On this document we will be showing a java example on how to use the setReadOnly() method of File Class. This method marks the file or directory named by this abstract pathname so that only read operations are allowed. After invoking this method the file or directory will not change until it is either deleted or marked to allow write access. On some platforms it may be possible to start the Java virtual machine with special privileges that allow it to modify files that are marked read-only. Whether or not a read-only file or directory may be deleted depends upon the underlying system.


  • SecurityException – If a security manager exists and its SecurityManager.checkWrite(java.lang.String) method denies write access to the named file.

Method Syntax

public boolean setReadOnly()

Method Argument

Data Type Parameter Description

Method Returns

This method returns boolean, true if and only if the operation succeeded; false otherwise.


Requires Java 1.2 and up

Java File setReadOnly() Example

Below is a java code demonstrates the use of setReadOnly() method of File class. The example presented might be simple however it shows the behaviour of the setReadOnly() method of File class.

Basically we set a file as readonly and we put a check if the operation succeeded or not.



 * This example source code demonstrates the use of  
 * setReadOnly() method of File class.

public class FileSetReadonlyExample {

	public static void main(String[] args) {
		// initialize File object
		File file = new File("C:javatutorialhqinputtest_file.txt");		
		// check first if file exist
			// set file as read only
			boolean result = file.setReadOnly();
			// evaluate the result
				System.out.println("Operation succeeded");
				System.out.println("Operation failed");
			System.out.println("File does not exist");

Sample Output

Below is the sample output when you run the above example.

java lang File setReadOnly() example output