[JAVA] Eccezione in FileSeekableStream durante serializzazione

[cicciox80]

ciaop raga, dopo aver eseguito questo codice

    try {
      FileSeekableStream stream = new FileSeekableStream(nome);
      RenderedOp img = JAI.create("stream", stream);
      return img;
    }
    catch (IOException e) {
      throw new MEDExceptions(MEDExceptions.IO_IMAGE_ERROR);
    }

metto la variavile img come attributo all'ìnterno di un altro oggetto Paziente, il quale a sua volta implements Serializable, dopodiché invio l'oggetto da un'applicazione server ad una client, con l'istruzione:

   packetOut.writeObject(paziente);

Il problema è che quando viene eseguita tale istruzione, viene generata l'eccezione:

java.lang.RuntimeException: com.sun.media.jai.codec.FileSeekableStreamNon-serializable parameter in this operation`s ParameterBlock.

at javax.media.jai.OperationNodeSupport.writeObject(OperationNodeSupport.java:754)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:809)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1296)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1247)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1052)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1332)
at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:367)
at javax.media.jai.RenderedOp.writeObject(RenderedOp.java:3015)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:809)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1296)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1247)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1052)
at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1224)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1050)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1332)
at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:367)
at java.util.Vector.writeObject(Vector.java:1017)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:809)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1296)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1247)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1052)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1332)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1304)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1247)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1052)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:278)
at ClientServer.GestoreRichiesta.processaRichiesta(GestoreRichiesta.java:60)
at ClientServer.GestoreRichiesta.run(GestoreRichiesta.java:116)

Qual'è il problema?

[LeleFT]

Ma la classe RenderedOp implementa Serializable?


Ciao.

[cicciox80]

sì, implementa serializable. Perdipiù abbiamo un altro attributo dello stesso tipo ma caricato in maniera differente, più precisamente così:

      RandomAccessFile input = new RandomAccessFile(nome, "r");

      int width, height;
      String header = input.readLine();
      width = Integer.parseInt(header.substring(0, header.indexOf(" ")));
      height = Integer.parseInt(header.substring(header.indexOf(" ") + 1,
                                                 header.length()));
      int size = width * height;
      int dsize = 2 * size;

      short[] uArray = new short[size];
      int[] iArray = new int[size];
      byte[] bArray = new byte[dsize];
      BufferedImage bufferedImage =
          new BufferedImage(width, height, BufferedImage.TYPE_USHORT_GRAY);

      WritableRaster raster = bufferedImage.getRaster();
      input.read(bArray);
      int index = 0;
      for (int h = 0; h < height; h++) {
        for (int w = width - 1; w >= 0; w--) {
          raster.setSample(w, h, 0,
                           ( (bArray[index++] & 0xff) << 8)
                           | (bArray[index++] & 0xff));
        }
      }

      RenderedOp image;
      if (!isLeft(nome)) {
        ParameterBlock pb = new ParameterBlock();
        pb.addSource(bufferedImage);
        pb.add(TransposeDescriptor.FLIP_HORIZONTAL);
        image = (RenderedOp) JAI.create("transpose", pb, null);
      }
      else {
        ParameterBlock pb = new ParameterBlock();
        pb.addSource(bufferedImage);
        pb.add(new double[] {0.0});
        image = (RenderedOp) JAI.create("addconst", pb, null);
      }
      return image;

Quando l'oggetto paziente contiene un'istanza solo di questa RenderedOp, l'invio funziona. Ma se invece contiene un'istanza della RenderedOp creata come specificato precedentemente, l'invio fallisce.