The isReadOnly() method of a FileStore class is used to return true if this file store is read-only else false. A file store is called read-only if it does not support write operations or other changes to files. An IOException to be thrown if an attempt to create a file, open an existing file for writing, etc occurs. Syntax:
public abstract String isReadOnly()
Parameters: This method accepts nothing. Return value: This method returns true if, and only if, this file store is read-only. Below programs illustrate the isReadOnly() method: Program 1:
Java
// Java program to demonstrate// FileStore.isReadOnly() methodimport java.io.IOException;import java.nio.file.FileStore;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;public class GFG { public static void main(String[] args) throws IOException { // create object of Path Path path = Paths.get( "E:\\Tutorials\\file.txt"); // get FileStore object FileStore fs = Files.getFileStore(path); // print FileStore name System.out.println("FileStore Name: " + fs.name()); // if file is readable boolean isReadOnly = fs.isReadOnly(); System.out.println("FileStore isReadOnly:" + isReadOnly); }} |
Output: 
Program 2:
Java
// Java program to demonstrate// FileStore.isReadOnly() methodimport java.io.IOException;import java.nio.file.FileStore;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;public class GFG { public static void main(String[] args) throws IOException { // create object of Path Path path = Paths.get( "C:\\Movies\092;048;01.txt"); // get FileStore object FileStore fs = Files.getFileStore(path); // print FileStore name System.out.println("FileStore Name: " + fs.name()); // if file is readable boolean isReadOnly = fs.isReadOnly(); System.out.println("FileStore isReadOnly:" + isReadOnly); }} |
Output: 
References: https://docs.oracle.com/javase/10/docs/api/java/nio/file/FileStore.html#isReadOnly()