安装JDK出现gzip: stdin: not in gzip format的原因

在Ubuntu 中安装JDK7解压缩失败的原因：

The reason the file isn't extracting properly is because the download page is setting a cookie when you accept the license agreement. If you don't have the session cookie when attempting to download the file, it redirects you to an HTML page that tells you to accept the agreement first. If you open the .tar.gz that you're getting from wget, you'll see that it's an HTML file since it's not getting said cookie.

The easiest way to solve it is to download the file first, using your web browser, and then upload it to your web server.

被坑了很久啊。