The following external link to "The Swing Connection", from the javax.swing package API docs, is a broken link that returns a 404:

http://www.oracle.com/technetwork/java/javase/tech/articles-jsp-139072.html

It is linked from this page:

https://docs.oracle.com/en/java/javase/17/docs/api/java.desktop/javax/swing/package-summary.html#related

The source is here:

https://github.com/openjdk/jdk/blob/jdk-19%2B5/src/java.desktop/share/classes/javax/swing/package-info.java#L135

This link hasn't changed since at least JDK 11.