This article demonstrates how to detect whether an Excel document is password protected or not using Spire.XLS for Java.
import com.spire.xls.Workbook;
public class DetectProtectedOrNot {
public static void main(String[] args) {
//Get the file path
String filePath= "C:\\Users\\Administrator\\Desktop\\sample.xlsx";
//Detect whether the workbook is password protected or not
Boolean isProtected = Workbook.bookIsPasswordProtected(filePath);
//Print results
if (isProtected) {
System.out.print("The document is password protected.");
}
else {
System.out.print("The document is not protected.");
}
}
}

