【发布时间】:2017-07-02 10:01:50
【问题描述】:
大家好,我在通过 java 中的套接字发送 2 个字符串时遇到问题。 我有从客户端获取用户名和密码并将其发送到服务器的 UI。我的问题是 2 部分:1-我无法在我的服务器中获取字符串用户名 2-当客户端发送用户名时,在发送密码之前套接字已关闭这是我的代码,请帮助我。 主要目的是从 UI(客户端)获取 2 个字符串用户名和密码,并通过套接字将它们发送到服务器。
服务器:
package finalproject;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class Server
{
ServerSocket listener;
Socket socket;
OutputStream out ;
InputStream in;;
InputStreamReader reader;
OutputStreamWriter writer;
String massage;
public void connectserver() throws IOException
{
listener = new ServerSocket(9097);
System.out.println("Server is running on port 9097 ...");
}
public void waitforclient() throws IOException
{
socket = listener.accept();
System.out.println("A new client connected to the server");
}
public void startstreamsserver() throws IOException
{
in = socket.getInputStream();
out = socket.getOutputStream();
writer = new OutputStreamWriter(out);
reader = new InputStreamReader(in);
System.out.println("Server streams are ready");
}
public void closestreamsserver() throws IOException
{
writer.close();
reader.close();
}
public void getinfoserver() throws IOException
{
try
{
reader.read();
System.out.println(reader);
System.out.println("input is : " + reader.toString());
}
catch(IOException IOE)
{
IOE.printStackTrace();//if there is an error, print it out
}
}
}
客户:
package finalproject;
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Client
{
Socket socket;
OutputStream out1;
InputStream in1;
OutputStreamWriter writer;
InputStreamReader reader;
String massage;
JFrame frame;
BorderLayout blayout;
JButton center;
JButton south;
FlowLayout fLoyout;
JLabel jb1;
JTextField name;
JLabel jb2;
JTextField pass;
JLabel jb7;
JPanel cpanel;
JPanel spanel;
public void connectclient() throws IOException
{
socket = new Socket("localhost", 9097);
System.out.println("connect to server on port 9097");
}
public void startstreamsclient() throws IOException
{
in1 = socket.getInputStream();
out1 = socket.getOutputStream();
writer = new OutputStreamWriter(out1);
reader = new InputStreamReader(in1);
System.out.println("Client streams are ready");
}
public void closestreamsclient() throws IOException
{
writer.close();
reader.close();
}
public void loginformclient()
{
frame = new JFrame();
frame.setVisible(true);
frame.setSize(500, 600);
blayout = new BorderLayout();
center = new JButton();
south = new JButton();
frame.setLayout(blayout);
fLoyout = new FlowLayout(FlowLayout.CENTER);
center.setLayout(fLoyout);
south.setLayout(fLoyout);
jb1 = new JLabel("Username :");
name = new JTextField(20);
center.add(jb1);
center.add(name);
jb2 = new JLabel("Password :");
pass = new JTextField(30);
center.add(jb2);
center.add(pass);
jb7 = new JLabel("Save");
south.add(jb7);
cpanel = new JPanel();
cpanel.add(center);
spanel = new JPanel();
south.addActionListener((ActionEvent ae) -> {
try
{
writer.write(name.getText());
writer.flush();
writer.write(pass.getText());
writer.flush();
writer.close();
}
catch (IOException ex)
{
Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
}
});
spanel.add(south);
cpanel.setLayout(new BoxLayout(cpanel, BoxLayout.Y_AXIS));
frame.add(cpanel, BorderLayout.CENTER);
frame.add(spanel, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
和我的主要课程:
package finalproject;
import java.io.IOException;
import javax.swing.JFrame;
public class Finalproject
{
public static void main(String[] args) throws IOException
{
//build Server & Client
Server server = new Server();
Client client = new Client();
//Start Server & Client
server.connectserver();
client.connectclient();
//Server wait for new connection
server.waitforclient();
//start the Streams
client.startstreamsclient();
server.startstreamsserver();
//Client send login information to Server
client.loginformclient();
//Server get information
server.getinfoserver();
}
}
但我在服务器中的输入是:
java.io.InputStreamReader@171fc7e
input is : java.io.InputStreamReader@171fc7e
【问题讨论】:
-
是什么让您认为 InputStreamReader.toString() 从阅读器读取并打印已读取的内容?阅读 javadoc。 Google for Java IO 教程。
-
我的方法是否正确。我通过套接字将我的字符串发送到我的服务器并通过 InputStreamReader 在服务器中读取它有什么问题你能解释一下吗?我不明白。
-
你永远不会在 Reader 上调用 read(),所以不,你永远不会在服务器上读取任何内容。再次阅读 InputStreamReader 的 javadoc 和 google for Java IO 教程,了解如何从 Reader 中读取数据。
-
再次阅读 javadoc。 StringReader 从字符串中读取。不是来自套接字 InputStream。那根本没有意义。 StringWriter 允许写入字符串,而不是套接字输出流。所以再一次,这没有任何意义。
-
你读过(),但你完全忽略了方法返回的内容。再次,谷歌搜索 Java IO 教程,并阅读您如何从阅读器中阅读。