java查询结果以数组形式返回

代码比较简单
请多多指教

/**
	 * 查询结果以数组形式返回
	 * 
	 * @param sql 查询的sql语句
	 * @return
	 */
	public String[][] query(String sql){
		ConnectionPool pool = ConnectionPool.getInstance();  // 连接池

		ResultSet rs = null;
		String[][] result = null;
		
		Connection conn = pool.getConnection();
		try {
			rs = conn.createStatement().executeQuery(sql);
			ResultSetMetaData metadata = rs.getMetaData();
			
			int columnCount = metadata.getColumnCount();
			
			rs.last(); //移到最后一行
			int length = rs.getRow(); //得到当前行号，也就是记录数
			rs.beforeFirst(); //还要
			
			result = new String[length][columnCount];
			int index = 0;
			
			while(rs.next()){
				for(int i=0; i<columnCount; i++){
					result[index][i] = rs.getString(i+1);
				}
				index++;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}finally{
			closeRs(rs);
			pool.release(conn);
		}
		return result;
	}