private int lookAhead1(String sql, int index) {
        index++;
        if (index < sql.length()) {
            return sql.charAt(index);
        } else {
            return NEXT_TOKEN_NOT_EXIST;
        }
    }
look up the next character in a string

@param sql
@param index
@return
commons-profiler/src/main/java/com/navercorp/pinpoint/common/profiler/sql/DefaultSqlNormalizer.java