Preparing to build Gingerbread / Android on Ubuntu.

This is a quick tip on how to setup Ubuntu to build Android from scrap.

Android / Gingerbread build process itself is pretty straightforward if you follow the standard documentation: http://source.android.com/source/building.html.

What will stop you is that Ubuntu has, in my opinion, two things that annoy every java developer:
a) openjdk / fastjar
b) pulseaudio! Neah, this just annoys everybody :))

This crippled Java kills Gingerbread build process with errors like:

out/target/common/obj/APPS/Camera_intermediates/src/com/android/camera/R.java:10:
cannot access java.lang.Object
bad class file: java/lang/Object.class(java/lang:Object.class)
unable to access file: corrupted zip file
Please remove or make sure it appears in the correct subdirectory of the
classpath.
public final class R {
^

For all the details and the solution here’s how to fix: https://groups.google.com/group/pandaboard/browse_thread/thread/2ad9f0ae099e7db1?fwc=1&pli=1

Correcting the fastjar mess :

sudo update-alternatives --config jar

and selecting the proper Sun / Oracle JDK fastjar alternative.

It now builds correctly in just under one hour! (E8500 / 2Gb DDRAM 800Mhz / RAID-0).

# time make -j8
...
real 59m26.427s
user 69m54.414s
sys 9m24.187s

So, to get rid of OpenJDK/fastjar, issue the following commands:

apt-get remove icedtea-6-jre-cacao icedtea6-plugin openjdk-6-dbg openjdk-6-demo openjdk-6-doc openjdk-6-jre openjdk-6-jre-headless openjdk-6-jre-lib openjdk-6-source openjdk-6-jre-zero cacao-source default-jdk default-jdk-doc default-jre default-jre-headless

as well as:

apt-get remove fastjar

It will actually remove much more (as there are many dependencies not used), but this does not affect the build process of Gingerbread as long as you have Sun’s JDK installed.

Make sure you check the output and you don’t delete something you need.