Java - File setReadable(boolean readable) method



Description

The Java File setReadable(boolean readable) method is used to set or modify the read permission of a file. It returns true if the operation is successful, otherwise false.

  • If readable is true, the file is made readable.

  • If readable is false, the file is made not readable.

Declaration

Following is the declaration for java.io.File.setReadable(boolean readable) method −

public boolean setReadable(boolean readable)

Parameters

readable− true sets the access permission to allow read operations, false denies read operation.

Return Value

This method returns true if the operation succeeded, else false.

Exception

  • SecurityException − If a security manager exists and its method denies read access to the pathnames.

Example - Usage of File setReadable(boolean readable) method

The following example shows the usage of Java File setReadable(boolean readable) method. We've created a File reference. Then we're creating a File Object using a file path which is present in the given location. Using setReadable() method, we're trying to make the file readable and getting the result in boolean variable. Then we're printing the status of file as readable using canRead() method and result is printed.

FileDemo.java

package com.tutorialspoint;

import java.io.File;

public class FileDemo {
   public static void main(String[] args) {      
      File f = null;
      boolean bool = false;
      
      try {     
      
         // create new File objects
         f = new File("F:/test.txt");
         
         // set readable as true
         bool = f.setReadable(true);
         
         // prints
         System.out.println("setReadable() succeeded?: "+bool);
         
         // can read
         bool = f.canRead();
         
         // prints
         System.out.print("Can read?: "+bool);
         
      } catch(Exception e) {
         // if any error occurs
         e.printStackTrace();
      }
   }
}

Output

Let us compile and run the above program, this will produce the following result−

setReadable() succeeded?: true
Can read?: true

Example - Usage of File setReadable(boolean readable) method

The following example shows the usage of Java File setReadable(boolean readable) method. We've created a File reference. Then we're creating a File Object using a file path which is present in the given location and was made readable in previous example. Using setReadable() method, we're trying to make the file non-readable and getting the result in boolean variable. Then we're printing the status of file as readable using canRead() method and result is printed.

FileDemo.java

package com.tutorialspoint;

import java.io.File;

public class FileDemo {
   public static void main(String[] args) {      
      File f = null;
      boolean bool = false;
      
      try {     
      
         // create new File objects
         f = new File("F:/test.txt");
         
         // set readable as false
         bool = f.setReadable(false);
         
         // prints
         System.out.println("setReadable() succeeded?: "+bool);
         
         // can read
         bool = f.canRead();
         
         // prints
         System.out.print("Can read?: "+bool);
         
      } catch(Exception e) {
         // if any error occurs
         e.printStackTrace();
      }
   }
}

Output

Let us compile and run the above program, this will produce the following result−

setReadable() succeeded?: false
Can read?: true

Example - Setting Read Permission

The following example shows the usage of Java File setReadable(boolean readable) method.

FileDemo.java

package com.tutorialspoint;

import java.io.File;

public class FileDemo {
   public static void main(String[] args) {      
      // Create a File object representing an existing file
      File file = new File("example.txt");

      // Check if the file exists
      if (file.exists()) {
         // Set the file to be readable
         if (file.setReadable(true)) {
            System.out.println("File is now readable: " + file.getAbsolutePath());
         } else {
            System.out.println("Failed to set the file as readable.");
         }

         // Make the file non-readable
         if (file.setReadable(false)) {
            System.out.println("File is now NOT readable.");
         } else {
            System.out.println("Failed to remove read permission.");
         }
      } else {
         System.out.println("File does not exist.");
      }
   }
}

Possible Output

Let us compile and run the above program, this will produce the following result−

File is now readable: C:\Users\YourName\example.txt
File is now NOT readable.

Explanation

  • The program creates a File object for "example.txt".

  • It first checks if the file exists before modifying its permissions.

  • It calls setReadable(true) to grant read permission.

  • It then calls setReadable(false) to remove read permission.

  • The program prints messages indicating whether the operations were successful.

java_io_file_methods.htm
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