ImageIO.getImageTranscoders: incorrect diagnostic message

Name: ipR10067 Date: 05/21/2001


There seems to be a typo in diagnostic message in method ImageIO.getImageTranscoders.

The message of IllegalArgumentException reads "reader == null!"
even though the parameter "writer" is null and "reader" is not null.

To reproduce the problem run the following test:

---------------------------- source --------------------------------
import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
import javax.imageio.ImageReader;
import java.io.PrintWriter;
import java.io.IOException;
import java.util.Iterator;

public class Test {
    public static void main(String argv[]) {

        String[] Formatnames = null;
        Iterator readers = null;
        ImageReader reader = null;

        /* get reader */
        Formatnames = ImageIO.getReaderFormatNames();
        readers = ImageIO.getImageReadersByFormatName(Formatnames[0]);
        while (readers.hasNext()){
            reader = (ImageReader)readers.next();
            if (reader != null) {
                break;
            }
        }

        try {
               Iterator transcoders = ImageIO.getImageTranscoders(reader, null);
        } catch (IllegalArgumentException iae) {
             System.out.println("writer == null, exception: " + iae.toString());
             return;
        }
        System.out.println("No expected exception was thrown");
        return;
    }
}

---------------------------- log --------------------------------
>java -version
java version "1.4.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b65)
Java HotSpot(TM) Client VM (build 1.4.0-beta-b65, mixed mode)
>java Test
writer == null, exception: java.lang.IllegalArgumentException: reader == null!


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