code: public static LexerEngine newInstance(final DatabaseType dbType, final String sql) {
          switch (dbType) {
              case H2:
                  return new LexerEngine(new H2Lexer(sql));
              case MySQL:
                  return new LexerEngine(new MySQLLexer(sql));
              case Oracle:
                  return new LexerEngine(new OracleLexer(sql));
              case SQLServer:
                  return new LexerEngine(new SQLServerLexer(sql));
              case PostgreSQL:
                  return new LexerEngine(new PostgreSQLLexer(sql));
              default:
                  throw new UnsupportedOperationException(String.format("Cannot support database [%s].", dbType));
          }
      }
docs: Create lexical analysis engine instance.
  
  @param dbType database type
  @param sql SQL
  @return lexical analysis engine instance