Name: bkR10012 Date: 05/08/2001


According to the spec. of the class javax.imageio.ImageWriter
the default implementation throws an UnsupportedOperationException
for almost all unsupported operation.

But for methods replacePixels and endReplacePixels spec says:
"
.....
     The default implementation throws an IllegalStateException."

I suppose that behavior of all methods should be similar
and these methods should throw UnsupportedOperationException.

Also spec. says about endWriteEmpty and endInsertEmpty methods:
"
.....
     The default implementation throws an UnsupportedOperationException
     if the output is non-null. "

But these methods throw unexpected IllegalStateException.

Note also that UnsupportedOperationException is not listed in
the Throws section of the methods spec.

See test source and log below.
---------------------------------------- test.java
import javax.imageio.*;
import javax.imageio.spi.*;
import javax.imageio.metadata.*;
import javax.imageio.stream.MemoryCacheImageOutputStream;
import java.io.IOException;
import java.io.ByteArrayOutputStream;

public class test {
    private final static byte[] ba = {};

    public static void main(String argv[]) {

        ImageWriter iwriter = new DummyImageWriterImpl(null);
        MemoryCacheImageOutputStream mcios = new MemoryCacheImageOutputStream
            (new ByteArrayOutputStream());
        iwriter.setOutput(mcios);

        try {
            iwriter.endWriteEmpty();
        } catch (UnsupportedOperationException e) {
            System.out.println("endWriteEmpty: OKAY");
        } catch (Throwable ee) {
            System.out.println("endWriteEmpty Unexpected exception: " + ee);
        }

        try {
            iwriter.endInsertEmpty();
        } catch (UnsupportedOperationException e) {
            System.out.println("endInsertEmpty: OKAY");
        } catch (Throwable ee) {
            System.out.println("endInsertEmpty Unexpected exception: " + ee);
        }
    }
}

class DummyImageWriterImpl extends ImageWriter {

    public DummyImageWriterImpl(ImageWriterSpi originatingProvider) {
        super(originatingProvider);
    }
    public IIOMetadata convertImageMetadata(IIOMetadata inData,
                                            ImageTypeSpecifier imageType,
                                            ImageWriteParam param) {
        return null;
    }
    public IIOMetadata convertStreamMetadata(IIOMetadata inData,
                                             ImageWriteParam param) {
        return null;
    }
    public IIOMetadata getDefaultImageMetadata(ImageTypeSpecifier imageType,
                                               ImageWriteParam param) {
        return null;
    }
    public IIOMetadata getDefaultStreamMetadata(ImageWriteParam param) {
        return null;
    }
    public void write(IIOMetadata streamMetadata,
                      IIOImage image,
                      ImageWriteParam param) throws IOException {
        return;
    }
}
----------------------------------------
% java -version
java version "1.4.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b63)
Java HotSpot(TM) Client VM (build 1.4.0-beta-b63, mixed mode)
% java test
endWriteEmpty Unexpected exception: java.lang.IllegalStateException: No call to
prepareInsertEmpty!
endInsertEmpty Unexpected exception: java.lang.IllegalStateException: No call to
prepareInsertEmpty!
----------------------------------------
This bug causes failures of the new JCK tests
api/javax_imageio/ImageWriter/index.html#endWriteEmpty
api/javax_imageio/ImageWriter/index.html#endInsertEmpty

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