Question

我使用的函数oldFile.delete（）和newfile.rename（“oldFile.txt”）都是文件对象，但这不起作用，删除函数和重命名函数给出错误，源代码如下：

      package urlFiltering;

      import java.io.*;
      import java.net.InetAddress;

      public class mainForm{


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

    String hostName="www.stackoverflow.com";

        InetAddress inetAddress=InetAddress.getByName(hostName);
                   String host=inetAddress.toString();
     FileReader inputFile = new FileReader("StoredIp.txt");
     File tempFile= new File("tempFile.txt");
            BufferedReader bufferReader = new BufferedReader(inputFile);
            String line;
            while ((line = bufferReader.readLine()) != null)   {
                    if(host.equals(line))
                            continue;
                      else
                            {
                                if (!tempFile.exists()) {
                                    tempFile.createNewFile();
                                }
                                FileWriter fw = new FileWriter(tempFile,true);
                                BufferedWriter bw = new BufferedWriter(fw);
                                bw.write(line);
                                bw.newLine();
                                bw.close();
                            }                                 
                    }

                bufferReader.close();  
                inputFile.delete();//error
                tempFile.renameTo("StoredIp.txt"); //error

       }
    }

Answer 1

您的inputFile是FileReader，没有delete()方法。您可以创建一个File对象来表示该文件，并将File作为FileReader构造函数的输入。然后，您还可以在最后delete()对象上调用File方法，而不是FileReader。 renameTo()会给您一个错误，因为该方法需要File而不是String。请改为renameTo(new File("StoredIp.txt"))。换句话说，这个：

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.net.InetAddress;

public class mainForm {

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

    String hostName = "www.stackoverflow.com";

    InetAddress inetAddress = InetAddress.getByName(hostName);
    String host = inetAddress.toString();
    File inputF = new File("StoredIp.txt");
    FileReader inputFile = new FileReader(inputF);
    File tempFile = new File("tempFile.txt");
    BufferedReader bufferReader = new BufferedReader(inputFile);
    String line;
    while ((line = bufferReader.readLine()) != null) {
        if (host.equals(line))
            continue;
        else {
            if (!tempFile.exists()) {
                tempFile.createNewFile();
            }
            FileWriter fw = new FileWriter(tempFile, true);
            BufferedWriter bw = new BufferedWriter(fw);
            bw.write(line);
            bw.newLine();
            bw.close();
        }
    }

    bufferReader.close();
    inputF.delete();// no more error
    tempFile.renameTo(new File("StoredIp.txt")); // no more error

}
}

编译错误：在java中删除和重命名文件？

1 个答案: