java socket编程中服务器指的是什么？ 客户端指的又是什么？

/服务端/
import javaioBufferedReader;
import javaioBufferedWriter;
import javaioIOException;
import javaioInputStreamReader;
import javaioOutputStreamWriter;
import javaioPrintWriter;
import javanetServerSocket;
import javanetSocket;
第四步，编写服务器端的主体代码，如下所示。
public class ServerCode
{
// 设置端口号
public static int portNo = 3333;
public static void main(String[] args) throws IOException
{
ServerSocket s = new ServerSocket(portNo);
Systemoutprintln("The Server is start: " + s);
// 阻塞,直到有客户端连接
Socket socket = saccept();
try
{
Systemoutprintln("Accept the Client: " + socket);
//设置IO句柄
BufferedReader in = new BufferedReader(new InputStreamReader(socket
getInputStream()));
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(socketgetOutputStream())), true);
while (true)
{
String str = inreadLine();
if (strequals("byebye"))
{
break;
}
Systemoutprintln("In Server reveived the info: " + str);
outprintln(str);
}
}
finally
{
Systemoutprintln("close the Server socket and the io");
socketclose();
sclose();
}
}
}
/客户端/
import javaioBufferedReader;
import javaioBufferedWriter;
import javaioIOException;
import javaioInputStreamReader;
import javaioOutputStreamWriter;
import javaioPrintWriter;
import javanetInetAddress;
import javanetSocket;
第二，编写客户端的主体代码，如下所示：
public class ClientCode
{
static String clientName = "Mike";
//端口号
public static int portNo = 3333;
public static void main(String[] args) throws IOException
{
// 设置连接地址类,连接本地
InetAddress addr = InetAddressgetByName("localhost");
//要对应服务器端的3333端口号
Socket socket = new Socket(addr, portNo);
try
{
Systemoutprintln("socket = " + socket);
// 设置IO句柄
BufferedReader in = new BufferedReader(new InputStreamReader(socket
getInputStream()));
PrintWrite out = new PrintWriter(BufferedWriter(new OutputStreamWriter(socketgetOutputStream())), true);
outprintln("Hello Server,I am " + clientName);
String str = inreadLine();
Systemoutprintln(str);
outprintln("byebye");
}
finally
{
Systemoutprintln("close the Client socket and the io");
socketclose();
}
}
}

1不知道你是不是因为没有学过Spring框架的使用，你可以去学习了解下Spring和SpirngMVC框架的使用。

2第二个、第三个问题我暂时不知道怎么讲，抱歉哈，嘿嘿

PrintWriter out = new PrintWriter(sgetOutputStream());
outwrite("你好!");
替换成
PrintStream out = new PrintStream(sgetOutputStream());
outprint("你好!");

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