1. JDK installation steps in Linux environment
1.1 Upload jdk-7u75-linux-x64.tar.gz and extract it
1. Upload the downloaded jdk-7u75-linux-x64.tar.gz file to the Linux server , or download it online by wget .
Download address: http://www.oracle.com/technetwork/cn/java/javase/downloads/jdk7-downloads-1880260.html (The version of jdk1.7 is provided here)
2. Press jdk- 7u75 -linux-x64.tar.gz .
The decompression command is : tar –zxvf jdk-7u75-linux-x64.tar.gz
The decompressed file directory structure is:
1.2 Set PATH
1. Create the java directory in the /usr/local/ directory . The command is mkdir /usr/local/java
2. Move the decompressed java/jdk1.7.0_75 directory including all files in the directory to /usr/local/java/
The copy command is : mv ../jdk1.7.0_75 /usr/local/java/
3. Modify the profile to set the PATH
Execute the command : vi /etc/profile
Append the following to the end of the file:
export JAVA_HOME=/usr/local/java/jdk1.7.0_75 export JRE_HOME=/usr/local/java/jdk1.7.0_75/jre export PATH=$PATH:/usr/local/java/jdk1.7.0_75/bin export CLASSPATH=./:/usr/local/java/jdk1.7.0_75/lib:/usr/local/java/jdk1.7.0_75/jre/lib
Enter : wq to exit and save, then restart the Linux system.
1.3 Verify the installation result
After restarting the system, enter: java -version , if you see the screenshot below, your jdk has been installed successfully.
2. Possible problems
2.1 Before installation, first uninstall the JDK installed by Centos
[root@localhost soft]# java -version java version “1.4.2″ thou (GNU libgcj) version 4.1.2 20071124 (Red Hat 4.1.2-42) Note that according to my installation under 5.2, it seems that the installation of jdk6 cannot take effect without uninstalling the 1.4 that comes with it. In order to avoid this situation, we first uninstall the 1.4 version of the jdk that comes with it. [root@localhost soft]# rpm -qa | grep jdk [root@localhost soft]# rpm -qa | grep gcj libgcj-4.1.2-42.el5 java-1.4.2-gcj-compat-1.4.2.0-40jpp.115 First confirm the specific version number of jdk above, and then [root@localhost jdk1.6.0_11]# yum -y remove java-1.4.2-gcj-compat-1.4.2.0-40jpp.115 Setting up Remove Process Resolving Dependencies…………..(Start uninstalling) Removed: java-1.4.2-gcj-compat.i386 0:1.4.2.0-40jpp.115 Dependency Removed: antlr.i386 0:2.7.6-4jpp.2 bsf.i386 0:2.3.0-11jpp.1 bsh.i386 0:1.3.0-9jpp.1 gjdoc.i386 0:0.7.7-12.el5 hsqldb.i386 1:1.8.0.9-1jpp.2 openoffice.org-calc.i386 1:2.3.0-6.5.el5 openoffice.org-core.i386 1:2.3.0-6.5.el5 openoffice.org-draw.i386 1:2.3.0-6.5.el5 openoffice.org-graphicfilter.i386 1:2.3.0-6.5.el5 openoffice.org-impress.i386 1:2.3.0-6.5.el5 openoffice.org-langpack-zh_CN.i386 1:2.3.0-6.5.el5 openoffice.org-langpack-zh_TW.i386 1:2.3.0-6.5.el5 openoffice.org-math.i386 1:2.3.0-6.5.el5 openoffice.org- writer.i386 1:2.3.0-6.5.el5 openoffice.org-xsltfilter.i386 1:2.3.0-6.5.el5 tomcat5-jsp-2.0-api.i386 0:5.5.23-0jpp.7.el5 tomcat5-servlet-2.4-api.i386 0:5.5.23-0jpp.7.el5 xalan- j2.i386 0:2.7.0-6jpp.1 xerces-j2.i386 0:2.7.1-7jpp.2 xml-commons-apis.i386 0:1.3.02-0.b2.7jpp.10 xml-commons-resolver.i386 0:1.1-1jpp.12 Complete! (Uninstallation completed)