How to Properly Exit a Java Application Programmatically

What is the most effective method to programmatically exit a Java application?

System.exit(0);

In Java, there are several approaches to terminate a program. The most common and reliable way to quit a Java application is by using the `System.exit(int status)` method, where the integer indicates the exit status. A status of 0 typically signifies a normal termination, while any non-zero value indicates an error or abnormal termination.

public class ExitExample {
    public static void main(String[] args) {
        System.out.println("Application is exiting...");
        System.exit(0);  // Normal termination
    }
}

Causes

• User request to close the application.
• Programmatic conditions that require quitting (e.g., errors).
• Completion of the application's main tasks.

Solutions

• Use `System.exit(0)` for normal termination.
• Handle exceptions properly and invoke `System.exit(1)` for abnormal exits.
• Ensure to close any resources like file handlers and database connections before exiting.

Mistake: Forgetting to close resources before exiting.

Solution: Always close any open resources, such as files and database connections, before calling System.exit.

Mistake: Using System.exit() inside GUI applications (e.g., Swing or JavaFX) without proper event handling.

Solution: In GUI applications, use window listeners to trigger exiting and ensure all windows are disposed of.