Install JDK and Tomcat in Linux

Install JDK and Tomcat in Linux


View environment variables
Whereis java
Which java (java execution path)
Echo $ JAVA_HOME
Echo $ PATH

Ii. Installation
Select the location where you want to install java, such as in the/usr/directory, and create a folder named java (mkdir java)

# Mkdir-p/usr/java
Download jdk-8u31-linux-x64.tar.gz to/usr/java.

# Cd/usr/java
# Tar-zxvf jdk-8u31-linux-x64.tar.gz

3. Set Variables
# Vim/etc/profile
Add the following content at the end:
# JAVA
JAVA_HOME =/usr/java/jdk1.8.0 _ 31
CLASSPATH =.: $ JAVA_HOME/lib. tools. jar
PATH = $ JAVA_HOME/bin: $ PATH
Export JAVA_HOME CLASSPATH PATH

Make variables take effect
# Source/etc/profile

Verify whether it is successful
# Java-version
Java version "1.8.0 _ 31"
Java (TM) SE Runtime Environment (build 1.8.0 _ 31-b13)
Java HotSpot (TM) 64-Bit Server VM (build 25.31-b07, mixed mode)

View Variables
# Which java // java execution path
/Usr/java/jdk1.8.0 _ 31/bin/java
# Echo $ JAVA_HOME
/Usr/java/jdk1.8.0 _ 31
# Echo $ PATH
/Usr/java/jdk1.8.0 _ 31/bin:/usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin: /usr/sbin:/usr/bin:/root/bin


4. Uninstall jdk
· Find the _ uninst subdirectory of the jdk installation directory.
· Run the command./uninstall. sh on the shell terminal to uninstall jdk.

5. install tomcat
Download tomcat
Wget http://mirrors.cnnic.cn/apache/tomcat/tomcat-8/v8.0.20/bin/apache-tomcat-8.0.20.tar.gz

(1)decompress apache-tomcat-8.0.20.tar.gz
# Tar-zxvf apache-tomcat-8.0.20.tar.gz
(2) copy the decompressed directory apache-tomcat-8.0.20 to/usr/local and rename it tomcat8.
# Cp-Rapache-tomcat-8.0.20/usr/local/tomcat8
Note:/usr/local/tomcat8 is the directory path we need to fill in when modifying the environment variables.
(3)
Add tomcat Environment Variables
# Vim/etc/profile
Add code
# Set environment variable
JAVA_HOME =/usr/java/jdk1.8.0 _ 31
CLASSPATH =.: $ JAVA_HOME/lib. tools. jar
PATH = $ JAVA_HOME/bin: $ PATH
Export JAVA_HOME CLASSPATH PATH
ExportTOMCAT_HOME =/usr/local/tomcat8
ExportCATALINA_HOME =/usr/local/tomcat8
Modify the application environment variable to make the configuration take effect
# Source/etc/profile

(4) enter the bin directory and start tomcat
# Cd/usr/local/tomcat8/
# Cd bin/
#./Startup. sh

(5) modify the environment variable and restart tomcat.
[Root @ oracledb bin] #./startup. sh
Using CATALINA_BASE:/usr/local/tomcat8
Using CATALINA_HOME:/usr/local/tomcat8
Using CATALINA_TMPDIR:/usr/local/tomcat8/temp
Using JRE_HOME:/usr/java/jdk1.8.0 _ 31
Using CLASSPATH:/usr/local/tomcat8/bin/bootstrap. jar:/usr/local/tomcat8/bin/tomcat-juli.jar
Tomcat started.

(6) Disable tomcat
[Root @ oracledb bin] #./shutdown. sh
Using CATALINA_BASE:/usr/local/tomcat8
Using CATALINA_HOME:/usr/local/tomcat8
Using CATALINA_TMPDIR:/usr/local/tomcat8/temp
Using JRE_HOME:/usr/java/jdk1.8.0 _ 31
Using CLASSPATH:/usr/local/tomcat8/bin/bootstrap. jar:/usr/local/tomcat8/bin/tomcat-juli.jar

(7) view Processes
[Root @ oracledb bin] # ps-ef | grep tomcat
Root 22552 1 99 09:58 pts/0 00:00:05/usr/java/jdk1.8.0 _ 31/bin/java-Djava. util. logging. config. file =/usr/local/tomcat8/conf/logging. properties-Djava. util. logging. manager = org. apache. juli. classLoaderLogManager-Djava. endorsed. dirs =/usr/local/tomcat8/endorsed-classpath/usr/local/tomcat8/bin/bootstrap. jar:/usr/local/tomcat8/bin/tomcat-juli.jar-Dcatalina. base =/usr/local/tomcat8-Dcatalina. home =/usr/local/tomcat8-Djava. io. tmpdir =/usr/local/tomcat8/temp org. apache. catalina. startup. bootstrap start
Root 22581 22284 0 00:00:00 pts/0 grep tomcat

(8) add management Permissions
By default, Tomcat does not provide an account with administrative permissions, so you need to add an account with such permissions. Role manager-gui has this permission, but the two roles and their corresponding users are not set in the System user control file tomcat-users.xml, so you need to add such roles and users, to open the tomcat-users.xml file, add the following:
<Rolerolename = "manager-gui"/>
<Userusername = "manager" password = "manager" roles = "manager-gui"/>
Restart the Tomcat server, and the file modification takes effect.