The role of final class in java

The role of final classes in Java: Class immutability: final classes cannot be extended or modified to ensure consistent behavior. Methods cannot be overridden: final methods cannot be overridden in subclasses to prevent accidental changes. Variable constants: final variables become constants once initialized and cannot be reassigned.

The role of final class in Java

The final keyword is used in Java to declare an immutable class. method or variable. It ensures that a class, method or variable cannot be modified or overwritten after creation.

Function

• Class immutability: final class cannot be extended or modified, ensuring that its behavior is always consistent.
• Methods cannot be overridden: final methods cannot be overridden in subclasses to prevent behavior from being accidentally changed.
• Variable constancy: final variables become constants once initialized and cannot be reassigned.

Classes

Declaring a class as final means that it cannot be extended. This is useful, for example, when the class represents an abstract concept or should not be extended. For example:

<code class="java">public final class String {
    // ...
}</code>

Method

Declaring a method as final means it cannot be overridden in a subclass. This is useful, for example, when a method performs critical operations and should not be changed. For example:

<code class="java">public class Person {
    public final String getName() {
        // ...
    }
}</code>

Variable

Declaring a variable as final means that it cannot be reassigned. This is useful, for example, when the variable stores important data and should not be accidentally changed. For example:

<code class="java">public class Configuration {
    private final String apiKey;

    public Configuration(String apiKey) {
        this.apiKey = apiKey;
    }
}</code>

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