Name: dkR10031 Date: 05/23/2001


Specification of the method
javax.imageio.metadata.IIOMetadataNode.getAttribute says:

"Returns:
         The Attr value as a string, or the empty string if that
         attribute does not have a specified or default value."

and does not say anything about exceptions thrown.

However, the implementation (JDK 1.4.0beta, build b65) of the method
throws unspecified NullPointerException when the name of non-existent
attribute is passed to the method.
Also, it's not quite clear from the description what is a precise
meaning of the words: "attribute does not have a specified or default
value". I presumed this means an attribute is not set by the
method setAttribute at least once. Is it correct? In any case, I think
this phrase needs some clarification in the spec.

This bug causes a failure of the new JCK test:
api/javax_imageio/metadata/IIOMetadataNode/index.html#getAttribute

To reproduce the bug run the following test:

------------ test09.java ------------------------
import javax.imageio.metadata.IIOMetadataNode;

public class test09 {

    public static void main(String argv[]) {

        String actValue;

        IIOMetadataNode parent = new IIOMetadataNode("parent");
    
        actValue = parent.getAttribute("attr");
        if (! actValue.equals("")) {
            System.out.println("invalid value for not set attribute: " + actValue);
        } else {
            System.out.println("Passed");
        }
    }
}
------------ Logs -----------------------------
$ 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)

$ javac test09.java

$ java test09
Exception in thread "main" java.lang.NullPointerException
        at
javax.imageio.metadata.IIOMetadataNode.getAttribute(IIOMetadataNode.java:659)
        at test09.main(test09.java:11)

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