as you know oracle bans some countries and ... first add key:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update

then use apt-install to install the package:

sudo apt-get install oracle-java7-installer

after getting error 403,use ls:

ls /var/cache/oracle-jdk7-installer/

jar.binfmt  javaws-wrapper.sh  jdk-7u55-linux-x64.tar.gz  wgetrc

copy.tar.gzfilename and search/download it in the web (http://enos.itcollege.ee/~jpoial/download/jdk7/).

then copy downloaded file to cache:

sudo cp ~/Downloads/jdk-7u55-linux-x64.tar.gz /var/cache/oracle-jdk7-installer/

to ensure that you download the correct file,usemd5sum:

md5sum jdk-7u55-linux-x64.tar.gz
9e1fb7936f0e5aaa1e64d36ba640bc1f jdk-7u55-linux-x64.tar.gz

result must match with oracle checksum athttp://www.oracle.com/technetwork/java/javase/downloads/java-se-binaries-checksum-1956892.html

after this if you run the install command,installation will be done correctly using cached file:

sudo apt-get install oracle-java7-installer