输入文本到file.txt的，无需更换时，在环

Question

我使用的缓冲笔者尝试输入文本到记事本，这是我来什么码了文本，

import java.util.Scanner; 
import java.io.*; 
public class FileSample { 
    public static void main (String[] args) { 
    Scanner sc = new Scanner(System.in); 
    String yourtext = " "; 
    String fn = "file.txt"; 
    String choice = " "; 
    do{ 
    try{ 
     FileWriter fw = new FileWriter(fn); 
     BufferedWriter bw = new BufferedWriter(fw); 
     System.out.print("Enter text: "); 
     yourtext = sc.nextLine(); 
     bw.write(yourtext); 
     bw.newLine(); 

     bw.close(); 
     System.out.println("==================================="); 
     System.out.print("Do you still want to continue?:\n [Y]Yes \n [N]No 
     \n::"); 
     choice = sc.nextLine(); 
    }catch(IOException ex){ 
     System.out.println("Error writing to file '" + fn + "'"); 
    } 
    }while(choice.equalsIgnoreCase("Y")); 


} 
} 

所以问题是当用户想要继续并再次输入文本并完成该过程时，应该在file.txt中的文本被新输入的文本替换。

Answer 1

只需添加FileWriter(fn,true)这将保留现有内容并将新内容附加到文件末尾。

Answer 2

你的问题是，你只是在覆盖模式下打开fileWriter，以使其只需将新文本附加到现有文件，只需将new FileWriter(fn)替换为FileWriter(fn,true)即可解决该问题。

但是，我也注意到，你的排序处理不当的资源（在我看来），所以我建议你一旦打开流/读/写，并在年底关闭它们：

public static void main(String[] args) { 
    String yourtext = " "; 
    String fn = "file.txt"; 
    String choice = " "; 
    try (Scanner sc = new Scanner(System.in); 
      FileWriter fw = new FileWriter(fn);   // making sure to free resources after using them 
      BufferedWriter bw = new BufferedWriter(fw);) { 
     do { 
      System.out.print("Enter text: "); 
      yourtext = sc.nextLine(); 
      bw.write(yourtext); 
      bw.newLine(); 
      System.out.println("==================================="); 
      System.out.print("Do you still want to continue?:\n [Y]Yes \n [N]No \n::"); 
      choice = sc.nextLine(); 
     } while (choice.equalsIgnoreCase("Y")); 
    } catch (IOException ex) { 
     System.out.println("Error writing to file '" + fn + "'"); 
    } 
}