安装android studio for Ubuntu12.04.4-------(1)

1安装jdk8

joe@joe-Aspire-Z3730:~$ sudo add-apt-repository ppa:webupd8team/java
You are about to add the following PPA to your system:
 Oracle Java (JDK) Installer (automatically downloads and installs Oracle JDK7 / JDK8 / JDK9). There are no actual Java files in this PPA.

Important -> Why Oracle Java 7 And 6 Installers No Longer Work: http://www.webupd8.org/2017/06/why-oracle-java-7-and-6-installers-no.html

Ubuntu 16.10 Yakkety Yak is no longer supported by Canonical (and thus, Launchpad and this PPA). The PPA supports Ubuntu 17.10, 17.04, 16.04, 14.04 and 12.04.

More info (and Ubuntu installation instructions):
- for Oracle Java 7: http://www.webupd8.org/2012/01/install-oracle-java-jdk-7-in-ubuntu-via.html
- for Oracle Java 8: http://www.webupd8.org/2012/09/install-oracle-java-8-in-ubuntu-via-ppa.html

Debian installation instructions:
- Oracle Java 7: http://www.webupd8.org/2012/06/how-to-install-oracle-java-7-in-debian.html
- Oracle Java 8: http://www.webupd8.org/2014/03/how-to-install-oracle-java-8-in-debian.html

Oracle Java 9 (for both Ubuntu and Debian): http://www.webupd8.org/2015/02/install-oracle-java-9-in-ubuntu-linux.html

Oracle JDK 9 is now considered stable. There are currently only 64bit builds (no other builds are available for download: http://www.oracle.com/technetwork/java/javase/downloads/index.html )
 More info: https://launchpad.net/~webupd8team/+archive/ubuntu/java
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmp88YJjN/secring.gpg' created
gpg: keyring `/tmp/tmp88YJjN/pubring.gpg' created
gpg: requesting key EEA14886 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmp88YJjN/trustdb.gpg: trustdb created
gpg: key EEA14886: public key "Launchpad VLC" imported
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK

2: joe@joe-Aspire-Z3730:~$ sudo apt-get update

3:sudo apt-get install oracle-java8-installer 出现错误，没办法，只好参考 "Ubuntu 安装 JDK8 的两种方式(http://www.php.cn/java-article-368993.html)"中所说方法进行安装。后来太晚没有这样安装，次日早上仍是按步骤3直接安装成功了。

4:

joe@joe-Aspire-Z3730:~$ java -version
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)
这说明原来的open jdk被替换了。若是要编译android源代码则能够经过下面的步骤5将jdk换回原来的版本。

5：

joe@joe-Aspire-Z3730:~$ update-java-alternatives -l
java-1.6.0-openjdk-amd64 1061 /usr/lib/jvm/java-1.6.0-openjdk-amd64
java-1.7.0-openjdk-amd64 1051 /usr/lib/jvm/java-1.7.0-openjdk-amd64
java-8-oracle 1081 /usr/lib/jvm/java-8-oracle

joe@joe-Aspire-Z3730:~$ echo $JAVA_HOME
/usr/lib/jvm/java-7-openjdk-amd64/

joe@joe-Aspire-Z3730:~$ update-java-alternatives -s java-1.7.0-openjdk-amd64
update-java-alternatives: no root privileges
joe@joe-Aspire-Z3730:~$ sudo update-java-alternatives -s java-1.7.0-openjdk-amd64
joe@joe-Aspire-Z3730:~$ java -version
java version "1.7.0_121"
OpenJDK Runtime Environment (IcedTea 2.6.8) (7u121-2.6.8-1ubuntu0.12.04.3)
OpenJDK 64-Bit Server VM (build 24.121-b00, mixed mode)

joe@joe-Aspire-Z3730:~$ sudo update-java-alternatives -s java-8-oracle
joe@joe-Aspire-Z3730:~$ java -version
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)

6:下面的命令执行以后，感受是否是也将JAVA_HOME环境变量改一改???(没试过，感受最好也对应改一改)

joe@joe-Aspire-Z3730:~$ echo $JAVA_HOME
/usr/lib/jvm/java-7-openjdk-amd64/

joe@joe-Aspire-Z3730:~$ ls /usr/lib/jvm
default-java              java-1.7.0-openjdk-amd64  java-6-openjdk-common
java-1.6.0-openjdk        java-6-openjdk            java-7-openjdk-amd64
java-1.6.0-openjdk-amd64  java-6-openjdk-amd64      java-8-oracle

7:

joe@joe-Aspire-Z3730:~$ gedit .profile

JAVA_HOME=/usr/lib/jvm/java-8-oracle/  
PATH=$PATH:$HOME/bin:$JAVA_HOME/bin 
CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tool.jar 
export JAVA_HOME  
export PATH
export CLASSPATH

8:关闭终端再重启一个终端

joe@joe-Aspire-Z3730:~$ echo $JAVA_HOME
/usr/lib/jvm/java-7-openjdk-amd64/