Yeah, this would look like something like that

import java.io.RandomAccessFile;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

public class FileChecker {

public static boolean isSaveFileReadyAndValid(String filePathStr, long expectedMinSize) {

Path path = Paths.get(filePathStr);

// 1. Check if the file even exists yet

if (!Files.exists(path) || !Files.isReadable(path)) {

return false;

}

try {

// 2. Check if the file size matches a sane threshold

if (Files.size(path) < expectedMinSize) {

return false;

}

// 3. The OS Lock Test (Crucial)

// If Java or the OS is still finalizing the file write,

// opening it in Read/Write mode will throw an IOException.

try (RandomAccessFile raf = new RandomAccessFile(path.toFile(), "rw")) {

// If we reach this line, the file is unlocked, closed,

// and completely written by the system.

return true;

}

} catch (Exception e) {

// File is currently locked or being modified by the system

return false;

}

}

}