Debian squeeze repository has java 1.6.x and can be easily installed via apt command however, installing sun- java 1.7.x is pain in ass.Here I have complied the steps for installing sun java 1.7.x in Debian squeeze :
Download latest version or whatever is the preference of java1.7.x by following following this post : Sun Java Download
Uncompress it .
JDK 7 package is extracted into ./jdk.1.7.x directory.Check carefully this folder name since Oracle seem to change this occasionally with each update.
Now move the JDK 7 directory to
sudo mkdir -p /usr/lib/jvmsudo mv ./jdk.1.7.x /usr/lib/jvm/jdk1.7.0
Run : sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jdk1.7.0/bin/java" 1 sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.7.0/bin/javac" 1 sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/lib/jvm/jdk1.7.0/bin/javaws" 1
Correct the file ownership and the permissions of the executables:
sudo chmod a+x /usr/bin/java sudo chmod a+x /usr/bin/javac sudo chmod a+x /usr/bin/javaws sudo chown -R root:root /usr/lib/jvm/jdk1.7.0
sudo update-alternatives –config java
Shows java alternatives available debian and would show something like this:
Selection Path Priority Status
* 0 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 auto mode
1 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 manual mode
2 /usr/lib/jvm/java-6-sun/jre/bin/java 63 manual mode
3 /usr/lib/jvm/jdk1.7.0/jre/bin/java 3 manual mode
Press enter to keep the current choice[*], or type selection number: 3
Choose 3 or whichever points to java 1.7.x.
Check the java version via :
java --version command .