Code to Read E-Mail

• To compile and run, you must have mail.jar (from the JavaMail download) and activation.jar (from the JavaBeans Activation Framework download) in Java classpath.
• You need to replace mail server, username and password with your values where noted.
• This sample code has debugging turned on ("mail.debug") to see what is going on behind the scenes in JavaMail code.

  import java.util.*;
  import java.io.*;
  import javax.mail.*;
  import javax.mail.internet.*;
  import javax.mail.search.*;
  import javax.activation.*;
   
  
  public class FetchMailUsage {
  
      public static void main(String[] args) {
  
          // SUBSTITUTE YOUR ISP's POP3 SERVER HERE!!!
          String host = "pop.yourisp.net";
           // SUBSTITUTE YOUR USERNAME AND PASSWORD TO ACCESS E-MAIL HERE!!!
          String user = "your_username";
          String password = "your_password";
          // SUBSTITUTE YOUR SUBJECT SUBSTRING TO SEARCH HERE!!!
           String subjectSubstringToSearch = "Test E-Mail through Java";
  
          // Get a session.  Use a blank Properties object.
          Session session = Session.getInstance(new Properties());
   
          try {
  
              // Get a Store object
              Store store = session.getStore("pop3");
              store.connect(host, user, password);
  
              // Get "INBOX"
               Folder fldr = store.getFolder("INBOX");
              fldr.open(Folder.READ_WRITE);
              int count = fldr.getMessageCount();
              System.out.println(count  + " total messages");
   
              // Message numebers start at 1
              for(int i = 1; i <= count; i++) {
  								// Get  a message by its sequence number
                   Message m = fldr.getMessage(i);
  
                  // Get some headers
                  Date date = m.getSentDate();
                  Address [] from = m.getFrom();
                  String subj = m.getSubject();
                   String mimeType = m.getContentType();
                  System.out.println(date + "\t" + from[0] + "\t" +
                                      subj + "\t" + mimeType);
              }
   
              // Search for e-mails by some subject substring
              String pattern = subjectSubstringToSearch;
              SubjectTerm st = new SubjectTerm(pattern);
              // Get some message references
               Message [] found = fldr.search(st);
  
              System.out.println(found.length +
                                  " messages matched Subject pattern \"" +
                                  pattern + "\"");
   
              for (int i = 0; i < found.length; i++) {
                  Message m = found[i];
                  // Get some headers
                  Date date = m.getSentDate();
                  Address [] from = m.getFrom();
                   String subj = m.getSubject();
                  String mimeType = m.getContentType();
                  System.out.println(date + "\t" + from[0] + "\t" +
                                      subj + "\t" + mimeType);
   
                  Object o = m.getContent();
                  if (o instanceof String) {
                      System.out.println("**This is a String Message**");
                      System.out.println((String)o);
                   }
                  else if (o instanceof Multipart) {
                      System.out.print("**This is a Multipart Message.  ");
                      Multipart mp = (Multipart)o;
                       int count3 = mp.getCount();
                      System.out.println("It has " + count3 +
                          " BodyParts in it**");
                      for (int j = 0; j < count3; j++) {
                           // Part are numbered starting at 0
                          BodyPart b = mp.getBodyPart(j);
                          String mimeType2 = b.getContentType();
                           System.out.println( "BodyPart " + (j + 1) +
                                              " is of MimeType " + mimeType);
  
                          Object o2 = b.getContent();
                           if (o2 instanceof String) {
                              System.out.println("**This is a String BodyPart**");
                              System.out.println((String)o2);
                          }
                           else if (o2 instanceof Multipart) {
                              System.out.print(
                                  "**This BodyPart is a nested Multipart.  ");
                               Multipart mp2 = (Multipart)o2;
                              int count2 = mp2.getCount();
                              System.out.println("It has " + count2 +
                                  "further BodyParts in it**");
                           }
                          else if (o2 instanceof InputStream) {
                              System.out.println(
                                  "**This is an InputStream BodyPart**");
                           }
                      } //End of for
                  }
                  else if (o instanceof InputStream) {
                      System.out.println("**This is an InputStream message**");
                       InputStream is = (InputStream)o;
                      // Assumes character content (not binary images)
                      int c;
                      while ((c = is.read()) != -1) {
                          System.out.write(c);
                       }
                  }
  
                  // Uncomment to set "delete" flag on the message
                  //m.setFlag(Flags.Flag.DELETED,true);
  
              } //End of for
   
              // "true" actually deletes flagged messages from folder
              fldr.close(true);
              store.close();
  
          }
          catch (MessagingException mex) {
               // Prints all nested (chained) exceptions as well
              mex.printStackTrace();
          }
          catch (IOException ioex) {
              ioex.printStackTrace();
          }
  
      }
  
   
  } //End of class