BAEL-9267: Determine If a File is a PDF File in Java

Author: manfred106

text-processing-libraries-modules/pdf-2/src/test/java/com/baeldung/detect/PdfDetectTest.java

@@ -49,7 +49,7 @@ void whenDetectPdfByFileSignature_thenCorrect() throws IOException {
         boolean isPdf = false;
         try (InputStream fis = new BufferedInputStream(new FileInputStream(PDF_FILE))) {
             byte[] bytes = new byte[5];
-            if (fis.read(bytes) >= 5) {
+            if (fis.read(bytes) == 5) {
                 String header = new String(bytes);
                 isPdf = Objects.equals(header, "%PDF-");
             }