I'm trying to install java jre, i usually do it like this

sudo echo 'deb http://www.duinsoft.nl/pkg debs all' >> /etc/apt/sources.list
sudo apt-key adv --keyserver keys.gnupg.net --recv-keys 5CB26B26
sudo apt-get update
sudo apt-get install update-sun-jre
exit

but when i do

sudo echo 'deb http://www.duinsoft.nl/pkg debs all' >> /etc/apt/sources.list

i see

permission denied: /etc/apt/sources.list

When i do

ls -l /etc/apt/sources.list

i see

-rw-r--r-- 1 root root 3360 Aug 26 01:45 /etc/apt/sources.list

When i do

sudo mv /etc/apt/sources.list /etc/apt/sources.list.old
sudo cat /etc/apt/sources.list.old | sudo tee /etc/apt/sources.list

i see

#deb cdrom:[Ubuntu 12.04 LTS _Precise Pangolin_ - Release amd64 (20120425)]/ dists/precise/main/binary-i386/

#deb cdrom:[Ubuntu 12.04 LTS _Precise Pangolin_ - Release amd64 (20120425)]/ dists/precise/restricted/binary-i386/
#deb cdrom:[Ubuntu 12.04 LTS _Precise Pangolin_ - Release amd64 (20120425)]/ precise main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://lb.archive.ubuntu.com/ubuntu/ precise main restricted
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://lb.archive.ubuntu.com/ubuntu/ precise-updates main restricted
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://lb.archive.ubuntu.com/ubuntu/ precise universe
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise universe
deb http://lb.archive.ubuntu.com/ubuntu/ precise-updates universe
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://lb.archive.ubuntu.com/ubuntu/ precise multiverse
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise multiverse
deb http://lb.archive.ubuntu.com/ubuntu/ precise-updates multiverse
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://lb.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://lb.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu precise-security main restricted
deb-src http://security.ubuntu.com/ubuntu precise-security main restricted
deb http://security.ubuntu.com/ubuntu precise-security universe
deb-src http://security.ubuntu.com/ubuntu precise-security universe
deb http://security.ubuntu.com/ubuntu precise-security multiverse
deb-src http://security.ubuntu.com/ubuntu precise-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu precise partner
# deb-src http://archive.canonical.com/ubuntu precise partner

## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
deb http://extras.ubuntu.com/ubuntu precise main
deb-src http://extras.ubuntu.com/ubuntu precise main

and the issue is not solved, i still see that permission error, I'm on a 64 bit laptop

This is a known issue, when you use sudo in this fashion, it won't work right. That is because while the echo command is run as sudo, the >> for append tries to open the file target as a non-sudo user. That is where the permission issue is.

However, please read my two part answer, this gives you a separate solution (sort of):

1:

Use a separate file in /etc/apt/sources.list.d/ which contains the deb instruction you're saying now. YOu'd still need to use sudo, though, to edit / create the file.

2:

A solution would be to do sudo su -c "echo 'deb http://www.duinsoft.nl/pkg debs all' >> /etc/apt/sources.list", which tells the system to run that as superuser, which you get access to by using 'sudo' in front of the 'su' command.

PLEASE NOTE that the su command used outside of the command I stated here is dangerous, so you should only use this method if you absolutely need it.

What happens with the command is that echo is run as root, but not >>. Try the following instead:

echo 'deb http://www.duinsoft.nl/pkg debs all' | sudo tee -a /etc/apt/sources.list

alternatively, you could do it in two steps:

sudo -i

echo 'deb http://www.duinsoft.nl/pkg debs all' >> /etc/apt/sources.list

exit

What this command does is appending deb http://www.duinsoft.nl/pkg debs all to /etc/apt/sources.list. Let's do it in an other method! Just open that file and append it manually!

sudo nano /etc/apt/sources.list

Then add deb http://www.duinsoft.nl/pkg debs all to end of it and press Ctrl + O and then ENTER to save the changes and finally Ctrl + X to quit nano.

You can jump to the next command now...

Just simply add sudo again after >> will work for this one. Try this

sudo echo 'deb http://www.duinsoft.nl/pkg debs all' >> sudo /etc/apt/sources.list

I literally just had same issue and didn't want to backtrack and this worked for me.