How can we call a method asynchronously in Java?

In Java, one can use either multi-threading or callback functions to achieve asynchronous method invocation.

1. Using multithreading:
   You can create a new thread to execute a method and continue with other tasks. In Java, you can use the Thread class or the Runnable interface to create threads. For example:

public class AsyncExample {
    public static void main(String[] args) {
        Thread thread = new Thread(() -> {
            // 异步执行的方法
            asyncMethod();
        });
        thread.start();

        // 继续执行其他任务
        // ...
    }

    public static void asyncMethod() {
        // 异步方法的具体实现
        // ...
    }
}

1. Using callback functions:
   You can define a callback interface and pass the method that needs to be executed asynchronously as a parameter to another method, and then call the callback function after the method has been executed. For example:

public class AsyncExample {
    public static void main(String[] args) {
        asyncMethod(() -> {
            // 异步方法执行完成后的回调函数
            // ...
        });

        // 继续执行其他任务
        // ...
    }

    public static void asyncMethod(Callback callback) {
        // 异步方法的具体实现
        // ...

        // 执行完成后调用回调函数
        callback.onComplete();
    }

    interface Callback {
        void onComplete();
    }
}

Both methods can achieve asynchronous calling of a method, the choice between them depends on the specific needs and scenarios.