Java emoji conversion to xml: what libraries exist?

Question

I am transforming MIME messages to XML so that I can submit them to a mail merge service as SOAP requests, but Emoji are giving me problems (the smiley 😃 for example, which I'd like to have converted to 😃).

I'm using XStream to handle my conversions but it doesn't properly encode emoji and other high/low surrogate pairs (see the example test case below). It is possible that I am missing some crucial xstream configuration component.

I have found this project that is based on this project which does conversions for specific Japanese cell phone providers via a hard-coded mapping, but I feel like this problem is probably solved more elegantly in existing Oracle or third-party (Apache, etc.) libraries.

From what I've read and heard NuSOAP addresses this issue for PHP but I'd like to stay in the Java/Groovy world for emoji conversion so I can use a compatible library.

What tools/approaches are you using to handle emoji conversion to XML on the JVM?

import junit.framework.TestCase;
import com.thoughtworks.xstream.XStream;

public class XStreamTest extends TestCase {
    public void testXStreamEmojiEncoding() {
        final String expected = "Open mouth smiley 😃 and two chicken heads followed by a period 🐔🐔.";
        final String original = "Open mouth smiley 😃 and two chicken heads followed by a period 🐔🐔.";

        final XStream xStream = new XStream();

        final String returned = xStream.toXML(original);

        assertEquals("<string>" + expected + "</string>", returned);
    }
}

The above test looks for an HTML decimal representation of the emoji but I'll accept other formats that will work for MIME.

Answer 1

I recently wrote a library for this: emoji-java
Here is the kind of output you would get:

String str = "An 😀awesome 😃string with a few 😉emojis!";
String result = EmojiParser.parseToAliases(myString);
System.out.println(myString);
// Prints:
// "An 😀awesome 😃string with a few 😉emojis!"

You can either add the jar to your project or use the maven dependency:

<dependency>
  <groupId>com.vdurmont<groupId>
  <artifactId>emoji-java<artifactId>
  <version>1.0.0</version> <!-- Or whatever the version will be when you read this post -->
</dependency>