java - 读取和写入同一文件 - 输出格式更改

Question

我想读取一个文件并根据某些条件将一些文本附加到同一个文件中。这是我的代码。

 public static void writeOutputToFile(ArrayList<String> matchingCriteria) {

    //Provide the folder which contains the files
    final File folder = new File("folder_location");
    ArrayList<String> writeToFile = new ArrayList<String>();

    //For each file in the folder
    for (final File fileEntry : folder.listFiles()) {

        try (BufferedReader br = new BufferedReader(new FileReader(fileEntry))) {
            String readLine = "";

            while ((readLine = br.readLine()) != null) {
                writeToFile.add(readLine);
            }

            try (FileWriter fw = new FileWriter(fileEntry); BufferedWriter bw = new BufferedWriter(fw)) {
                for (String s : writeToFile) {
                    boolean prefixValidation = false;
                    //Check whether each line contains one of the matching criterias. If so, set the condition to true
                    for (String y : matchingCriteria) {
                        if (matchingCriteria.contains(y)) {
                            prefixValidation = true;
                            break;
                        }
                    }
                    //Check if the prefixes available in the string
                    if (prefixValidation) {
                        if (s.contains("name=\"") && !(s.contains("id=\""))) {
                            //Split the filtered string by ' name=" '
                            String s1[] = s.split("name=\"");

                            /*Some Code*/                         
                            //Set the final output string to be written to the file
                            String output = "Output_By_Some_Code";

                            //Write the output to the file.
                            fw.write(output);

 //If this action has been performed, avoid duplicate entries to the file by  continuing the for loop instead of going through to the final steps
                                continue;
                            }
                        }
                        fw.write(s);
                        bw.newLine();
                    }             
                    fw.flush();
                    bw.flush();
 //Clear the arraylist which contains the current file data to store new file data.
                        writeToFile.clear();
                    }
                } catch (IOException ioe) {
                    ioe.printStackTrace();
                }
            }
    }

这段代码工作正常。问题是，输出与输入文件不完全相同。我附加一些内容的输入文件中的多行被写入输出文件中的同一行。

例如，我为这些元素添加了一个 id 属性，它被添加了，但输出被写成一行。

<input type="submit" <%=WebConstants.HTML_BTN_SUBMIT%> value="Submit" />
<input type="hidden" name="Page" value="<%=sAction%>" />
<input type="hidden" name="FileId" value="" />

我的问题是，我是不是做错了什么导致格式困惑？
如果是这样，是否可以按照输入文件进行打印？

非常感谢您的帮助。提前致谢:)

Answer 1

要解决您的问题，只需在您要编写的每一行中添加一个额外的行分隔符 (\n)。

所以这样:writeToFile.add(readLine); 变成这样:writeToFile.add(readLine+"\n");