boon/src/main/java/org/boon/Str.java
public static String underBarCase( String inStr ) {
        char[] in = FastStringUtils.toCharArray(inStr);
        char[] out = Chr.underBarCase( in );
        return FastStringUtils.noCopyStringFromChars( out );
    }
public static String underBarCase( String inStr ) {
        char[] in = FastStringUtils.toCharArray(inStr);
        char[] out = Chr.underBarCase( in );
        return FastStringUtils.noCopyStringFromChars( out );
    }
Convert to under bar case
@param inStr input string
@return new string