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  1. JDK
  2. JDK-8101011

Make Image class support exceptions for both asynchronous and synchronous loading

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      In our application we are loading a PNG image, and apparently this leads to an error. However, the error is never reported by the Image class - no exception is ever thrown. While debugging I noticed, Image has an isError method, and it returns true, so clearly something went wrong.

      I understand that for asynchronously loaded images you cannot throw an exception because the load is dispatched to a different thread, but in our case we are loading the image synchronously like this

      Image image = new Image(absoluteUri, width, height, true, true, false);

      as you can see, the background loading parameter is false. Hence, I think it is reasonable to expect that the call to new Image will block while loading and then throw an exception, if the loading fails. But it does not - the class simply sets the image error property to true and returns.

      I request that the Image class is improved to use a number of exceptions representing each of the ways the loading could go wrong - i.e. ImageNotFoundException, UnsupportedImageFormatException, ...

      For synchronous loading I request that this exception is thrown immediately, and for asynchronous loading I request that the exception is stored in the image instance using a new exception property. This will allow me to handle asynchronous errors like this

      if(image.isError()) {
        Exception e = image.getException()

        //log the exception
        //tell the user that something went wrong.
      }

      and allow me to handle synchronous errors like this

      try {
        Image image = new Image(absoluteUri, width, height, true, true, false);
      }
      catch(ImageNotFoundException) {
        //log the exception
        //tell the user that something went wrong.
      }
      ...

            lnerad Ľubomír Nerád (Inactive)
            risaksen Randahl Isaksen
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