Can JAXB output an ArrayList as comma separated values?

Question

I have something like

@XmlElementWrapper(name=\"Mylist\")
List myItems = new ArrayList()

and that comes out lik

Answer 1

Here's an XmlAdapter to handle comma separated lists:

import java.util.ArrayList;
import java.util.List;

import javax.xml.bind.annotation.adapters.XmlAdapter;

public class CommaSeparatedListAdapter extends XmlAdapter> {

    @Override
    public List unmarshal(final String string) {
        final List strings = new ArrayList();

        for (final String s : string.split(",")) {
            final String trimmed = s.trim();

            if (trimmed.length() > 0) {
                strings.add(trimmed);
            }
        }

        return strings;
    }

    @Override
    public String marshal(final List strings) {
        final StringBuilder sb = new StringBuilder();

        for (final String string : strings) {
            if (sb.length() > 0) {
                sb.append(", ");
            }

            sb.append(string);
        }

        return sb.toString();
    }
}

You would use it like this:

@XmlElementWrapper(name="Mylist")
@XmlJavaTypeAdapter(CommaSeparatedListAdapter.class)
List myItems = new ArrayList()