一篇文章告诉你真实场景下服务端接口性能问题是如何解决的

public class RealData implements Callable<String> {
    protected String data;

    public RealData(String data) {
        this.data = data;
    }

    @Override
    public String call() throws Exception {
        // 通过sleep方法演示业务是缓慢的
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return data;
    }
}

public class Application {
    public static void main(String[] args) throws Exception {
        FutureTask<String> futureTask =
                new FutureTask<>(new RealData("name"));
        ExecutorService executor =
                Executors.newFixedThreadPool(1); // 使用线程池
        // 执行FutureTask，相当于上例中的client.request("name")发送请求
        executor.submit(futureTask);
        // 这里可以用一个sleep代替对其他业务逻辑的处理
        // 在处理这些业务逻辑的同时，RealData也在创建，充分利用等待时间
        Thread.sleep(2000);
        // 使用真实数据
        // 如果call()没有执行完成，仍会等待
        System.out.println("数据=" + futureTask.get());
    }
}

public class MultiThreadTest {
    public static void main(String[] args) {
        ThreadFactory threadFactory = new ThreadFactoryBuilder().setNameFormat("thread-%d").build();
        ExecutorService executor = new ThreadPoolExecutor(2, 5, 60L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(), threadFactory);
        executor.execute(new Runnable() {
            @Override
            public void run() {
               System.out.println("Hello, world!");
            }
        });
        System.out.println(" ===> Main Thread! ");
    }
}

public class NioTest {  
    static public void main( String args[] ) throws Exception {  
        FileInputStream fin = new FileInputStream("D:\\test.txt");  
        // 获取通道  
        FileChannel fc = fin.getChannel();  
        // 创建缓冲区  
        ByteBuffer buffer = ByteBuffer.allocate(1024);  
        // 读取数据到缓冲区  
        fc.read(buffer);  
        buffer.flip();  
        while (buffer.remaining()>0) {  
            byte b = buffer.get();  
            System.out.print(((char)b));  
        }  
        fin.close();  
    }  
}