Gmail APIs: Decoding the body of the message (Java/Android)

Question

I need to get the retrieved mail in the format it was in the user mailbox, i.e.: HTML.
I am having troubles decoding the body of the retrieved message.

Please suggest a method for getting this done in Java.

I am currently doing this to get the message:

public class MyClass {

  public static Message getMessage(Gmail service, String userId, String messageId)
      throws IOException {
    Message message = service.users().messages().get(userId, messageId).execute();

    System.out.println("Message snippet: " + message.getSnippet());

    return message;
  }

  public static MimeMessage getMimeMessage(Gmail service, String userId, String messageId)
      throws IOException, MessagingException {
    Message message = service.users().messages().get(userId, messageId).setFormat("raw").execute();

    byte[] emailBytes = Base64.decodeBase64(message.getRaw());

    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);

    MimeMessage email = new MimeMessage(session, new ByteArrayInputStream(emailBytes));

    return email;
  }

}

What exactly is the problem with that code? Does it crash, return an error, return garbled data, or what? — Ken Y-N, Apr 10 '15 at 05:26
When I execute that code with the message ID, I get the following in the body: http://pastebin.com/LKH6V3kV — Ayush Gupta, Apr 10 '15 at 05:39
Does [this question help](http://stackoverflow.com/questions/24812139/base64-decoding-of-mime-email-not-working-gmail-api)? — Ken Y-N, Apr 10 '15 at 05:40

score 5 · Accepted Answer · answered Apr 15 '15 at 06:38

5

String mimeType = message.getPayload().getMimeType();
    List<MessagePart> parts = message.getPayload().getParts();
    if (mimeType.contains("alternative")) {
        log.info("entering alternative loop");
        for (MessagePart part : parts) {
            mailBody = new String(Base64.decodeBase64(part.getBody()
                    .getData().getBytes()));

        }
        log.info(mailBody);
    }

answered Apr 15 '15 at 06:38

Kiran Palaka

86
3

This answer really helped me solve an issue I was stuck on for 4-5 hours !! thanks @Kiran Palaka – Dinesh Oct 23 '16 at 22:54
Help, Im getting a nullpointer in "part.getBody().getData()" because "part.getBody()" returns an array of DataMap$Entry – Pedro Joaquín Oct 09 '20 at 14:57
Unfortunately, I get an error `the return value of "com.google.api.services.gmail.model.Message.getPayload()" is null` – Zoette Aug 30 '22 at 03:34

score 1 · Answer 2 · answered Aug 08 '16 at 12:15

You could use the following methods:

private String getContent(Message message) {
    StringBuilder stringBuilder = new StringBuilder();
    try {
        getPlainTextFromMessageParts(message.getPayload().getParts(), stringBuilder);
        byte[] bodyBytes = Base64.decodeBase64(stringBuilder.toString());
        String text = new String(bodyBytes, "UTF-8");
        return text;
    } catch (UnsupportedEncodingException e) {
        logger.error("UnsupportedEncoding: " + e.toString());
        return message.getSnippet();
    }
}

private void getPlainTextFromMessageParts(List<MessagePart> messageParts, StringBuilder stringBuilder) {
    for (MessagePart messagePart : messageParts) {
        if (messagePart.getMimeType().equals("text/plain")) {
            stringBuilder.append(messagePart.getBody().getData());
        }

        if (messagePart.getParts() != null) {
            getPlainTextFromMessageParts(messagePart.getParts(), stringBuilder);
        }
    }
}

It combines all message parts with the mimeType "text/plain" and returns it as one string.

score -1 · Answer 3 · answered Jun 04 '19 at 20:55

-1

new String(messageResult.getPayload().getParts().get(0).getBody().decodeData())

answered Jun 04 '19 at 20:55

Yunier Broche Guevara

189
2
11

Gmail APIs: Decoding the body of the message (Java/Android)

3 Answers3