デバッグ中に、sun.jkernel.DownloadManager が表示されることがあります。なぜそれが起こるのですか?
http://www.docjar.com/html/api/sun/jkernel/DownloadManager.java.html
/**
* Handles the downloading of additional JRE components. The bootstrap class
* loader automatically invokes DownloadManager when it comes across a resource
* that can't be located.
*
*@author Ethan Nicholas
*/
public class DownloadManager extends BootClassLoaderHook {