What does final mean in java

The final keyword is used to mark constants and methods in Java as immutable and non-overridable. Constants are marked as unmodifiable using the final keyword to prevent accidental changes. Final methods cannot be overridden by subclasses. The final keyword provides immutability, safety, and code readability, but overuse may limit the flexibility of your code.

final in Java

In Java, the final keyword is used to mark constants and methods so that they Content is immutable and non-overridable.

Final of constants

When applied to a constant (variable), final means that the value of the variable cannot be modified. This essentially declares the variable as a constant and prevents accidental changes.

For example:

<code class="java">final int MY_CONSTANT = 42;</code>

final of a method

When applied to a method, final means that the method cannot be overridden. This means that subclasses cannot redefine this method.

For example:

<code class="java">final public void printMessage() {
    System.out.println("This message cannot be overridden.");
}</code>

Benefits of final

Using the final keyword has the following benefits:

• Enforce immutability: Ensure that constants and immutable methods remain unchanged, thereby improving the reliability of your code.
• Improve security: Prevent accidental or malicious modification of constants and methods.
• Enhance code readability: Indicates that a specific element is immutable or non-overridable, thereby improving code clarity.

Usage Precautions

When using the final keyword, you need to pay attention to the following matters:

• Once declared as final, Constants or methods cannot be changed.
• Final methods can be inherited, but cannot be overridden.
• An element should be marked final only if it needs to remain unchanged. Excessive use of final may limit the scalability and flexibility of your code.

The above is the detailed content of What does final mean in java. For more information, please follow other related articles on the PHP Chinese website!