Java.net missing classes?

Question

I downloaded Oracle's java7 sdk from repository: ppa:webupd8team/java and I run ubuntu 12.04.

When i use sockets etc and other classes from java.net its fine.

But when i search for:

import java.net.SocketOption;
import java.net.StandardSocketOptions;
import java.nio.channels.NetworkChannel;

I cannot find a thing. It says it cannot find the symbol. Do i have to install something more? Is it something that i have to do to work with these classes?

Answer 1

我在src.zip中直接在JDK的根文件夹中找到了类的源代码。

Answer 2

I figure it out. I installed OpenJDK from the ubuntu's repository.

Then i switched the default to be OpenJDK:

sudo update-alternatives --config java