The basic sequence of build commands is as follows:
Initialize the environment with the envsetup.sh script. Note that replacing "source" with a single dot saves a few characters, and the short form is more commonly used in documentation.
$ source build/envsetup.sh
or
$ . build/envsetup.sh
Choose which target to build with lunch. The exact configuration can be passed as an argument, e.g.
$ lunch full-eng
The example above refers to a complete build for the emulator, with all debugging enabled.
If run with no arguments lunch will prompt you to choose a target from the menu.
All build targets take the form DEVICE-BUILDTYPE, where the DEVICE is a codename referring to the particular hardware:
| Codename | Device |
|---|---|
| passion | Nexus One |
| crespo | Nexus S |
| generic | emulator |
and the BUILDTYPE is one of the following:
| Buildtype | Use |
|---|---|
| user | limited access; suited for production |
| userdebug | like "user" but with su access; preferred for debugging |
| eng | unrestricted access |
Build everything with make. GNU make can handle parallel tasks with a -jN argument, and it's common to use a number of tasks N that's between 1 and 2 times the number of hardware threads on the computer being used for the build. E.g. on a dual-E5520 machine (2 CPUs, 4 cores per CPU, 2 threads per core), the fastest builds are made with commands between make -j16 and make -j32.
$ make -j4
You can either run your build on an emulator or flash it on a device. Please note that you have already selected your build target with lunch, and it is unlikely at best to run on a different target than it was built for.
To flash a device, you will need to use fastboot, which should be included in your path after a successful build. Place the device in fastboot mode either manually by holding the appropriate key combination at boot, or from the shell with
$ adb reboot bootloader
Once the device is in fastboot mode, run
$ fastboot flashall -w
The -w option wipes the /data partition on the device; this is useful for your first time flashing a particular device, but is otherwise unnecessary.
The emulator is added to your path automatically by the build process. To run the emulator, type
$ emulator
If you are attempting to build froyo or earlier with Java 1.6, or gingerbread or later with Java 1.5, make will abort with a message such as
************************************************************
You are attempting to build with the incorrect version
of java.
Your version is: WRONG_VERSION.
The correct version is: RIGHT_VERSION.
Please follow the machine setup instructions at
http://source.android.com/download
************************************************************
This may be caused by
failing to install the correct JDK as specified on the Initializing page. Building Android requires Sun JDK 5 or 6 depending on which release you are building.
another JDK that you previously installed appearing in your path. You can remove the offending JDK from your path with:
$ export PATH=${PATH/\/path\/to\/jdk\/dir:/}
Repo is built on particular functionality from Python 2.x and is unfortunately incompatible with Python 3. In order to use repo, please install Python 2.x:
$ apt-get install python
There is a bug in make version 3.82 on Mac OS that prevents building Android.
TODO: what the error looks like with GNU make 3.82 on older builds that don't explicitly detect it.
Follow the instructions on the Initializing page for reverting GNU make from 3.82 to 3.81.
If you are building on an HFS filesystem on Mac OS X, you may encounter an error such as
************************************************************ You are building on a case-insensitive filesystem. Please move your source tree to a case-sensitive filesystem. ************************************************************
Please follow the instructions on the Initializing page for creating a case-sensitive disk image.
On most Linux systems, unprivileged users cannot access USB ports by default. If you see a permission denied error, follow the instructions on the Initializing page for configuring USB access.
If adb was already running and cannot connect to the device after getting those rules set up, it can be killed with adb kill-server. That will cause adb to restart with the new configuration.