Java Cookbook

Providing Mail Settings

Problem

You want a way to automatically provide server host, protocol, user, and password.

Solution

Use a Properties object.

Discussion

You may remember from Section 7.8 that java.util.Properties is a list of name/value pairs, and that my FileProperties extends Properties to provide loading and saving. In several places in this chapter, I use a FileProperties object to preload a large variety of settings, instead of hardcoding them or having to type them all on the command line. When dealing with JavaMail, you must specify the mail hostname, username and password, protocol to use (IMAP, POP, or mailbox for reading), and so on. I store this information in a properties file, and most of the programs in this chapter will use it. Here is my default file, MailClient.properties :

# This file contains my default Mail properties.
# 
# Values for sending
Mail.address=[e-mail]
Mail.send.proto=smtp
Mail.send.host=localhost
Mail.send.debug=true
#
# Values for receiving
Mail.receive.host=localhost
Mail.receive.protocol=mbox
Mail.receive.user=*
Mail.receive.pass=*
Mail.receive.root=/var/mail/ian

The last two, pass and root, can have certain predefined values. Since nobody concerned with security would store unencrypted passwords in a file on disk, I allow you to set pass=ASK (in uppercase), which causes some of my programs to prompt for a password. The JavaMail API allows use of root=INBOX to mean the default storage location for your mail.

The keys in this list of ...