1. Download JDK
The latest JDK version is: Java SE Development Kit 7u5
Download address: http://download.oracle.com/otn-pub/java/jdk/7u5-b06/jdk-7u5-linux-i586.tar.gz
Check out the latest: http://www.oracle.com/technetwork/java/javase/downloads/index.html
2. Unzip the installation
We install the JDK to this path: /usr/lib/jvm
If there is no such directory (of course not the first time), we will create a new directory
|
1
2
|
cd
/
usr
/
lib
sudo
mkdir
jvm
|
After the establishment is complete, we go to the directory of the compressed package we just downloaded, unzip it into the folder we just created, and modify the name to facilitate our management.
|
1
2
3
|
sudo
tar
zxvf
.
/
jdk
-
7
-
linux
-
i586
.tar
.gz
-
C
/
usr
/
lib
/
jvm
cd
/
usr
/
lib
/
jvm
sudo
mv
jdk1
.
7.0_05
/
jdk7
|
3. Configure environment variables
| 1 | gedit ~/.bashrc |
add at the end of the opened file
|
1
2
3
4
|
export
JAVA_HOME
=
/
usr
/
lib
/
jvm
/
jdk7
export
JRE_HOME
=
$
{
JAVA_HOME
}
/
jre
export
CLASSPATH
=
.
:
$
{
JAVA_HOME
}
/
lib
:
$
{
JRE_HOME
}
/
lib
export
PATH
=
$
{
JAVA_HOME
}
/
bin
:
$
PATH
|
Save and exit, then enter the following command to make it take effect
| 1 | source ~/.bashrc |
4. Configure the default JDK (in general, this step can be omitted)
Because some Linux distributions already have a default JDK, such as OpenJDK, etc. So in order to make the JDK version we just installed become the default JDK version, we also need to perform the following configuration.
Execute the following command:
|
1
2
|
sudo
update
-
alternatives
--
install
/
usr
/
bin
/
java
java
/
usr
/
lib
/
jvm
/
jdk7
/
bin
/
java
300
sudo
update
-
alternatives
--
install
/
usr
/
bin
/
javac
javac
/
usr
/
lib
/
jvm
/
jdk7
/
bin
/
javac
300
|
Note: If the above two commands cannot find the path, just restart the computer and repeat the above two lines of code and it will be OK.
Execute the following code to see the current various JDK versions and configurations:
| 1 | sudo update-alternatives --config java |
5. Test
Open a terminal and enter the following command:
| 1 | java -version |
Show results:
|
1
2
3
|
java
version
"1.7.0_05"
Java
(
TM
)
SE
Runtime
Environment
(
build
1.7.0_05
-
b05
)
Java
HotSpot
(
TM
)
Server
VM
(
build
23.1
-
b03
,
mixed
mode
)
|
This means that the java command is ready to run.