单机搭建安卓开发环境，前三篇主要是磨刀霍霍，这一篇将重点介绍JDK、REPO、GIT及编译工具的安装，下载项目代码并编译。特别说明，以下操作基于64位12.04 Server版Ubuntu。若采用其他版本系统，请参考Google官方操作步骤。访问不了的同学，请找大师(蓝灯)，他能助你一臂之力。
1)安装OpenJDK 7
sudo apt-get install openjdk-7-jdk --force-yes –y
安装OpenJDK8
sudo add-apt-repository ppa:openjdk-r/ppa
sudo apt-get update
sudo apt-get install openjdk-8-jdk --force-yes -y
查看java的版本
java –version
java version "1.7.0_95"
OpenJDK Runtime Environment (IcedTea 2.6.4) (7u95-2.6.4-0ubuntu0.12.04.1)
OpenJDK 64-Bit Server VM (build 24.95-b01, mixed mode)
设置环境变量
vim ~/.profile
在末尾添加如下配置，保存并退出
export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
export CLASSPATH=.:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$CLASSPATH
export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH
终端输入如下命令使配置生效
source ~/.profile
2)安装google推荐的编译工具
sudo apt-get install gnupg flex bison gperf build-essential --force-yes -y
sudo apt-get install zip curl libc6-dev libncurses5-dev:i386 x11proto-core-dev --force-yes -y
sudo apt-get install libx11-dev:i386 libreadline6-dev:i386 --force-yes -y
sudo apt-get install libgl1-mesa-dev g++-multilib mingw32 tofrodos --force-yes -y
sudo apt-get install python-markdown libxml2-utils xsltproc zlib1g-dev:i386 --force-yes -y
sudo apt-get install libgl1-mesa-dri:i386 dpkg-dev --force-yes –y
3)安装repo
下载repo V1.22国内定制版，已处理原版在国内使用时出现如下错误提示：
fatal: Cannot get https://gerrit.googlesource.com/git-repo/clone.bundle
fatal: error [Errno 101] Network is unreachable
将repo拷贝到/bin目录下，并修改其属性
sudo cp /home/repo /bin/
sudo chmod a+x /bin/repo
4)安装git
sudo apt-get install git --force-yes –y
配置用户邮箱及用户名
git config --global user.email "hjb@mail.com"
git config --global user.name "hjb"
配置完成后可通过git config --list查看配置信息，或通过cat ~/.gitconfig查看git配置文件的详细信息。
5)创建密钥，并添加到服务器端
ssh-keygen -t rsa -C hjb@bonovo.com
拷贝id_rsa.pub并重命名，然后复制到服务器
cp /home/hjb/.ssh/id_rsa.pub /home/hjb/id_rsa.pub.hjb113
在git服务器端登录bnv用户,并执行如下命令，
cat /home/hjbang/id_rsa.pub.hjb113 >> /home/bnv/.ssh/authorized_keys
6)本地创建project目录mt8735，准备下载代码
cd ~
mkdir mt8735
cd mt8735
7)同步代码
repo init -u bnv@192.168.1.12:/home/git/MTK/lp5.1-mt8735m-mirror/bonovo/platform/manifests.git -b default
repo sync
repo forall -c git checkout lp5.1-mt6735m
repo forall -c git checkout mt8735-avn401
repo forall -c git pull
8)安装ccache，并配置ccache
sudo apt-get install -y ccache
配置.bashrc
sudo vim ~/.bashrc
末尾添加
export USE_CCACHE=1
使配置及时生效
source ~/.bashrc
查看设置状态:
echo $USE_CCACHE
9)编译project
cd ~/mt8735
prebuilts/misc/linux-x86/ccache/ccache -M 50G
. build/envsetup.sh
launch 25
make update-api
make update-api，大概需要花18分钟，详细信息如下，
Docs droiddoc: out/target/common/docs/doc-comment-check DroidDoc took 513 sec. to write docs to out/target/common/docs/doc-comment-check Copying current.txt Copying removed.txt Docs droiddoc: out/target/common/docs/system-api-stubs DroidDoc took 13 sec. to write docs to out/target/common/docs/system-api-stubs Copying system-current.txt Copying system-removed.txt #### make completed successfully (17:54 (mm:ss)) ####
View Code
编译Android5.1系统
make –j24
编译过程非常漫长，可以通过如下命令查看cahe使用情况，
watch -n1 -d prebuilts/misc/linux-x86/ccache/ccache -s
cache directory /home/hjb/.ccache cache hit (direct) 0 cache hit (preprocessed) 0 cache miss 43927 called for link 1209 preprocessor error 732 unsupported source language 968 unsupported compiler option 2 files in cache 138583 cache size 18.0 Gbytes max cache size 50.0 Gbytes
可以看到cache大概有18GB，故使用ccache,第一次编译的时间会比不用cache更长,但之后编译速度将会有很大提升。
经过4个半小时，第一次编译终于成功了，详细信息如下，
Creating filesystem with parameters: Size: 1610612736 Block size: 4096 Blocks per group: 32768 Inodes per group: 8192 Inode size: 256 Journal blocks: 6144 Label: Blocks: 393216 Block groups: 12 Reserved block group size: 95 Created filesystem with 2436/98304 inodes and 221139/393216 blocks Install system fs image: out/target/product/mt8735_tb_l1/system.img out/target/product/mt8735_tb_l1/system.img+out/target/product/mt8735_tb_l1/obj/PACKAGING/recovery_patch_intermediates/recovery-from-boot.p maxsize=1644331392 blocksize=4224 total=881392372 reserve=16612992 #### make completed successfully (04:25:03 (hh:mm:ss)) ####
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修改内核模块代码，重新编译系统镜像大概需要13分钟，详细信息如下，
Creating filesystem with parameters: Size: 1610612736 Block size: 4096 Blocks per group: 32768 Inodes per group: 8192 Inode size: 256 Journal blocks: 6144 Label: Blocks: 393216 Block groups: 12 Reserved block group size: 95 Created filesystem with 2436/98304 inodes and 221139/393216 blocks Install system fs image: out/target/product/mt8735_tb_l1/system.img out/target/product/mt8735_tb_l1/system.img+out/target/product/mt8735_tb_l1/obj/PACKAGING/recovery_patch_intermediates/recovery-from-boot.p maxsize=1644331392 blocksize=4224 total=881392372 reserve=16612992 #### make completed successfully (13:04 (mm:ss)) ####
View Code
虽然在SSD上编译，这个时间会缩短到5分钟左右，但还是比较长。所以在调试内核驱动模块时，最好使用动态加载模块的方式，以提高工作效率。
至此，Android系统编译的环境基本搭建完成，后一篇将介绍如何搭建Android应用开发的环境。