1、查找java相关的列表
yum -y list java*
[root@10-60-140-218 tools]# yum -y list java* Loaded plugins: fastestmirror, langpacks, versionlock Loading mirror speeds from cached hostfile Excluding 1 update due to versionlock (use "yum versionlock status" to show it) Installed Packages java-1.8.0-openjdk.x86_64 1:1.8.0.312.b07-1.el7_9 @updates java-1.8.0-openjdk-devel.x86_64 1:1.8.0.312.b07-1.el7_9 @updates java-1.8.0-openjdk-headless.x86_64 1:1.8.0.312.b07-1.el7_9 @updates javapackages-tools.noarch 3.4.1-11.el7 @base Available Packages java-1.6.0-openjdk.x86_64 1:1.6.0.41-1.13.13.1.el7_3 base java-1.6.0-openjdk-demo.x86_64 1:1.6.0.41-1.13.13.1.el7_3 base java-1.6.0-openjdk-devel.x86_64 1:1.6.0.41-1.13.13.1.el7_3 base java-1.6.0-openjdk-javadoc.x86_64 1:1.6.0.41-1.13.13.1.el7_3 base java-1.6.0-openjdk-src.x86_64 1:1.6.0.41-1.13.13.1.el7_3 base java-1.7.0-openjdk.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-accessibility.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-demo.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-devel.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-headless.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-javadoc.noarch 1:1.7.0.261-2.6.22.2.el7_8 base java-1.7.0-openjdk-src.x86_64 1:1.7.0.261-2.6.22.2.el7_8 base java-1.8.0-openjdk.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-accessibility.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-accessibility.x86_64 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-demo.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-demo.x86_64 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-devel.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-headless.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-javadoc-zip.noarch 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-src.i686 1:1.8.0.312.b07-1.el7_9 updates java-1.8.0-openjdk-src.x86_64 1:1.8.0.312.b07-1.el7_9 updates java-11-openjdk.i686 1:11.0.13.0.8-1.el7_9
或者
yum search jdk
[root@10-60-140-218 tools]# yum search jdk Loaded plugins: fastestmirror, langpacks, versionlock Loading mirror speeds from cached hostfile Excluding 1 update due to versionlock (use "yum versionlock status" to show it) ================================================= N/S matched: jdk ================================================== copy-jdk-configs.noarch : JDKs configuration files copier java-1.6.0-openjdk.x86_64 : OpenJDK Runtime Environment java-1.6.0-openjdk-demo.x86_64 : OpenJDK Demos java-1.6.0-openjdk-devel.x86_64 : OpenJDK Development Environment java-1.6.0-openjdk-javadoc.x86_64 : OpenJDK API documentation java-1.6.0-openjdk-src.x86_64 : OpenJDK Source Bundle java-1.7.0-openjdk.x86_64 : OpenJDK Runtime Environment java-1.7.0-openjdk-accessibility.x86_64 : OpenJDK accessibility connector java-1.7.0-openjdk-demo.x86_64 : OpenJDK Demos java-1.7.0-openjdk-devel.x86_64 : OpenJDK Development Environment java-1.7.0-openjdk-headless.x86_64 : The OpenJDK runtime environment without audio and video support java-1.7.0-openjdk-javadoc.noarch : OpenJDK API documentation java-1.7.0-openjdk-src.x86_64 : OpenJDK Source Bundle java-1.8.0-openjdk.i686 : OpenJDK Runtime Environment 8 java-1.8.0-openjdk.x86_64 : OpenJDK 8 Runtime Environment java-1.8.0-openjdk-accessibility.i686 : OpenJDK accessibility connector java-1.8.0-openjdk-accessibility.x86_64 : OpenJDK accessibility connector java-1.8.0-openjdk-demo.i686 : OpenJDK Demos 8 java-1.8.0-openjdk-demo.x86_64 : OpenJDK 8 Demos java-1.8.0-openjdk-devel.i686 : OpenJDK Development Environment 8 java-1.8.0-openjdk-devel.x86_64 : OpenJDK 8 Development Environment java-1.8.0-openjdk-headless.i686 : OpenJDK Headless Runtime Environment 8 java-1.8.0-openjdk-headless.x86_64 : OpenJDK 8 Headless Runtime Environment java-1.8.0-openjdk-javadoc.noarch : OpenJDK 8 API documentation java-1.8.0-openjdk-javadoc-zip.noarch : OpenJDK 8 API documentation compressed in a single archive java-1.8.0-openjdk-src.i686 : OpenJDK Source Bundle 8 java-1.8.0-openjdk-src.x86_64 : OpenJDK 8 Source Bundle java-11-openjdk.i686 : OpenJDK Runtime Environment 11
2、安装jdk
yum install java-1.8.0-openjdk.x86_64
3、完成安装后验证
java -version
[root@10-60-140-218 jvm]# java -version openjdk version "1.8.0_312" OpenJDK Runtime Environment (build 1.8.0_312-b07) OpenJDK 64-Bit Server VM (build 25.312-b07, mixed mode)
4、通过yum安装的默认路径为：/usr/lib/jvm
[root@10-60-140-218 tools]# cd /usr/lib/jvm [root@10-60-140-218 jvm]# ll total 0 lrwxrwxrwx 1 root root 26 Dec 23 09:49 java -> /etc/alternatives/java_sdk lrwxrwxrwx 1 root root 32 Dec 23 09:49 java-1.8.0 -> /etc/alternatives/java_sdk_1.8.0 lrwxrwxrwx 1 root root 40 Dec 23 09:49 java-1.8.0-openjdk -> /etc/alternatives/java_sdk_1.8.0_openjdk drwxr-xr-x 7 root root 135 Dec 23 09:49 java-1.8.0-openjdk-1.8.0.312.b07-1.el7_9.x86_64 lrwxrwxrwx 1 root root 34 Dec 23 09:49 java-openjdk -> /etc/alternatives/java_sdk_openjdk lrwxrwxrwx 1 root root 21 Dec 22 16:22 jre -> /etc/alternatives/jre lrwxrwxrwx 1 root root 27 Dec 22 16:22 jre-1.8.0 -> /etc/alternatives/jre_1.8.0 lrwxrwxrwx 1 root root 35 Dec 22 16:22 jre-1.8.0-openjdk -> /etc/alternatives/jre_1.8.0_openjdk lrwxrwxrwx 1 root root 51 Dec 22 16:22 jre-1.8.0-openjdk-1.8.0.312.b07-1.el7_9.x86_64 -> java-1.8.0-openjdk-1.8.0.312.b07-1.el7_9.x86_64/jre lrwxrwxrwx 1 root root 29 Dec 22 16:22 jre-openjdk -> /etc/alternatives/jre_openjdk
5、将jdk的安装路径加入到JAVA_HOME
vi /etc/profile
在文件最后加入：
#set java environment JAVA_HOME=/usr/lib/jvm/jre-1.8.0-openjdk PATH=$PATH:$JAVA_HOME/bin CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools-1.8.0.jar export JAVA_HOME CLASSPATH PATH
修改/etc/profile之后让其生效
. /etc/profile （注意 . 之后应有一个空格）
这时候随意创建 一个 Test.java文件
public class Test {
public static void main(String args[]) {
System.out.println("A new jdk test !");
}
}
执行javac编译时 出现
[root@10-60-140-218 home]# javac /home/tools/Test.java bash:javac:command not found
这种情况
①可能是 没有 tools.jar 包
我选择的是这个 1.8.0.jar
tools-1.8.0.jar.zip-Linux文档类资源-CSDN下载
可能在之前的配置中能看到 最终版本 vi /etc/profile
②还有就是
安装开发环境不安装则无法使用javac
[root@10-60-140-218 home]# yum install java-1.8.0-openjdk-devel.x86_64 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile Resolving Dependencies --> Running transaction check ---> Package java-1.8.0-openjdk-devel.x86_64 1:1.8.0.292.b10-1.el7_9 will be installed --> Finished Dependency Resolution Dependencies Resolved ================================================================================================================================================================================================================================================= Package Arch Version Repository Size ================================================================================================================================================================================================================================================= Installing: java-1.8.0-openjdk-devel x86_64 1:1.8.0.292.b10-1.el7_9 updates 9.8 M Transaction Summary ================================================================================================================================================================================================================================================= Install 1 Package Total download size: 9.8 M Installed size: 40 M Is this ok [y/d/N]: y Downloading packages: java-1.8.0-openjdk-devel-1.8.0.292.b10-1.el7_9.x86_64.rpm | 9.8 MB 00:00:00 Running transaction check Running transaction test Transaction test succeeded Running transaction Installing : 1:java-1.8.0-openjdk-devel-1.8.0.292.b10-1.el7_9.x86_64 1/1 Verifying : 1:java-1.8.0-openjdk-devel-1.8.0.292.b10-1.el7_9.x86_64 1/1 Installed: java-1.8.0-openjdk-devel.x86_64 1:1.8.0.292.b10-1.el7_9 Complete!
再次检查 配置 vi /etc/profile 文件
#set java environment JAVA_HOME=/usr/lib/jvm/jre-1.8.0-openjdk PATH=$PATH:$JAVA_HOME/bin CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools-1.8.0.jar export JAVA_HOME CLASSPATH PATH
. /etc/profile
或者 source /etc/profile
生效配置文件;
[root@10-60-140-218 tools]# source /etc/profile
必须reboot 重启下linux系统; 不然不保证能生效.
重启后测试下 javac
[root@10-60-140-218 tools]# javac Usage: javacwhere 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 Specify where to find user class files and annotation processors -cp Specify where to find user class files and annotation processors -sourcepath Specify where to find input source files -bootclasspath Override location of bootstrap class files -extdirs Override location of installed extensions -endorseddirs Override location of endorsed standards path -proc:{none,only} Control whether annotation processing and/or compilation is done. -processor [, , ...] Names of the annotation processors to run; bypasses default discovery process -processorpath Specify where to find annotation processors -parameters Generate metadata for reflection on method parameters -d Specify where to place generated class files -s Specify where to place generated source files -h Specify where to place generated native header files -implicit:{none,class} Specify whether or not to generate class files for implicitly referenced files -encoding Specify character encoding used by source files -source Provide source compatibility with specified release -target Generate class files for specific VM version -profile Check that API used is available in the specified profile -version Version information -help Print a synopsis of standard options -Akey[=value] Options to pass to annotation processors -X Print a synopsis of nonstandard options -J Pass directly to the runtime system -Werror Terminate compilation if warnings occur @ Read options and filenames from file
[root@10-60-140-218 home]# javac /home/tools/Test.java [root@10-60-140-218 home]# java /home/tools/Test.java Error: Could not find or load main class .home.tools.Test.java
出现:Error: Could not find or load main class .home.tools.Test.java 不用慌
[root@10-60-140-218 home]# cd tools/ [root@10-60-140-218 tools]# ll total 16 drwxr-xr-x 7 root root 244 Dec 20 15:21 1 drwxr-xr-x 2 root root 46 Dec 23 09:19 jar -rwxrwxrwx 1 root root 315 Dec 22 09:10 nginx_start.sh -rw-r--r-- 1 root root 418 Dec 23 09:53 Test.class -rw-r--r-- 1 root root 127 Dec 22 16:35 Test.java [root@10-60-140-218 tools]# java Test A new jdk test !
这是有网络的情况下 可以完成.
无网环境还没尝试过 有机会恢复机器 试一次
参考资料进行操作:
linux安装java步骤 - 海岛拾贝 - 博客园
centOS7 yum install java-1.8.0-openjdk_zh452647457的博客-CSDN博客
如有侵权 请告知
