简单的客户端给服务端发送数据:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;
/**
* Created by Administrator on 2017/7/12.
*/
public class BIOTest {
public static void main(String[] args) {
Thread server = new Thread(new Server());
server.start();
Thread client = new Thread(new Client());
client.start();
}
static class Server implements Runnable {
@Override
public void run() {
ServerSocket serverSocket = null;
SocketAddress socketAddress = new InetSocketAddress("127.0.0.1", 9999);
try {
serverSocket = new ServerSocket();
serverSocket.bind(socketAddress);
System.out.println("Server:accept");
Socket socket = serverSocket.accept();
try {
BufferedReader buf = new BufferedReader(new InputStreamReader(socket.getInputStream()));
System.out.println("Server:while");
while (true) {
System.out.println("Server:readLine");
String str = buf.readLine();
System.out.println("Server:====" + str);
}
} catch (Exception e) {
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
static class Client implements Runnable {
@Override
public void run() {
try {
Socket client = new Socket("127.0.0.1", 9999);
BufferedReader input = new BufferedReader(new InputStreamReader(System.in));
PrintStream out = new PrintStream(client.getOutputStream());
while (true) {
System.out.println("Client:readLine");
String str = input.readLine();
if (str.equals("Q"))
break;
//发送数据到服务端
out.println(str);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
accept、readLine都是阻塞的:
1、Socket socket = serverSocket.accept();
这里服务端等待客户端连接,一直没有客户端连接是不会往下走的。
2、String str = buf.readLine();
客户端连上之后,服务端不停的从流里面读数据,但是这里也是阻塞的,如果客户端一直不发数据也不会进入下一次循环。
3、String str = input.readLine();
客户端读取控制台输入也是阻塞的。
这里就能看到相比于NIO,等待消息时间+处理消息时间 等待消息时间什么事情都没有做,CPU空闲,但是当前线程是什么都干不了的。只能用多线程来充分利用CPU。