with allowing a single object to be seen as having many types


Correct Option: C

AI Explanation

To answer this question, we need to understand the concept of cohesion in object-oriented programming (OOP).

Cohesion is the measure of how closely the responsibilities and functionality of a class or module are related. It is an important principle in OOP design, as it promotes modularity, maintainability, and reusability.

Let's go through each statement to determine which one(s) are true:

A. Cohesion is the OO principle most closely associated with hiding implementation details. This statement is incorrect. Hiding implementation details is more closely associated with the principle of encapsulation, not cohesion.

B. Cohesion is the OO principle most closely associated with making sure that classes know about other classes only through their APIs. This statement is incorrect. Making sure that classes know about other classes only through their APIs is more closely associated with the principle of information hiding, not cohesion.

C. Cohesion is the OO principle most closely associated with making sure that a class is designed with a single, well-focused purpose. This statement is true. Cohesion is all about ensuring that a class has a single, well-focused purpose. It means that the responsibilities and functionality of a class should be closely related and focused on achieving a specific goal.

D. Cohesion is the OO principle most closely associated with allowing a single object to be seen as having many types. This statement is incorrect. Allowing a single object to be seen as having many types is more closely associated with the principle of polymorphism, not cohesion.

Based on the explanations above, the correct statement is:

C. Cohesion is the OO principle most closely associated with making sure that a class is designed with a single, well-focused purpose.

Therefore, the correct answer is C.

Given: ClassA has a ClassD Methods in ClassA use public methods in ClassB Methods in ClassC use public methods in ClassA Methods in ClassA use public variables in ClassB Which is most likely true? (Choose the most likely.)

  1. ClassD has low cohesion

  2. ClassA has weak encapsulation

  3. ClassB has weak encapsulation

  4. ClassB has strong encapsulation

  5. ClassC is tightly coupled to ClassA


Correct Option: C

Which is true? (Choose all that apply.)

  1. "X extends Y" is correct if and only if X is a class and Y is an interface

  2. "X extends Y" is correct if and only if X is an interface and Y is a class

  3. "X extends Y" is correct if X and Y are either both classes or both interfaces

  4. "X extends Y" is correct for all combinations of X and Y being classes and/or interfaces


Correct Option: C

Given: 3. public class Wind { 4. public static void main(String[] args) { 5. foreach: 6. for(int j=0; j<5; j++) { 7. for(int k=0; k< 3; k++) { 8. System.out.print(" " + j); 9. if(j==3 && k==1) break foreach; 10. if(j==0 || j==2) break; 11. } 12. } 13. } 14. } What is the result?

  1. 0 1 2 3

  2. 1 1 1 3 3

  3. 0 1 1 1 2 3 3

  4. 1 1 1 3 3 4 4 4

  5. 0 1 1 1 2 3 3 4 4 4

  6. Compilation fails


Correct Option: C
Explanation:

To solve this question, the user needs to understand how the nested for loops work and the use of break statements inside loops.

The code starts with a nested for loop. The outer loop iterates over values of j from 0 to 4, while the inner loop iterates over values of k from 0 to 2. Inside the inner loop, the code prints the value of j and checks two conditions using if statements:

  • If j is equal to 3 and k is equal to 1, the code executes a break statement with the label "foreach", which causes the program to exit both loops and continue executing after line 13.
  • If j is equal to 0 or 2, the code executes a break statement, which only exits the inner loop and continues executing from line 12.

Now, let's go through each option and find the correct answer:

A. 0 1 2 3:

This option is incorrect. The inner loop will only execute when j is equal to 1 or 3, and k is less than 3. When j is equal to 3 and k is equal to 1, the program exits both loops and does not print any more values. Thus, the correct output should not include 4.

B. 1 1 1 3 3:

This option is incorrect. The inner loop will only execute when j is equal to 1 or 3, and k is less than 3. When j is equal to 3 and k is equal to 1, the program exits both loops and does not print any more values. Thus, the correct output should not include 1 or 2.

C. 0 1 1 1 2 3 3:

This option is correct. The inner loop will only execute when j is equal to 1 or 3, and k is less than 3. When j is equal to 3 and k is equal to 1, the program exits both loops and does not print any more values. Thus, the correct output is 0 1 1 1 2 3 3.

D. 1 1 1 3 3 4 4 4:

This option is incorrect. The program never prints the value 4, since the outer loop only iterates from 0 to 4. When j is equal to 3 and k is equal to 1, the program exits both loops and does not print any more values. Thus, the correct output should not include 1 or 2.

E. 0 1 1 1 2 3 3 4 4 4:

This option is incorrect. The program never prints the value 4, since the outer loop only iterates from 0 to 4. When j is equal to 3 and k is equal to 1, the program exits both loops and does not print any more values. Thus, the correct output should not include 1, 2, or 4.

F. Compilation fails:

This option is incorrect. The code compiles without errors.

Therefore, the correct answer is:

The answer is: C. 0 1 1 1 2 3 3.

Given: 3. public class TestDays { 4. public enum Days { MON, TUE, WED }; 5. public static void main(String[] args) { 6. for(Days d : Days.values() ) 7. ; 8. Days [] d2 = Days.values(); 9. System.out.println(d2[2]); 10. } 11. } What is the result? (Choose all that apply.)

  1. TUE

  2. Wed

  3. The output is unpredictable

  4. Compilation fails due to an error on line 4

  5. Compilation fails due to an error on line 6

  6. Compilation fails due to an error on line 8


Correct Option: B

AI Explanation

To answer this question, let's go through each option to understand why it is correct or incorrect:

Option A) TUE - This option is incorrect. The output of the program is not TUE.

Option B) Wed - This option is correct. The output of the program is indeed "Wed" because the array d2 is assigned the values of the Days enum using the values() method. The values() method returns an array containing the enum constants in the order they were declared. In this case, the constants are declared as MON, TUE, WED, so d2[2] corresponds to WED.

Option C) The output is unpredictable - This option is incorrect. The output of the program is predictable and will always be "Wed".

Option D) Compilation fails due to an error on line 4 - This option is incorrect. There is no error on line 4. The enum Days is correctly declared and used.

Option E) Compilation fails due to an error on line 6 - This option is incorrect. There is no error on line 6. The for-each loop iterates over the enum constants correctly.

Option F) Compilation fails due to an error on line 8 - This option is incorrect. There is no error on line 8. The Days enum values are correctly assigned to the d2 array.

The correct answer is B) Wed. This option is correct because the program outputs "Wed" due to the assignment of Days enum values to the d2 array.

Which of the following are primitive types?

  1. byte

  2. String

  3. integer

  4. Float


Correct Option: A

Which one does not extend java.lang.Number

  1. Integer

  2. Boolean

  3. Character

  4. Long


Correct Option: B,C

If the method to be overridden has access type protected, choose access types among the following that a subclass can have,

  1. Protected

  2. Private

  3. Public

  4. Public & private

  5. Protected & Public


Correct Option: E
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