socket实现邮件发送

通过java的网络编程特性，完成邮件发送的功能，效果图如下：



首先新建一个maiTest的java项目，

然后新建GBC.java和MailTest.java文件

GBC.java代码如下：

package ch02;

import java.awt.*;

public class GBC extends GridBagConstraints
{

public GBC(int gridx, int gridy)
{
this.gridx = gridx;
this.gridy = gridy;
}

public GBC(int gridx, int gridy, int gridwidth, int gridheight)
{
this.gridx = gridx;
this.gridy = gridy;
this.gridwidth = gridwidth;
this.gridheight = gridheight;
}

public GBC setAnchor(int anchor)
{
this.anchor = anchor;
return this;
}

public GBC setFill(int fill)
{
this.fill = fill;
return this;
}

public GBC setWeight(double weightx, double weighty)
{
this.weightx = weightx;
this.weighty = weighty;
return this;
}

public GBC setInsets(int distance)
{
this.insets = new Insets(distance, distance, distance, distance);
return this;
}

public GBC setInsets(int top, int left, int bottom, int right)
{
this.insets = new Insets(top, left, bottom, right);
return this;
}

public GBC setIpad(int ipadx, int ipady)
{
this.ipadx = ipadx;
this.ipady = ipady;
return this;
}
}


MailTest.java的代码如下：
package ch02;

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.*;

public class MailTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
JFrame frame = new MailTestFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}

class MailTestFrame extends JFrame
{
public MailTestFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
setTitle("MailTest");

setLayout(new GridBagLayout());

add(new JLabel("From:"), new GBC(0, 0).setFill(GBC.HORIZONTAL));

from = new JTextField(20);
add(from, new GBC(1, 0).setFill(GBC.HORIZONTAL).setWeight(100, 0));

add(new JLabel("To:"), new GBC(0, 1).setFill(GBC.HORIZONTAL));

to = new JTextField(20);
add(to, new GBC(1, 1).setFill(GBC.HORIZONTAL).setWeight(100, 0));

add(new JLabel("SMTP server:"), new GBC(0, 2).setFill(GBC.HORIZONTAL));

smtpServer = new JTextField(20);
add(smtpServer, new GBC(1, 2).setFill(GBC.HORIZONTAL).setWeight(100, 0));

message = new JTextArea();
add(new JScrollPane(message), new GBC(0, 3, 2, 1).setFill(GBC.BOTH).setWeight(100, 100));

comm = new JTextArea();
add(new JScrollPane(comm), new GBC(0, 4, 2, 1).setFill(GBC.BOTH).setWeight(100, 100));

JPanel buttonPanel = new JPanel();
add(buttonPanel, new GBC(0, 5, 2, 1));

JButton sendButton = new JButton("Send");
buttonPanel.add(sendButton);
sendButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
// new SwingWorker<Void, Void>()
// {
// protected Void doInBackground() throws Exception
// {
// comm.setText("");
// sendMail();
// return null;
// }
// }.execute();
}
});
}

public void sendMail()
{
try
{
Socket s = new Socket(smtpServer.getText(), 25);

InputStream inStream = s.getInputStream();
OutputStream outStream = s.getOutputStream();

in = new Scanner(inStream);
out = new PrintWriter(outStream, true /* autoFlush */);

String hostName = InetAddress.getLocalHost().getHostName();

receive();
send("HELO " + hostName);
receive();
send("MAIL FROM: <" + from.getText() + ">");
receive();
send("RCPT TO: <" + to.getText() + ">");
receive();
send("DATA");
receive();
send(message.getText());
send(".");
receive();
s.close();
}
catch (IOException e)
{
comm.append("Error: " + e);
}
}

public void send(String s) throws IOException
{
comm.append(s);
comm.append("\n");
out.print(s.replaceAll("\n", "\r\n"));
out.print("\r\n");
out.flush();
}

public void receive() throws IOException
{
String line = in.nextLine();
comm.append(line);
comm.append("\n");
}

private Scanner in;
private PrintWriter out;
private JTextField from;
private JTextField to;
private JTextField smtpServer;
private JTextArea message;
private JTextArea comm;

public static final int DEFAULT_WIDTH = 300;
public static final int DEFAULT_HEIGHT = 300;
}


运行即出现效果图