emoji.java

    private InputFilter mEmojiFilter = (source, start, end, dest, dstart, dend) -> {
        if (source.length() == 0) {
            return source;
        }
        // 入力された1文字が2バイト以上の物について、絵文字かどうか判断をする。
        // UTF-8 の絵文字の文字コードについては、 Wikipedia を参照した
        // https://en.wikipedia.org/wiki/Emoji#Unicode_blocks
        final int codePoint = Character.codePointAt(source, 0);
        if (
                (codePoint >= 0x1F300 && codePoint <= 0x1F5FF ) ||
                (codePoint >= 0x1F900 && codePoint <= 0x1F9FF ) ||
                (codePoint >= 0x1F600 && codePoint <= 0x1F64F ) ||
                (codePoint >= 0x1F680 && codePoint <= 0x1F6FF ) ||
                (codePoint >= 0x2600 && codePoint <= 0x26FF ) ||
                (codePoint >= 0x2700 && codePoint <= 0x27BF )
                ){
            return "";
        }
        return source;
    };