The ImageIcon(Image) [1] constructor sets the description field to the value of "comment" property if it's a string. The ImageIcon(Image, String) [2] constructor calls ImageIcon(Image). Since the two-parameter constructor explicitly provides the value for the description field, the implicitly set value for description is immediately overwritten, which is wasted work.

This issue was found in the code review [3] for JDK-8159055:

“This is wasted work if the app calls ImageIcon(Image, String) because that promptly over-writes whatever was obtained via this code.”

There's a suggested fix for it [4]:

    public ImageIcon (Image image) {
        String description = null;
        if (image != null) {
            Object o = image.getProperty("comment", null);
            if (o instanceof String) {
                description = (String) o;
            }
        }
        this(image, description);

And the ImageIcon(Image, String) constructor will do the actual work of setting the fields and loading the image.

[1] https://github.com/openjdk/jdk/blob/853319439e7887ddd54f8c4a3d79aa62ec51fd64/src/java.desktop/share/classes/javax/swing/ImageIcon.java#L226-L229
[2] https://github.com/openjdk/jdk/blob/853319439e7887ddd54f8c4a3d79aa62ec51fd64/src/java.desktop/share/classes/javax/swing/ImageIcon.java#L211-L212
[3] https://github.com/openjdk/jdk/pull/25767#discussion_r2155610976
[4] https://github.com/openjdk/jdk/pull/25767#discussion_r2159249820