Java：CSV文件读取&写 [英] Java: CSV file read & write

问题描述

我正在读2个csv文件： store_inventory & new_acquisitions 。

我想能够将 store_inventory csv文件与 new_acquisitions 。
1）如果项目名称匹配，只需更新store_inventory中的数量。
2）如果new_acquisitions有一个在 store_inventory 中不存在的新项目，则将它添加到 store_inventory 。

I'm reading 2 csv files: store_inventory & new_acquisitions.
I want to be able to compare the store_inventory csv file with new_acquisitions. 1) If the item names match just update the quantity in store_inventory. 2) If new_acquisitions has a new item that does not exist in store_inventory, then add it to the store_inventory.

这是我到目前为止做的，但不是很好。我添加了评论，我需要添加taks 1 & 2 。

执行上述任务的任何建议或代码将是非常好的！感谢。

Here is what i have done so far but its not very good. I added comments where i need to add taks 1 & 2.
Any advice or code to do the above tasks would be great! thanks.

    File new_acq = new File("/src/test/new_acquisitions.csv");
    Scanner acq_scan = null;
    try {
        acq_scan = new Scanner(new_acq);
    } catch (FileNotFoundException ex) {
        Logger.getLogger(mainpage.class.getName()).log(Level.SEVERE, null, ex);
    }
    String itemName;
    int quantity;
    Double cost;
    Double price;

    File store_inv = new File("/src/test/store_inventory.csv");
    Scanner invscan = null;
    try {
        invscan = new Scanner(store_inv);
    } catch (FileNotFoundException ex) {
        Logger.getLogger(mainpage.class.getName()).log(Level.SEVERE, null, ex);
    }
    String itemNameInv;
    int quantityInv;
    Double costInv;
    Double priceInv;


    while (acq_scan.hasNext()) {
        String line = acq_scan.nextLine();
        if (line.charAt(0) == '#') {
            continue;
        }
        String[] split = line.split(",");

        itemName = split[0];
        quantity = Integer.parseInt(split[1]);
        cost = Double.parseDouble(split[2]);
        price = Double.parseDouble(split[3]);


        while(invscan.hasNext()) {
            String line2 = invscan.nextLine();
            if (line2.charAt(0) == '#') {
                continue;
            }
            String[] split2 = line2.split(",");

            itemNameInv = split2[0];
            quantityInv = Integer.parseInt(split2[1]);
            costInv = Double.parseDouble(split2[2]);
            priceInv = Double.parseDouble(split2[3]);


            if(itemName == itemNameInv) {
                //update quantity

            }
        }
        //add new entry into csv file

     }

再次感谢任何帮助。 =]

Thanks again for any help. =]

推荐答案

建议您使用现有的CSV解析器之一，例如 Commons CSV 或超级CSV ，而不是重新发明轮子。应该让你的生活更容易。

Suggest you use one of the existing CSV parser such as Commons CSV or Super CSV instead of reinventing the wheel. Should make your life a lot easier.

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