Name: ipR10067 Date: 08/22/2001



The specification for the method
javax.imageio.stream.ImageOutputStreamImpl.writeBit reads:

"public void writeBit(int bit) throws IOException
...
If any bits of a particular byte have never been set
at the time the byte is flushed to the destination,
those bits will be set to 0 automatically.
"

But it does not work as expected:
===================== test.java =======================
import java.io.*;
import javax.imageio.stream.FileCacheImageOutputStream;

public class test {
    public static void main (String argv[]) throws Exception {
        OutputStream ostream = new ByteArrayOutputStream();
        File f = null;
        FileCacheImageOutputStream fcios = new FileCacheImageOutputStream(ostream, f);

        fcios.writeBit(1);

        fcios.seek(0);

        int r1 = fcios.read();
        if( r1 != 128 ) {
            System.out.println("Failed: " + r1 + "(should be 128)");
            return;
        }

        System.out.println("Passed");
    }
}

===================== log =======================
%java -version
java version "1.4.0-beta2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta2-b77)
Java HotSpot(TM) Client VM (build 1.4.0-beta2-b77, mixed mode)
% javac -d . test.java
% java test
Failed: 255(should be 128)
 
The same problem exists for the method writeBits.

This bug affects new JCK tests:
api/javax_imageio/stream/FileCacheImageOutputStream/index.html#seek[seek002]
api/javax_imageio/stream/FileCacheImageOutputStream/index.html#write[write0021]
api/javax_imageio/stream/FileCacheImageOutputStream/index.html#write[write002]
api/javax_imageio/stream/FileImageOutputStream/index.html#seek[seek002]
api/javax_imageio/stream/MemoryCacheImageOutputStream/index.html#seek[seek002]
api/javax_imageio/stream/MemoryCacheImageOutputStream/index.html#write[write0021]
api/javax_imageio/stream/MemoryCacheImageOutputStream/index.html#write[write002]

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