java转换emoji表情

/**
* @Description 将字符串中的emoji表情转换成可以在utf-8字符集数据库中保存的格式（表情占4个字节，需要utf8mb4字符集）
* @param str
* 待转换字符串
* @return 转换后字符串
* @throws UnsupportedEncodingException
* exception
*/
public static String emojiConvert1(String str)
throws UnsupportedEncodingException {
String patternString = "([\x{10000}-\x{10ffff}ud800-udfff])";

Pattern pattern = Pattern.compile(patternString);
Matcher matcher = pattern.matcher(str);
StringBuffer sb = new StringBuffer();
while(matcher.find()) {
try {
matcher.appendReplacement(
sb,
"[["
+ URLEncoder.encode(matcher.group(1),
"UTF-8") + "]]");
} catch(UnsupportedEncodingException e) {
LOG.error("emojiConvert error", e);
throw e;
}
}
matcher.appendTail(sb);
LOG.debug("emojiConvert " + str + " to " + sb.toString()
+ ", len：" + sb.length());
return sb.toString();
}

/**
* @Description 还原utf8数据库中保存的含转换后emoji表情的字符串
* @param str
* 转换后的字符串
* @return 转换前的字符串
* @throws UnsupportedEncodingException
* exception
*/
public static String emojiRecovery2(String str)
throws UnsupportedEncodingException {
String patternString = "\[\[(.*?)\]\]";

Pattern pattern = Pattern.compile(patternString);
Matcher matcher = pattern.matcher(str);

StringBuffer sb = new StringBuffer();
while(matcher.find()) {
try {
matcher.appendReplacement(sb,
URLDecoder.decode(matcher.group(1), "UTF-8"));
} catch(UnsupportedEncodingException e) {
LOG.error("emojiRecovery error", e);
throw e;
}
}
matcher.appendTail(sb);
LOG.debug("emojiRecovery " + str + " to " + sb.toString());
return sb.toString();
}