How do I retrieve all mails from email with java

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Java

Gmail

POP3

Hi everyone, hope you are doing well. I've tried to retrieve all mails from my Gmail INBOX but it's not working unfortunately. There is no error. It's just showing me i've no mail in that folder.

What I have tried:

public static void downloadEmailAttachments(String host, String port, String userName, String password) {
        try {
            //create properties field
            Properties properties = new Properties();

            properties.put("mail.pop3.host", host);
            properties.put("mail.pop3.port", (String)port);
            properties.put("mail.pop3.starttls.enable", "true");
            Session emailSession = Session.getDefaultInstance(properties);

            //create the POP3 store object and connect with the pop server
            Store store = emailSession.getStore("pop3");

            store.connect("pop.gmail.com", userName, password);

            // opens the inbox folder
            Folder folderInbox = store.getFolder("INBOX");
            folderInbox.open(Folder.READ_ONLY);
            for (Message m : folderInbox.getMessages()) {
                System.out.println(m);
            }

            // fetches new messages from server
            Message[] arrayMessages = folderInbox.getMessages();

            for (int i = 0; i < arrayMessages.length; i++) {
                Message message = arrayMessages[i];
                Address[] fromAddress = message.getFrom();
                String from = fromAddress[0].toString();
                String subject = message.getSubject();
                String sentDate = message.getSentDate().toString();

                String contentType = message.getContentType();
                String messageContent = "";

                // store attachment file name, separated by comma
                String attachFiles = "";

                if (contentType.contains("multipart")) {
                    // content may contain attachments
                    Multipart multiPart = (Multipart) message.getContent();
                    int numberOfParts = multiPart.getCount();
                    for (int partCount = 0; partCount < numberOfParts; partCount++) {
                        MimeBodyPart part = (MimeBodyPart) multiPart.getBodyPart(partCount);
                        if (Part.ATTACHMENT.equalsIgnoreCase(part.getDisposition())) {
                            // this part is attachment
                            String fileName = part.getFileName();
                            attachFiles += fileName + ", ";
                            part.saveFile(new File(fileName));
                        } else {
                            // this part may be the message content
                            messageContent = part.getContent().toString();
                        }
                    }

                    if (attachFiles.length() > 1) {
                        attachFiles = attachFiles.substring(0, attachFiles.length() - 2);
                    }
                } else if (contentType.contains("text/plain")
                        || contentType.contains("text/html")) {
                    Object content = message.getContent();
                    if (content != null) {
                        messageContent = content.toString();
                    }
                }

                // print out details of each message
                System.out.println("Message #" + (i + 1) + ":");
                System.out.println("\t From: " + from);
                System.out.println("\t Subject: " + subject);
                System.out.println("\t Sent Date: " + sentDate);
                System.out.println("\t Message: " + messageContent);
                System.out.println("\t Attachments: " + attachFiles);
            }

            // disconnect
            folderInbox.close(false);
            store.close();
        } catch (NoSuchProviderException ex) {
            System.out.println("No provider for pop3.");
            ex.printStackTrace();
        } catch (MessagingException ex) {
            System.out.println("Could not connect to the message store");
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }