如何从Unicode字符串中删除其他符号块

Question

I want to remove miscellaneous symbols block from Unicode string using regular expression may also try but none of them regular expression I think current can anyone help me for this issue how I can remove miscellaneous symbols block from the string.

Unicode String

\u263A\uD83D\uDE0A\uD83D\uDE22)\uD83C\uDF82

Code:

String input = "\u263A\uD83D\uDE0A\uD83D\uDE22)\uD83C\uDF82";
input.replaceAll("[\u2600-\u26FF]|[\u2700-\u27BF]", "");

Expected:

\uD83D\uDE0A\uD83D\uDE22)\uD83C\uDF82

but it will be not working how I can solve this issue.

Answer 1

It not work because String is immutable in Java you have to use assign the result to the input like this :

String result = input.replaceAll("[\u2600-\u26FF]|[\u2700-\u27BF]", "");

Or simply :

input = input.replaceAll("[\u2600-\u26FF]|[\u2700-\u27BF]", "");

So if you make a print like this :

System.out.println(input);
System.out.println("\uD83D\uDE0A\uD83D\uDE22)\uD83C\uDF82");

Both gives :

😊😢)🎂
😊😢)🎂

Answer 2

If the Input text contains u-escaped characters, as text consisting out of a backslash, 'u' and 4 hexadecimal Digits, convert them first to real char s.

input = StringEscapeUtils.unescapeJava(Input); // From Apache commons
input = input.replaceAll("[\u2600-\u26FF]|[\u2700-\u27BF]", "");