Java-replaceall usage

the replaceAll () method uses the given parameters replacement replacement string matches all given regular expression substring.

String replaceAll public (String regex, String Replacement) 

regex ---- This string matches regular expression 
newChar ---- to replace every occurrence of a string of 

successful replacement string is returned, failed to return the original string.

String str = "1234*Aa";
System.out.println(str.replaceAll("\\*", "6"));

Output:

12346Aa

String str = "1234*Aa";
System.out.println(str.replaceAll("(\\*)+", "zx"));

Output:

1234zxAa