read all mails from gmail inbox using apache camel

问题

I am trying to read all mails from google mail (Gmail - imaps) account and download its attachments but I am only able to get one unread mail and its attachments.

Posting my code snippet.

// Download function 

public void  download() throws Exception {

        PollingConsumer pollingConsumer = null;
        CamelContext context = new DefaultCamelContext();

        Endpoint endpoint =
                context.getEndpoint("imaps://imap.gmail.com?username="
                        + mailId + "&password=" + password 
                        + "&delete=false&peek=false&unseen=true&consumer.delay=60000&closeFolder=false&disconnect=false");

        pollingConsumer = endpoint.createPollingConsumer();
        pollingConsumer.start();

        pollingConsumer.getEndpoint().createExchange();
        Exchange exchange = pollingConsumer.receive();

        log.info("exchange : " + exchange.getExchangeId());
        process(exchange);

}

// mail process function

public void process(Exchange exchange) throws Exception {
    Map<String, DataHandler> attachments = exchange.getIn().getAttachments();

    Message messageCopy = exchange.getIn().copy();

    if (messageCopy.getAttachments().size() > 0) {
        for (Map.Entry<String, DataHandler> entry : messageCopy.getAttachments().entrySet()) {
            DataHandler dHandler = entry.getValue();
            // get the file name
            String filename = dHandler.getName();

            // get the content and convert it to byte[]
            byte[] data =
                    exchange.getContext().getTypeConverter().convertTo(byte[].class, dHandler.getInputStream());

            FileOutputStream out = new FileOutputStream(filename);
            out.write(data);
            out.flush();
            out.close();
            log.info("Downloaded attachment, file name : " + filename);

        }
    }
}

Help me to iterate through all the mails(from inbox,unread).

回答1:

You need to run Exchange exchange = pollingConsumer.receive(); in a loop.

For e.g.

Exchange ex = pollingConsumer.receive();
while (ex != null) {
    process(ex);
    ex = pollingConsumer.receive();
}

来源：https://stackoverflow.com/questions/25763655/read-all-mails-from-gmail-inbox-using-apache-camel