@Override
    public List<String> getTableNames(String tableSchema) {
        DatabaseMetaData metaData = null;
        List<String> tables = new ArrayList<String>();
        ResultSet rs = null;
        try {
            metaData = conn.getMetaData();
            rs = metaData.getTables(conn.getCatalog(), null, "%", new String[]{"TABLE"});
            while (rs.next()) {
                tables.add(rs.getString("TABLE_NAME"));
            }

        } catch (SQLException e) {
            logger.error("[getTableNames Exception] --> "
                    + "the exception message is:" + e.getMessage());
        } finally {
            JdbcUtils.close(rs);
        }


        return tables;
    }
@Test
    public void getTableNames() {
        List<String> tableNames = queryTool.getTableNames(null);
        for (String table : tableNames) {
            System.out.println(table);
        }
    }