Eclipse Trouble Shooting : Can't view ojdbc6.jar in package explorer

I copied ojdbc6.jar to jre /lib/ext

but I can't view ojdbc6.jar in package explorer.

I can't see ojdbc6.jar, but I was run and compiled well.

but process as follows, in order to make sure.

windows-> preferences->left.tree.Java.Insstalled JREs ->right.select(your jre to change) -> right.click.button.Edit

JRE system libraries -> button Add External JARs -> select your ojdbc.jar

You can maybe view ojdbc6.jar.