Handlebars helper "concat" in JavaScript and Java

concat.js

module.exports = function () {
    var args = Array.prototype.slice.call(arguments, 0, arguments.length - 1);
    return args.join('');
};

ConcatHelper.java

import com.github.jknack.handlebars.Helper;
import com.github.jknack.handlebars.Options;

import java.io.IOException;
import java.util.StringJoiner;

public class ConcatHelper implements Helper<Object> {
    @Override
    public Object apply(Object firstObjectToConcat, Options options) throws IOException {
        StringJoiner joiner = new StringJoiner("");
        joiner.add(String.valueOf(firstObjectToConcat));
        
        // all params except the first one
        for (Object param : options.params) {
            joiner.add(String.valueOf(param));
        }
        return joiner.toString();
    }
}