Bio和Nio 1.Bio是什么，bio有什么缺点
看下api 基于net 和io包 客户端: 1.1 public class BIOClient {
private static Charset charset = Charset.forName("UTF-8");
public static void main(String[] args) throws Exception {
Socket s = new Socket("127.0.0.1", 8080);
OutputStream out = s.getOutputStream();
Scanner scanner = new Scanner(System.in);
System.out.println("请输入：");
String msg = scanner.nextLine();
out.write(msg.getBytes(charset)); // 阻塞，写完成
scanner.close();
s.close();
}
}
server端: 1.2
public class BIOServer1 {
private static ExecutorService threadPool = Executors.newCachedThreadPool();
public static void main(String[] args) throws Exception {
ServerSocket serverSocket = new ServerSocket(8080);
System.out.println("tomcat 服务器启动成功");
while (!serverSocket.isClosed()) {
Socket request = serverSocket.accept();
System.out.println("收到新连接 : " + request.toString());
threadPool.execute(() -> {
try {
// 接收数据、打印
InputStream inputStream = request.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "utf-8"));
String msg;
while ((msg = reader.readLine()) != null) { // 阻塞
if (msg.length() == 0) {
break;
}
System.out.println(msg);
}
System.out.println("收到数据,来自："+ request.toString());
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
request.close();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
serverSocket.close();
}
}
可以看到 inputStream基本上都是基于阻塞api的； 1.2 什么是Nio 基于BIO的缺点加以改进，所涉及的api都是非阻塞的；当大量请求处理时也不会阻塞io线程；
看下api Java文件流抽象api的传统io操作基本都是阻塞的，他的磁盘的读写还是很慢的。 java1.4 Nio 基于通道和缓冲区 彻底颠覆传统IO的阻塞情况；
Nio Buffer
