java.lang.IllegalArgumentException: adding container's parent to itself

1、错误描述

Exception in thread "main" java.lang.IllegalArgumentException: adding container's parent to itself
	at java.awt.Container.checkAddToSelf(Container.java:472)
	at java.awt.Container.addImpl(Container.java:1083)
	at java.awt.Container.add(Container.java:998)
	at javax.swing.JFrame.addImpl(JFrame.java:562)
	at java.awt.Container.add(Container.java:410)
	at com.you.model.JListFrame.<init>(JListFrame.java:56)
	at com.you.model.JListFrame.main(JListFrame.java:71)Exception in thread "main" java.lan