Question

所以我写了这段代码，我想知道为什么我没有收到我想要的输出类型......

//Method to copy over a file to a new file using a delimiter and breaking up the file if it is more than 15 images
    public static void copyFile(File extractedInfo) 
    {
        try
        {
            //Counter to track the # of images/lines
            int c = 0;

            File inputFile = extractedInfo;
            File outputFile = new File(extractedInfo.getParentFile() + "/Extracted Info " + index2++ + ".txt");

            Scanner reader = new Scanner(inputFile);
            reader.useDelimiter("null(U) ");
            BufferedWriter writer = new BufferedWriter(new FileWriter(outputFile));

            //While there is a next line...
            while (reader.hasNextLine())
            {
                //If the document has 15 images, create a new file to write to
                if (c%15 == 0)
                {
                    writer.close();
                outputFile = new File(extractedInfo.getParentFile() + "/Extracted Info " + ((index2++) + 1) + ".txt");
                writer = new BufferedWriter(new FileWriter(outputFile));
                }
                //Else, normally, just write out each individual character from the original file.
                writer.append(reader.next());
                c++;
            }

            reader.close();
            writer.close();
        }
        catch (Exception e)
        {
            e.printStackTrace(System.out);
        }
    }

原始文件基本上看起来像......

C:\Documents and Settings\workspace\Extracted Items\image2.jpeg;image0;null(U) keyword1, keyword2, keyword3, keyword4,
C:\Documents and Settings\workspace\Extracted Items\image3.jpeg;image1;null(U) keyword1, keyword2, keyword3, keyword4,
C:\Documents and Settings\workspace\Extracted Items\image4.jpeg;image2;null(U) keyword1, keyword2, keyword3, keyword4,
C:\Documents and Settings\workspace\Extracted Items\image5.jpeg;image3;null(U) keyword1, keyword2, keyword3, keyword4,

问题是，输出文件看起来完全一样，但我想要复制所有内容除了原始文档中的“null（u）”字符串。我只是想知道，我的代码是否符合我的要求，我应该如何重新设置分隔符以忽略原始文件中的“null（U）”引用？

感谢任何提供的意见。

Answer 1

在循环中更改outputFile对writer没有影响，您还需要在相同的if中重新创建它（在重新分配后添加第二行）;在打开新作家之前关闭旧作家。

Answer 2

我还不确定你想要做什么，但行

        writer.append(reader.next());

似乎有一个缺陷。作者可能仍然引用原始outputFile而不是新文件。

所以，你可能需要这样做：

               if (c%15 == 0)
                {
                    outputFile = new File(extractedInfo.getParentFile() + "/Extracted Info " + ((index2++) + 1) + ".txt");
                    writer = new BufferedWriter(new FileWriter(outputFile));
                }

Answer 3

我以为我会发布这段代码，以防它可能对有类似问题的其他人有所帮助。

  //Method to copy over a file to a new file using a delimiter and breaking up the file if it is more than 15 images
        public static void copyFile(File extractedInfo) 
        {
            try
            {
                //Counter to track the # of images/lines
                int c = 0;

                File inputFile = extractedInfo;
                File outputFile = new File(extractedInfo.getParentFile() + "/Extracted Info " + index2 + ".txt");

                Scanner reader = new Scanner(inputFile);
                reader.useDelimiter("null\\(U\\) ");
                BufferedWriter writer = new BufferedWriter(new FileWriter(outputFile));

                //While there is a next line...
                while (reader.hasNextLine())
                {
                    //If the document has 15 images, create a new file to write to
                    if (c%15 == 0)
                    {
                        writer.close();
                        outputFile = new File(extractedInfo.getParentFile() + "/Extracted Info " + index2++ + ".txt");
                        writer = new BufferedWriter(new FileWriter(outputFile));

                        writer.append(reader.next());
                        c++;
                    }
                    else
                    {
                        //Else, normally, just write out each individual character from the original file.
                        writer.append(reader.next());
                        c++;
                    }
                }

                reader.close();
                writer.close();
            }
            catch (Exception e)
            {
                e.printStackTrace(System.out);
            }
        }

关于在Java中复制文本文件的问题

3 个答案: