centos 安装java和tomcat

一、yum环境

　　1、查看yum是否安装

rpm -qa | grep yum

二、Java环境

　　1、查看java是否安装，若没有，进行安装

rpm -qa | grep java

　　2、查找java-1.8.0的可以使用的安装包

yum list | grep java-1.8.0-openjdk

　　3、安装java-1.8.0-openjdk所有的文件

yum -y install java-1.8.0-openjdk*

　　4、查看版本号

java -version

　　5、输入javac,如果能看到内容输出就说明已经安装好了

[root@VM-0-15-centos ~]# javac
Usage: javac <options> <source files>
where possible options include:
  -g                         Generate all debugging info
  -g:none                    Generate no debugging info
  -g:{lines,vars,source}     Generate only some debugging info
  -nowarn                    Generate no warnings
  -verbose                   Output messages about what the compiler is doing
  -deprecation               Output source locations where deprecated APIs are used
  -classpath <path>          Specify where to find user class files and annotation processors

三、tomcat

　　1、安装：yum在线安装tomcat（-y 代表遇到询问都选 y,这样安装过程中就不需要手动输入y了）

yum -y install tomcat

　　2、查看tomcat服务状态：Active: inactive (dead)  服务处于挂了的状态

[root@VM-0-15-centos tomcat]# systemctl status tomcat
● tomcat.service - Apache Tomcat Web Application Container
   Loaded: loaded (/usr/lib/systemd/system/tomcat.service; disabled; vendor preset: disabled)
   Active: inactive (dead)
[root@VM-0-15-centos tomcat]# 

　　3、启动tomcat服务，查看状态：Active: active (running) 服务运行中

[root@VM-0-15-centos tomcat]# systemctl start tomcat
[root@VM-0-15-centos tomcat]# systemctl status tomcat
● tomcat.service - Apache Tomcat Web Application Container
Loaded: loaded (/usr/lib/systemd/system/tomcat.service; disabled; vendor preset: disabled)
Active: active (running) since Mon 2020-08-10 10:27:53 CST; 9s ago
Main PID: 27930 (java)
CGroup: /system.slice/tomcat.service
└─27930 /usr/lib/jvm/jre/bin/java -classpath /usr/share/tomcat/bin/bootstrap.jar:/usr/share/t...

Aug 10 10:27:54 VM-0-15-centos server[27930]: Aug 10, 2020 10:27:54 AM org.apache.catalina.startup.C...load
Aug 10 10:27:54 VM-0-15-centos server[27930]: INFO: Initialization processed in 515 ms
Aug 10 10:27:54 VM-0-15-centos server[27930]: Aug 10, 2020 10:27:54 AM org.apache.catalina.core.Stan...rnal
Aug 10 10:27:54 VM-0-15-centos server[27930]: INFO: Starting service Catalina
Aug 10 10:27:54 VM-0-15-centos server[27930]: Aug 10, 2020 10:27:54 AM org.apache.catalina.core.Stan...rnal
Aug 10 10:27:54 VM-0-15-centos server[27930]: INFO: Starting Servlet Engine: Apache Tomcat/7.0.76
Aug 10 10:27:54 VM-0-15-centos server[27930]: Aug 10, 2020 10:27:54 AM org.apache.coyote.AbstractPro...tart
Aug 10 10:27:54 VM-0-15-centos server[27930]: INFO: Starting ProtocolHandler ["ajp-bio-8009"]
Aug 10 10:27:54 VM-0-15-centos server[27930]: Aug 10, 2020 10:27:54 AM org.apache.catalina.startup.C...tart
Aug 10 10:27:54 VM-0-15-centos server[27930]: INFO: Server startup in 34 ms
Hint: Some lines were ellipsized, use -l to show in full.
[root@VM-0-15-centos tomcat]# 

　　4、访问：浏览器访问http://服务器公网ip:8080， 就可以打开tomcat的地址了

　　5、配置用户：进入 tomcat 安装目录（cd /usr/share/tomcat），进入 conf 目录，打开 tomcat-users.xml 文件，在 标签下，添加如下配置：

<role rolename="manager-gui"/>
<user username="root" password="root" roles="manager-gui"/>

　　6、tomcat相关命令

停止tomcat服务

systemctl stop tomcat

重启tomcat

systemctl restart tomcat

开机启动

systemctl enable tomcat

查看tomcat状态

systemctl status tomcat

启动tomcat

systemctl start tomcat