一、TCP：用字符流传输信息
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[用字符流的要点提示]
1:
将套接字关闭之后，字符流自然也就关闭了，所以只需要socket.shutdownOutput();/socket.shutdownInput();
应为套接字开启的字节流封装在字符流Buffered里面，若果先关闭字符流bw.close()，将会关闭套接字。 抛出java.net.SocketException: Socket is closed异常,说明已经将套接字关闭。
2:必须要写入换行符bw.newLine();（或者在内容末尾加\n），这样在用BufferedReader的readerLine() 接收数据包的时候才能读取到一个换行信息，否则会出现读取错误。
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public class Tcpc { // 客户端
public static void main(String[] args) throwsUnknownHostException, IOException {
//1.创建套接字指定主机和端口
Socket socket = new Socket(InetAddress.getLocalHost(),8808);
//2打开输入输出流
InputStream is = socket.getInputStream();
OutputStream os = socket.getOutputStream();
//准备要撒送的数据
String send = "我是客户端，请求登录！";
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(os));
bw.write(send);
bw.newLine();
bw.flush();
socket.shutdownOutput();
//4.准备接受返回的信息，并用行读取
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String lin =br.readLine();
System.out.println("客户端开始接受信息！");
while(lin!=null){
System.out.println(lin);
lin=br.readLine();
}
//5关闭资源
socket.shutdownInput();
}
}
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public class Tcps { // 服务端
public static void main(String[] args) throws IOException {
//1创建套接字，到指定的端口接受信息
ServerSocket serversocket = new ServerSocket(8808);
//2监听客户端的消息
Socket socket = serversocket.accept();
//3.打开输入输出的流
InputStream is = socket.getInputStream();
OutputStream os = socket.getOutputStream();
//4封装一个行读取的流
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String lin = br.readLine();
while(lin!=null){
System.out.println(lin);
lin = br.readLine();
}
socket.shutdownInput();
//5给客户端一反馈
String replay="我是服务端，允许登录！";
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(os));
bw.write(replay);
bw.newLine();
bw.flush();
//6关闭资源
socket.shutdownOutput();
}
}
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二、TCP字节流传输信息
TCP:字节流传输信息
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public class Tcpc { //客户端
public static void main(String[] args) throwsUnknownHostException, IOException {
//1.创建套接字指定主机和端口
Socket socket = new Socket(InetAddress.getLocalHost(),8808);
//2打开输入输出流
InputStream is = socket.getInputStream();
OutputStream os = socket.getOutputStream();
//准备要撒送的数据
String send = "我是客户端，请求登录！";
os.write(send.getBytes());
socket.shutdownOutput();
//4.准备接受返回的信息，并用行读取
System.out.println("客户端接受完毕！");
byte[] by = new byte[1024];
is.read(by);
System.out.println(new String(by,0,by.length));
//5关闭资源
socket.shutdownInput();
}
}
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public class Tcps { //服务端
public static void main(String[] args) throws IOException {
//1创建套接字，到指定的端口接受信息
ServerSocket serversocket = new ServerSocket(8808);
//2监听客户端的消息
Socket socket = serversocket.accept();
//3.打开输入输出的流
InputStream is = socket.getInputStream();
OutputStream os = socket.getOutputStream();
//4封装一个行读取的流
System.out.println("服务端接收完毕！");
byte[] by = new byte[1024];
is.read(by);
System.out.println(new String(by,0,by.length));
socket.shutdownInput();
//5给客户端一反馈
String replay="我是服务端，允许登录！";
System.out.println("服务端反馈完毕！");
os.write(replay.getBytes());
//6关闭资源
socket.shutdownOutput();
}
}