Prevent potential NullPointerException

diff --git a/src/main/java/net/pterodactylus/sone/web/UploadImagePage.java b/src/main/java/net/pterodactylus/sone/web/UploadImagePage.java
index 30a5890..a1e987a 100644 (file)
--- a/src/main/java/net/pterodactylus/sone/web/UploadImagePage.java
+++ b/src/main/java/net/pterodactylus/sone/web/UploadImagePage.java
@@ -17,6 +17,7 @@
 
 package net.pterodactylus.sone.web;
 
+import static com.google.common.base.Optional.fromNullable;
 import static java.util.logging.Logger.getLogger;
 
 import java.awt.Image;
@@ -55,8 +56,8 @@ import freenet.support.api.HTTPUploadedFile;
  */
 public class UploadImagePage extends SoneTemplatePage {
 
-       /** The logger. */
        private static final Logger logger = getLogger(UploadImagePage.class.getName());
+       private static final String UNKNOWN_MIME_TYPE = "application/octet-stream";
 
        /**
         * Creates a new “upload image” page.
@@ -154,12 +155,13 @@ public class UploadImagePage extends SoneTemplatePage {
                        ImageInputStream imageInputStream = ImageIO.createImageInputStream(imageDataInputStream);
                        Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(imageInputStream);
                        if (imageReaders.hasNext()) {
-                               return imageReaders.next().getOriginatingProvider().getMIMETypes()[0];
+                               return fromNullable(imageReaders.next().getOriginatingProvider().getMIMETypes())
+                                               .or(new String[] { UNKNOWN_MIME_TYPE })[0];
                        }
                } catch (IOException ioe1) {
                        logger.log(Level.FINE, "Could not detect MIME type for image.", ioe1);
                }
-               return "application/octet-stream";
+               return UNKNOWN_MIME_TYPE;
        }
 
 }