Networking - Java Examples in a Nutshell - page 88

Example 5•3: SendMail.java (continued)
if (args.length >= 1)
System.getProperties().put("mail.host", args[0]);
// A Reader stream to read from the console
BufferedReader in =
new BufferedReader(new InputStreamReader(System.in));
// Ask the user for the from, to, and subject lines
System.out.print("From: ");
String from = in.readLine();
System.out.print("To: ");
String to = in.readLine();
System.out.print("Subject: ");
String subject = in.readLine();
// Establish a network connection for sending mail
URL u = new URL("mailto:" + to); // Create a mailto: URL
URLConnection c = u.openConnection(); // Create its URLConnection
c.setDoInput(false); // Specify no input from it
c.setDoOutput(true); // Specify we'll do output
System.out.println("Connecting..."); // Tell the user
System.out.flush(); // Tell them right now
c.connect(); // Connect to mail host
PrintWriter out = // Get output stream to host
new PrintWriter(new OutputStreamWriter(c.getOutputStream()));
// Write out mail headers. Don't let users fake the From address
out.print("From: \"" + from + "\" <" +
System.getProperty("user.name") + "@" +
InetAddress.getLocalHost().getHostName() + ">\n");
out.print("To: " + to + "\n");
out.print("Subject: " + subject + "\n");
out.print("\n"); // blank line to end the list of headers
// Now ask the user to enter the body of the message
System.out.println("Enter the message. " +
"End with a '.' on a line by itself.");
// Read message line by line and send it out.
String line;
for(;;) {
line = in.readLine();
if ((line == null) || line.equals(".")) break;
out.print(line + "\n");
}
// Close (and flush) the stream to terminate the message
out.close();
// Tell the user it was successfully sent.
System.out.println("Message sent.");
}
catch (Exception e) { // Handle any exceptions, print error message.
System.err.println(e);
System.err.println("Usage: java SendMail [<mailhost>]");
}
}
}