Files CRUD

java.nio.file.Files and java.io.File handle file operations. CRUD = Create, Read, Update, Delete.

Files — create, read, update, delete

java.nio.file.Files and java.io.File handle file operations. CRUD = Create, Read, Update, Delete.

Always check if file exists before read. Handle IOException for missing files or permission errors.

Real-life example: Files CRUD is managing a notebook — write new page (create), read page (read), edit text (update), tear page (delete).

File CRUD with java.io.File

import java.io.File;
import java.io.IOException;

File file = new File("data.txt");

// Create
if (file.createNewFile()) {
    System.out.println("Created");
}

// Read exists?
System.out.println("Exists: " + file.exists());
System.out.println("Size: " + file.length());

// Delete
// file.delete();

Files utility class (NIO)

Files.write, Files.readString, Files.delete — modern shortcuts in Java 11+.

Paths.get("folder", "file.txt") builds cross-platform paths.

Real-life example: Files utility is express delivery — one method call instead of many manual steps.

Files.readString and write

import java.nio.file.*;

Path path = Paths.get("hello.txt");
Files.writeString(path, "Welcome to Java!");
String content = Files.readString(path);
System.out.println(content);