re-bootstrap Ubuntu 15.04 with JAVA 8 + NetBeans

• Remove all the Java related packages (Sun, Oracle, OpenJDK, IcedTea plugins, GIJ):
  $ dpkg-query -W -f='${binary:Package}\n' | grep -E -e '^(ia32-)?(sun|oracle)-java' -e '^openjdk-' -e '^icedtea' -e '^(default|gcj)-j(re|dk)' -e '^gcj-(.*)-j(re|dk)' -e '^java-common' | xargs sudo apt-get -y remove
$ sudo apt-get -y autoremove
• Purge config files:

  $ dpkg -l | grep ^rc | awk '{print($2)}' | xargs sudo apt-get -y purge

• Remove Java config and cache directory:

  $ sudo bash -c 'ls -d /home/*/.java' | xargs sudo rm -rf

• Remove manually installed JVMs:

  $ sudo rm -rf /usr/lib/jvm/*

• Remove Java entries, if there is still any, from the alternatives:

  $ for g in ControlPanel java java_vm javaws jcontrol jexec keytool mozilla-javaplugin.so orbd pack200 policytool rmid rmiregistry servertool tnameserv unpack200 appletviewer apt extcheck HtmlConverter idlj jar jarsigner javac javadoc javah javap jconsole jdb jhat jinfo jmap jps jrunscript jsadebugd jstack jstat jstatd native2ascii rmic schemagen serialver wsgen wsimport xjc xulrunner-1.9-javaplugin.so; do sudo update-alternatives --remove-all $g; done

• Search for possible remaining Java directories:

  $ sudo updatedb
$ sudo locate -b '\pack200'

If the command above produces any output like /path/to/jre1.6.0_34/bin/pack200 remove the directory that is parent of bin, like this:
$ sudo rm -rf /path/to/jre1.6.0_34

Now install the new version of JAVA:

• Update Apt:
  $ sudo add-apt-repository ppa:webupd8team/java
$ sudo apt-get update
• Install JAVA 8:
  $ sudo apt-get install oracle-java8-installer
• Update JAVA 8 environment variables:
  $ sudo apt-get install oracle-java8-set-default

Now install netbeans which is a straight forward google search and download (ex: netbeans-file.sh). Then $ chmod +x netbeans-file.sh and run it $ ./ netbeans-file.sh