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  • list add对象踩的坑

    list 添加对象时,没有把new object写到循环体里,导致最后添加了相同的一个对象;

    public List<goods> find(String goodsname) {
    		List<goods>list = new ArrayList<goods>() ;
    		
    		PreparedStatement pstmt = null;
    		ResultSet rs = null;
    		String sql = "select * from goods where goods_name=?";
    		try {
    			int i=0;
    			pstmt = (PreparedStatement) c.prepareStatement(sql);
    			pstmt.setString(1, goodsname);
    			rs = (ResultSet) pstmt.executeQuery();
    			while (rs.next()) {
    				goods = new goods();
    				goods.setGoods_id(rs.getString(1));
    				goods.setGoods_name(rs.getString(2));
    				goods.setGoods_sum(rs.getString(3));
    				goods.setGoods_price(rs.getString(4));
    				goods.setGoods_from(rs.getString(5));
    				goods.setGoods_time(rs.getString(6));
    			
    				list.add(i++, goods);
    						 
    			}
    		 
    			
    			return list;
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		return null;
    	}
    
    其中 goods = new goods();一定要放到循环体里面。
    
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  • 原文地址:https://www.cnblogs.com/zhaocundang/p/10098441.html
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