public static String replaceChars(String str, char searchChar, char replaceChar) {
      if (str == null) {
          return null;
      }
      return str.replace(searchChar, replaceChar);
  }
public static String replaceChars ( String str , char searchChar , char replaceChar ) { if ( str == null ) { return null ; } return str . replace ( searchChar , replaceChar ) ; }
<p>Replaces all occurrences of a character in a String with another.
This is a null-safe version of {@link String#replace(char, char)}.</p>

<p>A <code>null</code> string input returns <code>null</code>.
An empty ("") string input returns an empty string.</p>

<pre>
GosuStringUtil.replaceChars(null, *, *)        = null
GosuStringUtil.replaceChars("", *, *)          = ""
GosuStringUtil.replaceChars("abcba", 'b', 'y') = "aycya"
GosuStringUtil.replaceChars("abcba", 'z', 'y') = "abcba"
</pre>

@param str  String to replace characters in, may be null
@param searchChar  the character to search for, may be null
@param replaceChar  the character to replace, may be null
@return modified String, <code>null</code> if null string input
@since 2.0