云计算Day02

第二天：

卸载之前的jdk，装jdk22版本以及更高版本

卸载方式：（之前下载的jdk1.8.0-161在/etc/profile中已有修改环境变量的命令，卸载时无需修改环境变量）

1.找出之前下载的jdk版本：

[root@one01 ~]# rpm -qa | grep -i java

javapackages-tools-3.4.1-11.el7.noarch

java-1.8.0-openjdk-headless-1.8.0.161-2.b14.el7.x86_64

python-javapackages-3.4.1-11.el7.noarch

tzdata-java-2018c-1.el7.noarch

2.查看之前下载的版本号（目前用的jdk1.8.0_161版本）

[root@one01 ~]# java -version

openjdk version "1.8.0_161"

OpenJDK Runtime Environment (build 1.8.0_161-b14)

OpenJDK 64-Bit Server VM (build 25.161-b14, mixed mode)

3.卸载之前的版本（版本号为上面所查询到的已有的）

[root@one01 ~]# yum -y remove java-1.8.0-openjdk-headless-1.8.0.161-2.b14.el7.x86_64

[root@one01 ~]# java  -version   //卸载完后查看，没有了

-bash: /usr/bin/java: 没有那个文件或目录

4.去官网（Java Downloads | Oracle 中国）上查看自己需要的jdk安装文件，此处我选用的是https://download.oracle.com/java/22/latest/jdk-22_linux-x64_bin.tar.gz

[root@one01 ~]# ls

anaconda-ks.cfg  jdk-22_linux-x64_bin.tar.gz

5.解压

[root@one01 ~]# tar -zxvf jdk-22_linux-x64_bin.tar.gz

[root@one01 ~]# ls

anaconda-ks.cfg  jdk-22.0.1  jdk-22_linux-x64_bin.tar.gz

6.移动jdk文件并查询其路径

[root@one01 ~]# mv jdk-22.0.1/ /usr/local/

[root@one01 ~]# cd /usr/local/

[root@one01 local]# ls

apache-tomcat-10.1.25  bin  games    jdk-22.0.1  lib64    sbin   src

apache-tomcat-9.0.91   etc  include  lib         libexec  share

[root@one01 local]# cd /usr/local/jdk-22.0.1/

[root@one01 jdk-22.0.1]# cd bin/

[root@one01 bin]# pwd

/usr/local/jdk-22.0.1/bin

7.修改环境变量

[root@one01 bin]# vim /etc/profile

export PATH=/usr/local/jdk-22.0.1/bin:$PATH   //末尾添加暴露路径

8.刷新并查看

[root@one01 bin]# source /etc/profile

[root@one01 bin]# java -version

java version "22.0.1" 2024-04-16

Java(TM) SE Runtime Environment (build 22.0.1+8-16)

Java HotSpot(TM) 64-Bit Server VM (build 22.0.1+8-16, mixed mode, sharing)

------------------------------，----------------------------

关闭防火墙systemctl stop firewalld

开启防火墙systemctl start firewalld

开机自启防火墙systemctl enable firewalld

重新启动tomcat与maven

[root@one01 bin]#  cd /usr/local/apache-tomcat-9.0.91/

[root@one01 apache-tomcat-9.0.91]# ./bin/startup.sh   //启动tomcat 

Using CATALINA_BASE:   /usr/local/apache-tomcat-9.0.91

Using CATALINA_HOME:   /usr/local/apache-tomcat-9.0.91

Using CATALINA_TMPDIR: /usr/local/apache-tomcat-9.0.91/temp

Using JRE_HOME:        /usr/local/jdk-22.0.1

Using CLASSPATH:       /usr/local/apache-tomcat-9.0.91/bin/bootstrap.jar:/usr/local/apache-tomcat-9.0.91/bin/tomcat-juli.jar

Using CATALINA_OPTS:   

Tomcat started.

[root@one01 apache-tomcat-9.0.91]# cd /opt apache-maven-3.9.8/bin/

[root@one01 bin]# mvn -v    //启动maven

Apache Maven 3.9.8 (36645f6c9b5079805ea5009217e36f2cffd34256)

Maven home: /opt/apache-maven-3.9.8

Java version: 22.0.1, vendor: Oracle Corporation, runtime: /usr/local/jdk-22.0.1

Default locale: zh_CN, platform encoding: UTF-8

OS name: "linux", version: "3.10.0-862.el7.x86_64", arch: "amd64", family: "unix"

---------------------，-------------------

第二天下午：

1. 下载jdk
2. 解压
3. 解压后文件移动到/usr/local并且改名
4. 找到可执行文件
5. 在profile中配置jdk环境
6. 讲java的可执行文件添加到$PATH的环境变量中

export PATH=/usr/local/maven3/bin/:/usr/local/jdk17/bin/:$PATH

export JAVA_HOME=/usr/local/jdk17/     //红色部分:jdk路径jdk-22.0.1

[root@one01 bin]# vim /etc/profile

export PATH=/usr/local/maven3/bin/:/usr/local/jdk-22.0.1/bin/:$PATH

export JAVA_HOME=/usr/local/ jdk-22.0.1/     //红色部分:jdk路径jdk-22.0.1

[root@one01 bin]# source /etc/profile

[root@one01 bin]# $JAVA_HOME

-bash: /usr/local/jdk-22.0.1/: 是一个目录

查看哪有这个：

[root@one01 bin]# whereis python

python: /usr/bin/python /usr/bin/python2.7 /usr/lib/python2.7 /usr/lib64/python2.7 /etc/python /usr/include/python2.7 /usr/share/man/man1/python.1.gz

[root@one01 bin]# python

Python 2.7.5 (default, Apr 11 2018, 07:36:10)

[GCC 4.8.5 20150623 (Red Hat 4.8.5-28)] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> print("xnjnnc")

xnjnnc

>>> print(2+3)

5

>>>       //quit或者ctrl+z退出

下载python3试试，官网tar包连接：Python Source Releases | Python.org

1. pythonweb
2. 人工智能环境
3. 数据分析

python2

with open(“a.txt”,”wb”)as f:

  f.write(“write”)

------，----------，--------

[root@one01 bin]# yum list|grep python3

[root@one01 bin]# python

Python 2.7.5 (default, Apr 11 2018, 07:36:10)

[GCC 4.8.5 20150623 (Red Hat 4.8.5-28)] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> with open("b.txt","wb") as f:

...       f.write("我，秦始皇，打钱")

>>> import os

>>> os.listdir("./")

['jar', 'jarsigner', 'java', 'javac', 'javadoc', 'javap', 'jcmd', 'jconsole', 'jdb', 'jdeprscan', 'jdeps', 'jfr', 'jhsdb', 'jimage', 'jinfo', 'jlink', 'jmap', 'jmod', 'jpackage', 'jps', 'jrunscript', 'jshell', 'jstack', 'jstat', 'jstatd', 'jwebserver', 'keytool', 'rmiregistry', 'serialver']

>>>