Question

我知道有很多与此相关的问题，但是我仍然没有遵循。我已从有关如何创建，写入和读取文件的教程中复制了以下代码。有一个CreateFile类，一个ReadFile类和一个Demo类：

CreateFile.java

import java.io.*;
import java.lang.*;
import java.util.*;

public class CreateFile {
    private Formatter x;

    public void openFile(){
        try{
            x = new Formatter("chinese.txt");
        }
        catch(Exception e)
        {
            System.out.println("You have an error");
        }
    }

    public void addRecords(){
        x .format("%s%s%s", "20 ", "bucky ", "robers");
    }

    public void closeFile(){
        x.close();
    }
}

ReadFile.java

public class ReadFile {
    private Scanner x;

    public void openFile()
    {
        try{
            x = new Scanner(new File("words.txt"));
        }
        catch(Exception e){
            System.out.println("could not find file");
        }
    }

    public void readFile()
    {
        while(x.hasNext()) 
        {
            String a = x.next();
            String b = x.next();
            String c = x.next();

            System.out.printf("%s %s %s\n", a,b,c);
        }
    }
    public void closeFile()
    {
        x.close();
    }

}


public class Demo {

    public static void main(String[] args) {
        CreateFile g = new CreateFile();
        g.openFile();
        g.addRecords();
        g.closeFile();

        WordCounter r = new WordCounter();
        r.openFile();
        r.readFile();
        r.closeFile();
    }

在Demo.java中，如果我删除了与读取文件有关的后四个语句，则与打开和写入文件有关的前四个语句将正常运行。但是，一旦我添加

WordCounter r = new WordCounter();
r.openFile();
r.readFile();
r.closeFile();

并运行程序，它输出：Exception in thread "main" could not find file.我不确定发生了什么，文件chinese.txt从未被创建吗？

Answer 1

我建议您研究序列化比写.txt文件容易得多。

但是，如果您确实需要处理.txt文件，这就是您写入.txt文件的方式

    //This gets your project directory
    private String projectPath = System.getProperty("user.dir");
    //call save()
    String save("test.txt", "This is will be save to a test.txt file");

    private boolean save(String textfile String outputtext){
        String filepath = projectPath + textfile;

        try{
            BufferedWriter writer = new BufferedWriter(new FileWriter(filepath));
            writer.write(outputtext);
            writer.close();
        } catch(IOException e) { }

        return true;
    }

这就是你的阅读方式

    private String load(String textfile){
        String temp="";
        String filepath = projectPath + textfile;
        try{
            BufferedReader reader =new BufferedReader(new FileReader(filepath));
            while(true){
                //this will read one line at a time you can append it output
                try {
                    temp+= reader.readLine();
                    //If no more lines break out of the loop
                    if(line==null)
                        break;

                }catch(IOException e){}
            }
            reader.close();
        }
        catch(IOException e){}
        //Return contents of the file you loaded
        return temp;
    }

我希望这段代码足够清楚。如果您还有其他问题，请告诉我。我会很乐意回答他们。

创建，写入和读取文件

1 个答案: