Course Content
Java Extended
Java Extended
Final Keyword
How to prevent changing the value of a variable
For this purpose, Java has a keyword called final
. Let's consider a code snippet where we use this keyword:
Main
package com.example; public class Main { public static void main(String[] args) { int number = 10; final int finalNumber = 5; number = 15; finalNumber = 20; System.out.println(number); System.out.println(finalNumber); } }
You can see that in the code above, we have created two variables of type int
, but one of them is marked with the final
keyword. When we try to change the value of this variable, the compiler tells us about an error. Specifically, it indicates that we cannot modify a value that is marked with the final
keyword.
What can we use final
keyword for:
- To create constants. A constant is a variable whose value cannot be changed after it has been initialized. In Java, constants are always declared using the
final
keyword; - To indicate that the value of a variable is final and should not be modified;
- To prevent accidental modification of a final variable's value in our code.
Task
Your task is to add the final
keyword before the variables that I do not modify in this code to prevent me from accidentally changing them later.
Once you've completed this task, click the button below the code to check your solution.
Thanks for your feedback!
Final Keyword
How to prevent changing the value of a variable
For this purpose, Java has a keyword called final
. Let's consider a code snippet where we use this keyword:
Main
package com.example; public class Main { public static void main(String[] args) { int number = 10; final int finalNumber = 5; number = 15; finalNumber = 20; System.out.println(number); System.out.println(finalNumber); } }
You can see that in the code above, we have created two variables of type int
, but one of them is marked with the final
keyword. When we try to change the value of this variable, the compiler tells us about an error. Specifically, it indicates that we cannot modify a value that is marked with the final
keyword.
What can we use final
keyword for:
- To create constants. A constant is a variable whose value cannot be changed after it has been initialized. In Java, constants are always declared using the
final
keyword; - To indicate that the value of a variable is final and should not be modified;
- To prevent accidental modification of a final variable's value in our code.
Task
Your task is to add the final
keyword before the variables that I do not modify in this code to prevent me from accidentally changing them later.
Once you've completed this task, click the button below the code to check your solution.
Thanks for your feedback!
Final Keyword
How to prevent changing the value of a variable
For this purpose, Java has a keyword called final
. Let's consider a code snippet where we use this keyword:
Main
package com.example; public class Main { public static void main(String[] args) { int number = 10; final int finalNumber = 5; number = 15; finalNumber = 20; System.out.println(number); System.out.println(finalNumber); } }
You can see that in the code above, we have created two variables of type int
, but one of them is marked with the final
keyword. When we try to change the value of this variable, the compiler tells us about an error. Specifically, it indicates that we cannot modify a value that is marked with the final
keyword.
What can we use final
keyword for:
- To create constants. A constant is a variable whose value cannot be changed after it has been initialized. In Java, constants are always declared using the
final
keyword; - To indicate that the value of a variable is final and should not be modified;
- To prevent accidental modification of a final variable's value in our code.
Task
Your task is to add the final
keyword before the variables that I do not modify in this code to prevent me from accidentally changing them later.
Once you've completed this task, click the button below the code to check your solution.
Thanks for your feedback!
How to prevent changing the value of a variable
For this purpose, Java has a keyword called final
. Let's consider a code snippet where we use this keyword:
Main
package com.example; public class Main { public static void main(String[] args) { int number = 10; final int finalNumber = 5; number = 15; finalNumber = 20; System.out.println(number); System.out.println(finalNumber); } }
You can see that in the code above, we have created two variables of type int
, but one of them is marked with the final
keyword. When we try to change the value of this variable, the compiler tells us about an error. Specifically, it indicates that we cannot modify a value that is marked with the final
keyword.
What can we use final
keyword for:
- To create constants. A constant is a variable whose value cannot be changed after it has been initialized. In Java, constants are always declared using the
final
keyword; - To indicate that the value of a variable is final and should not be modified;
- To prevent accidental modification of a final variable's value in our code.
Task
Your task is to add the final
keyword before the variables that I do not modify in this code to prevent me from accidentally changing them later.
Once you've completed this task, click the button below the code to check your solution.