public class MyClass {
static String extract_only_pecial_characters(String s) {
int len = s.length();
String regx = "[a-zA-Z0-9\\s+]";
String pecial_characters = "";
for (int i = 0; i < len; i++) {
char ch = s.charAt(i);
if (!String.valueOf(ch).matches(regx))
pecial_characters = pecial_characters + ch;
}
return pecial_characters;
}
public static void main(String args[]) {
String s = "c++14$vb.net&%java*() php <>/python 3.7.3";
System.out.println(extract_only_pecial_characters(s));
}
}
/*
run:
$.&%*()<>/..
*/