java - 如何使用 BufferedReader 在 java 中复制并写入文本文件

Question

我能够让我的 SUBMIT 文件夹正确地包含 3 个 .csv 文件，正确命名并包含正确的学生信息，但是当我尝试复制 SUBMIT 文件夹中每个 .csv 的第二行并打印到单个文本中时文件在 OUTPUT 文件夹中我在文件中得到以下输出:

COURSE ID,TEAM ID,STUDENT FIRST NAME,STUDENT LAST NAME,STUDENT ID,ASSIGNMENT ID,DATE SUBMITTED,TIME SUBMITTED,SUBMITTED BYCOURSE ID,TEAM ID,STUDENT FIRST NAME,STUDENT LAST NAME,STUDENT ID,ASSIGNMENT ID,DATE SUBMITTED,TIME SUBMITTED,SUBMITTED BY
CMPS280-01,00,Keith,Dillinger,w0782345,H01,8/25/2017,1:23AM,Keith Dillinger

我的代码是:

import java.io.*;

public class HW01 {
    public static void main(String args[]) throws IOException {

        // Create a 1D array to hold header labels
        String headerLabels[] =  
            {
             "COURSE ID", "TEAM ID", "STUDENT FIRST NAME",
             "STUDENT LAST NAME", "STUDENT ID", "ASSIGNMENT ID",
             "DATE SUBMITTED", "TIME SUBMITTED", "SUBMITTED BY"
            };

        // Create a 2D array to hold header values
        String headerValues[][] =
            {
            {"CMPS280-01", "03", "Jacob", "Harley", "w0389342", "H01", "8/23/2017", "7:24PM", "Jacob Harley"},
            {"CMPS280-01", "01", "James", "Brown", "w0479045", "H01", "8/25/2017", "1:14PM", "James Brown"},
            {"CMPS280-01", "00", "Keith", "Dillinger", "w0782345", "H01", "8/25/2017", "1:23AM", "Keith Dillinger"}
            };

        // Create string to change to next line of .csv file
        String newLine = "";

        // Loop to name .csv files
        for (int i = 0; i < headerValues.length; i++){

            // Create new .csv file and store in SUBMIT folder
            String submitPath = "SUBMIT/"+headerValues[i][0]+"_"+headerValues[i][5]+"_"+headerValues[i][1]+"_"+headerValues[i][4]+".csv";
                File submitFile = new File(submitPath);
                PrintWriter submitWriter = new PrintWriter(submitFile);

                // Print headerLabels to .csv files in SUBMIT folder
                for (int j = 0; j < headerValues[i].length; j++){
                    submitWriter.print(headerLabels[j]);
                    if (j < headerLabels.length-1)
                    submitWriter.print(",");
                }
                // Change to line 2 and write header
                submitWriter.println(newLine);
                for (int j = 0; j < headerValues[i].length; j++){
                    submitWriter.print(headerValues[i][j]);
                    if (j < headerValues[i].length-1)
                        submitWriter.print(",");
                }
            submitWriter.close();

            // Create new .csv file and store in OUTPUT folder
            String outputPath = "OUTPUT/"+"All_submit"+"_"+headerValues[0][0]+"_"+headerValues[0][5]+".csv";
                File outputFile = new File(outputPath);
                PrintWriter outputWriter = new PrintWriter(outputFile);

                // Print headerLabels to .csv file in OUTPUT folder
                for (int j = 0; j < headerValues[i].length; j++){
                    outputWriter.print(headerLabels[j]);
                    if (j < headerLabels.length-1)
                        outputWriter.print(",");
                }

                // Create an array of files to store all objects from SUBMIT folder
                File folder = new File("SUBMIT");
                File[] fileList = folder.listFiles();

                // Read information from the second line of all .csv files in SUBMIT folder
                for (File f : fileList){
                    FileReader reader = new FileReader(f);
                    BufferedReader br = new BufferedReader(reader);

                    String line;
                    while ((line = br.readLine()) != null){
                        outputWriter.println(line);
                            System.out.println(line);
                    }

                outputWriter.close();
                    reader.close();
                    br.close();
                }

        }

    }
 }

Answer 1

将标题行写入 OUTPUT 目录中的文件后，您将复制 SUBMIT 中相应文件中的所有行，包括其 标题行。看起来您不需要重新编写 OUTPUT 文件的标题行。或者，您可以在从 SUBMIT 文件复制时跳过标题行的写入。

顺便说一句，第二次编写标题行时，您缺少行终止符。