How to make a file read-only?

问题描述 (Problem Description)

如何将文件设为只读？

解决方案 (Solution)

此示例演示如何使用File类的file.setReadOnly（）和file.canWrite（）方法将文件设置为只读。

import java.io.File;
public class Main {
   public static void main(String[] args) {
      File file = new File("C:/java.txt");
      System.out.println(file.setReadOnly());
      System.out.println(file.canWrite());
   }
}

结果 (Result)

上面的代码示例将产生以下结果。要测试该示例，首先在'C'驱动器中创建一个文件'java.txt'。

true
false

以下是java中只读文件的另一个示例示例

import java.io.File;
import java.io.IOException;
public class FileReadAttribute { 
   public static void main(String[] args) throws IOException { 
      File file = new File("c:/file.txt");
      file.setReadOnly();
      if(file.canWrite()) {
         System.out.println("This file is writable");
      } else {
         System.out.println("This file is read only"); 
      } 
      file.setWritable(true);
      if(file.canWrite()) {
         System.out.println("This file is writable");
      } else {
         System.out.println("This file is read only");
      }
   }
}

上面的代码示例将产生以下结果。要测试该示例，首先在'C'驱动器中创建一个文件'java.txt'。

This file is read only
This file is read only