Es1javax.mail.NoSuchProviderException: No provider for pop3 ?

Question

What is wrong with this code?Do i need to specify a Provider? Where and when?
String host = ...;
String username = ...;
String password = ...;
// Create empty properties
Properties props = new Properties();
// Get session
Session ses = Session.getDefaultInstance(props, null);
// Get the store
Store store = ses.getStore("pop3");
store.connect(host, username, password);
// Get folder
Folder folder = store.getFolder("INBOX");
folder.open(Folder.READ_ONLY);
// Get directory
Message message[] = folder.getMessages();
for (int i=0, n=message.length; i<n; i++) {
System.out.println(i + ": " + message.getFrom()[0]
+ "\t" + message[i].getSubject());
// Close connection
folder.close(false);
store.close();
Thank you all
Dena

Answer 1

[denapuerta],
The exception that you are getting may mean that the java runtime environment that you are running your class file code on does not seem to have the JavaMail .jar files installed correctly. The JavaMail API packages are optional packages and must be downloaded and added to the J2SE runtime environment before such an application can run successfully.
From the exception message, looks like either the pop3.jar file or the mailapi.jar (which contains all the JavaMail API and provider library files) is missing from the CLASSPATH of the JRE or not installed onto the <JRE install directory>/jre/lib/ext directory.
What is wrong with this code?Do i need to specify a
Provider? Where and when?I assume you obtained the code from the jGuru tutorial on JavaMail (which is a good tutorial to start off with). I have tested the code before and it works perfectly fine.
String host = ...;
String username = ...;
String password = ...;
// Create empty properties
Properties props = new Properties();
// Get session
Session ses = Session.getDefaultInstance(props, null);
// Get the store
Store store = ses.getStore("pop3");
store.connect(host, username, password);
// Get folder
Folder folder = store.getFolder("INBOX");
folder.open(Folder.READ_ONLY);
// Get directory
Message message[] = folder.getMessages();
for (int i=0, n=message.length; i<n; i++) {
System.out.println(i + ": " +
+ message.getFrom()[0]
+ "\t" + message[i].getSubject());
// Close connection
folder.close(false);
store.close();
Thank you all
Dena
You might also want to check the username/password and hostname string entries to see if you are really connecting to the POP3 mail server correctly.
HTH.
Allen Lai
Developer Technical Support
SUN Microsystems
http://www.sun.com/developers/support/