[研究]Java安裝與版本切換 (CentOS 8.4 x64)

[研究]Java安裝與版本切換 (CentOS 8.4 x64)

2021-07-20

CentOS 8.4 提供的 Java 版本，不提供單純的 JRE，都是 JDK。

[john@localhost ~]$ yum list | grep java HdrHistogram-javadoc.noarch 2.1.11-3.module_el8.4.0+721+9e20c0c2 appstream abrt-java-connector.x86_64 1.1.0-16.el8 appstream brlapi-java.x86_64 0.6.7-32.el8 appstream byteman-javadoc.noarch 4.0.4-2.el8 appstream directory-maven-plugin-javadoc.noarch 0.3.1-2.module_el8.4.0+721+9e20c0c2 appstream google-noto-sans-javanese-fonts.noarch 20161022-7.el8.1 appstream icedtea-web-javadoc.noarch 1.8.4-4.el8 appstream jaf-javadoc.noarch 1.2.1-5.module_el8.4.0+721+9e20c0c2 appstream java-1.8.0-openjdk.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-accessibility.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-demo.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-devel.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-headless.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-headless-slowdebug.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-javadoc-zip.noarch 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-slowdebug.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-src.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-11-openjdk.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-demo.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-devel.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-headless.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-javadoc.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-javadoc-zip.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-jmods.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-src.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-static-libs.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-atk-wrapper.x86_64 0.33.2-6.el8 appstream javapackages-filesystem.noarch 5.3.0-1.module_el8.0.0+11+5b8c10bd appstream javapackages-tools.noarch 5.3.0-1.module_el8.0.0+11+5b8c10bd appstream jmc-core-javadoc.noarch 8.0.0-2.module_el8.4.0+721+9e20c0c2 appstream libguestfs-java.x86_64 1:1.40.2-27.module_el8.4.0+783+f8734d30 appstream libguestfs-java-devel.x86_64 1:1.40.2-27.module_el8.4.0+783+f8734d30 appstream libguestfs-javadoc.noarch 1:1.40.2-27.module_el8.4.0+783+f8734d30 appstream lz4-java.x86_64 1.7.1-14.module_el8.4.0+708+63f8a724 appstream lz4-java-javadoc.noarch 1.7.1-14.module_el8.4.0+708+63f8a724 appstream mariadb-java-client.noarch 2.2.5-3.el8 appstream owasp-java-encoder.noarch 1.2.2-3.module_el8.4.0+721+9e20c0c2 appstream owasp-java-encoder-javadoc.noarch 1.2.2-3.module_el8.4.0+721+9e20c0c2 appstream postgresql-jdbc-javadoc.noarch 42.2.3-3.el8_2 appstream subversion-javahl.noarch 1.10.2-4.module_el8.3.0+703+ba2f61b7 appstream systemtap-runtime-java.x86_64 4.4-10.el8 appstream tzdata-java.noarch 2021a-1.el8 appstream [john@localhost ~]$ [john@localhost ~]$ yum list | grep jre [john@localhost ~]$ yum list | grep jdk copy-jdk-configs.noarch 3.7-4.el8 appstream java-1.8.0-openjdk.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-accessibility.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-demo.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-devel.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-headless.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-headless-slowdebug.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-javadoc-zip.noarch 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-slowdebug.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-1.8.0-openjdk-src.x86_64 1:1.8.0.292.b10-1.el8_4 appstream java-11-openjdk.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-demo.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-devel.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-headless.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-javadoc.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-javadoc-zip.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-jmods.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-src.x86_64 1:11.0.11.0.9-2.el8_4 appstream java-11-openjdk-static-libs.x86_64 1:11.0.11.0.9-2.el8_4 appstream [john@localhost ~]$

安裝Java，預設會安裝 Java 8 ( 1.8.0)

[john@localhost ~]$ yum -y install java Error: This command has to be run with superuser privileges (under the root user on most systems). [john@localhost ~]$ sudo yum -y install java [sudo] password for john: Sorry, try again. [sudo] password for john: Last metadata expiration check: -1 day, 17:46:58 ago on Tue 20 Jul 2021 03:48:03 AM EDT. Dependencies resolved. =============================================================================================================================================== Package Architecture Version Repository Size =============================================================================================================================================== Installing: java-1.8.0-openjdk x86_64 1:1.8.0.292.b10-1.el8_4 appstream 335 k Installing dependencies: copy-jdk-configs noarch 3.7-4.el8 appstream 27 k java-1.8.0-openjdk-headless x86_64 1:1.8.0.292.b10-1.el8_4 appstream 34 M javapackages-filesystem noarch 5.3.0-1.module_el8.0.0+11+5b8c10bd appstream 30 k lksctp-tools x86_64 1.0.18-3.el8 baseos 100 k ttmkfdir x86_64 3.0.9-54.el8 appstream 62 k tzdata-java noarch 2021a-1.el8 appstream 192 k xorg-x11-fonts-Type1 noarch 7.5-19.el8 appstream 522 k Enabling module streams: javapackages-runtime 201801 Transaction Summary =============================================================================================================================================== Install 8 Packages Total download size: 35 M Installed size: 119 M Downloading Packages: (1/8): copy-jdk-configs-3.7-4.el8.noarch.rpm 435 kB/s | 27 kB 00:00 (2/8): javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b8c10bd.noarch.rpm 1.6 MB/s | 30 kB 00:00 (3/8): ttmkfdir-3.0.9-54.el8.x86_64.rpm 1.9 MB/s | 62 kB 00:00 (4/8): tzdata-java-2021a-1.el8.noarch.rpm 2.8 MB/s | 192 kB 00:00 (5/8): java-1.8.0-openjdk-1.8.0.292.b10-1.el8_4.x86_64.rpm 1.4 MB/s | 335 kB 00:00 (6/8): xorg-x11-fonts-Type1-7.5-19.el8.noarch.rpm 3.8 MB/s | 522 kB 00:00 (7/8): lksctp-tools-1.0.18-3.el8.x86_64.rpm 309 kB/s | 100 kB 00:00 (8/8): java-1.8.0-openjdk-headless-1.8.0.292.b10-1.el8_4.x86_64.rpm 3.2 MB/s | 34 MB 00:10 ----------------------------------------------------------------------------------------------------------------------------------------------- Total 2.2 MB/s | 35 MB 00:16 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Running scriptlet: copy-jdk-configs-3.7-4.el8.noarch 1/1 Running scriptlet: java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 1/1 Preparing : 1/1 Installing : lksctp-tools-1.0.18-3.el8.x86_64 1/8 Running scriptlet: lksctp-tools-1.0.18-3.el8.x86_64 1/8 Installing : tzdata-java-2021a-1.el8.noarch 2/8 Installing : ttmkfdir-3.0.9-54.el8.x86_64 3/8 Installing : xorg-x11-fonts-Type1-7.5-19.el8.noarch 4/8 Running scriptlet: xorg-x11-fonts-Type1-7.5-19.el8.noarch 4/8 Installing : javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b8c10bd.noarch 5/8 Installing : copy-jdk-configs-3.7-4.el8.noarch 6/8 Installing : java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 7/8 Running scriptlet: java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 7/8 Installing : java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 8/8 Running scriptlet: java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 8/8 Running scriptlet: copy-jdk-configs-3.7-4.el8.noarch 8/8 Running scriptlet: java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 8/8 Verifying : copy-jdk-configs-3.7-4.el8.noarch 1/8 Verifying : java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 2/8 Verifying : java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 3/8 Verifying : javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b8c10bd.noarch 4/8 Verifying : ttmkfdir-3.0.9-54.el8.x86_64 5/8 Verifying : tzdata-java-2021a-1.el8.noarch 6/8 Verifying : xorg-x11-fonts-Type1-7.5-19.el8.noarch 7/8 Verifying : lksctp-tools-1.0.18-3.el8.x86_64 8/8 Installed products updated. Installed: copy-jdk-configs-3.7-4.el8.noarch java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b8c10bd.noarch lksctp-tools-1.0.18-3.el8.x86_64 ttmkfdir-3.0.9-54.el8.x86_64 tzdata-java-2021a-1.el8.noarch xorg-x11-fonts-Type1-7.5-19.el8.noarch Complete! [john@localhost ~]$

測試

[john@localhost ~]$ java -version openjdk version "1.8.0_292" OpenJDK Runtime Environment (build 1.8.0_292-b10) OpenJDK 64-Bit Server VM (build 25.292-b10, mixed mode) [john@localhost ~]$

先安裝 Java 8，再安裝 Java 11 後，測試發先系統仍使用 Java 8

xxx [john@localhost ~]$ sudo yum -y install java-11 Last metadata expiration check: 0:00:45 ago on Mon 19 Jul 2021 09:49:16 PM EDT. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: java-11-openjdk x86_64 1:11.0.11.0.9-2.el8_4 appstream 260 k Installing dependencies: java-11-openjdk-headless x86_64 1:11.0.11.0.9-2.el8_4 appstream 39 M Transaction Summary ================================================================================ Install 2 Packages Total download size: 40 M Installed size: 171 M Downloading Packages: (1/2): java-11-openjdk-11.0.11.0.9-2.el8_4.x86_ 2.5 MB/s | 260 kB 00:00 (2/2): java-11-openjdk-headless-11.0.11.0.9-2.e 2.2 MB/s | 39 MB 00:18 -------------------------------------------------------------------------------- Total 2.1 MB/s | 40 MB 00:19 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Running scriptlet: java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 1/1 Preparing : 1/1 Installing : java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 1/2 Running scriptlet: java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 1/2 Installing : java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 2/2 Running scriptlet: java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 2/2 Verifying : java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 1/2 Verifying : java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 2/2 Installed products updated. Installed: java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_64 Complete! [john@localhost ~]$ java -version openjdk version "1.8.0_292" OpenJDK Runtime Environment (build 1.8.0_292-b10) OpenJDK 64-Bit Server VM (build 25.292-b10, mixed mode) [john@localhost ~]$

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VM快照還原

先安裝  Java 11

xxx [john@localhost ~]$ sudo yum install -y java-11-openjdk CentOS Linux 8 - AppStream 2.4 MB/s | 8.1 MB 00:03 CentOS Linux 8 - BaseOS 894 kB/s | 3.6 MB 00:04 CentOS Linux 8 - Extras 14 kB/s | 9.8 kB 00:00 Last metadata expiration check: -1 day, 16:00:04 ago on Tue 20 Jul 2021 05:41:40 AM EDT. Dependencies resolved. ================================================================================ Package Arch Version Repo Size ================================================================================ Installing: java-11-openjdk x86_64 1:11.0.11.0.9-2.el8_4 appstream 260 k Installing dependencies: copy-jdk-configs noarch 3.7-4.el8 appstream 27 k java-11-openjdk-headless x86_64 1:11.0.11.0.9-2.el8_4 appstream 39 M javapackages-filesystem noarch 5.3.0-1.module_el8.0.0+11+5b8c10bd appstream 30 k lksctp-tools x86_64 1.0.18-3.el8 baseos 100 k ttmkfdir x86_64 3.0.9-54.el8 appstream 62 k tzdata-java noarch 2021a-1.el8 appstream 192 k xorg-x11-fonts-Type1 noarch 7.5-19.el8 appstream 522 k Enabling module streams: javapackages-runtime 201801 Transaction Summary ================================================================================ Install 8 Packages Total download size: 41 M Installed size: 173 M Downloading Packages: (1/8): copy-jdk-configs-3.7-4.el8.noarch.rpm 1.0 MB/s | 27 kB 00:00 (2/8): javapackages-filesystem-5.3.0-1.module_e 2.3 MB/s | 30 kB 00:00 (3/8): ttmkfdir-3.0.9-54.el8.x86_64.rpm 2.5 MB/s | 62 kB 00:00 (4/8): java-11-openjdk-11.0.11.0.9-2.el8_4.x86_ 2.9 MB/s | 260 kB 00:00 (5/8): xorg-x11-fonts-Type1-7.5-19.el8.noarch.r 4.7 MB/s | 522 kB 00:00 (6/8): tzdata-java-2021a-1.el8.noarch.rpm 1.1 MB/s | 192 kB 00:00 (7/8): lksctp-tools-1.0.18-3.el8.x86_64.rpm 389 kB/s | 100 kB 00:00 (8/8): java-11-openjdk-headless-11.0.11.0.9-2.e 5.2 MB/s | 39 MB 00:07 -------------------------------------------------------------------------------- Total 4.4 MB/s | 41 MB 00:09 warning: /var/cache/dnf/appstream-a520ed22b0a8a736/packages/copy-jdk-configs-3.7-4.el8.noarch.rpm: Header V3 RSA/SHA256 Signature, key ID 8483c65d: NOKEY CentOS Linux 8 - AppStream 1.6 MB/s | 1.6 kB 00:00 Importing GPG key 0x8483C65D: Userid : "CentOS (CentOS Official Signing Key) <security@centos.org>" Fingerprint: 99DB 70FA E1D7 CE22 7FB6 4882 05B5 55B3 8483 C65D From : /etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial Key imported successfully Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Running scriptlet: copy-jdk-configs-3.7-4.el8.noarch 1/1 Running scriptlet: java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 1/1 Preparing : 1/1 Installing : lksctp-tools-1.0.18-3.el8.x86_64 1/8 Running scriptlet: lksctp-tools-1.0.18-3.el8.x86_64 1/8 Installing : tzdata-java-2021a-1.el8.noarch 2/8 Installing : ttmkfdir-3.0.9-54.el8.x86_64 3/8 Installing : xorg-x11-fonts-Type1-7.5-19.el8.noarch 4/8 Running scriptlet: xorg-x11-fonts-Type1-7.5-19.el8.noarch 4/8 Installing : javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b 5/8 Installing : copy-jdk-configs-3.7-4.el8.noarch 6/8 Installing : java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 7/8 Running scriptlet: java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 7/8 Installing : java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 8/8 Running scriptlet: java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 8/8 Running scriptlet: copy-jdk-configs-3.7-4.el8.noarch 8/8 Running scriptlet: java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 8/8 Verifying : copy-jdk-configs-3.7-4.el8.noarch 1/8 Verifying : java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 2/8 Verifying : java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_6 3/8 Verifying : javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b 4/8 Verifying : ttmkfdir-3.0.9-54.el8.x86_64 5/8 Verifying : tzdata-java-2021a-1.el8.noarch 6/8 Verifying : xorg-x11-fonts-Type1-7.5-19.el8.noarch 7/8 Verifying : lksctp-tools-1.0.18-3.el8.x86_64 8/8 Installed products updated. Installed: copy-jdk-configs-3.7-4.el8.noarch java-11-openjdk-1:11.0.11.0.9-2.el8_4.x86_64 java-11-openjdk-headless-1:11.0.11.0.9-2.el8_4.x86_64 javapackages-filesystem-5.3.0-1.module_el8.0.0+11+5b8c10bd.noarch lksctp-tools-1.0.18-3.el8.x86_64 ttmkfdir-3.0.9-54.el8.x86_64 tzdata-java-2021a-1.el8.noarch xorg-x11-fonts-Type1-7.5-19.el8.noarch Complete! [john@localhost ~]$

測試

xxx [john@localhost ~]$ java -version openjdk version "11.0.11" 2021-04-20 LTS OpenJDK Runtime Environment 18.9 (build 11.0.11+9-LTS) OpenJDK 64-Bit Server VM 18.9 (build 11.0.11+9-LTS, mixed mode, sharing) [john@localhost ~]$

再安裝 Java 8

xxx [john@localhost ~]$ sudo yum -y install java Last metadata expiration check: -1 day, 16:01:41 ago on Tue 20 Jul 2021 05:41:40 AM EDT. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: java-1.8.0-openjdk x86_64 1:1.8.0.292.b10-1.el8_4 appstream 335 k Installing dependencies: java-1.8.0-openjdk-headless x86_64 1:1.8.0.292.b10-1.el8_4 appstream 34 M Transaction Summary ================================================================================ Install 2 Packages Total download size: 34 M Installed size: 118 M Downloading Packages: (1/2): java-1.8.0-openjdk-1.8.0.292.b10-1.el8_4 2.8 MB/s | 335 kB 00:00 (2/2): java-1.8.0-openjdk-headless-1.8.0.292.b1 6.1 MB/s | 34 MB 00:05 -------------------------------------------------------------------------------- Total 5.5 MB/s | 34 MB 00:06 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Running scriptlet: java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4. 1/1 Preparing : 1/1 Installing : java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4. 1/2 Running scriptlet: java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4. 1/2 Installing : java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 2/2 Running scriptlet: java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 2/2 Verifying : java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 1/2 Verifying : java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4. 2/2 Installed products updated. Installed: java-1.8.0-openjdk-1:1.8.0.292.b10-1.el8_4.x86_64 java-1.8.0-openjdk-headless-1:1.8.0.292.b10-1.el8_4.x86_64 Complete! [john@localhost ~]$

測試，是 Java 8

[john@localhost ~]$ java -version openjdk version "1.8.0_292" OpenJDK Runtime Environment (build 1.8.0_292-b10) OpenJDK 64-Bit Server VM (build 25.292-b10, mixed mode) [john@localhost ~]$

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先安裝 Java 8，再安裝 Java 11 後，測試發先系統仍使用 Java 8。

先安裝 Java 11，再安裝 Java 8 後，測試發先系統改用新安裝的Java 8。

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切換版本

強行指定系統使用的 Java 版本

[john@localhost ~]$ alternatives --config java There are 2 programs which provide 'java'. Selection Command ----------------------------------------------- 1 java-11-openjdk.x86_64 (/usr/lib/jvm/java-11-openjdk-11.0.11.0.9-2.el8_4.x86_64/bin/java) *+ 2 java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.292.b10-1.el8_4.x86_64/jre/bin/java) Enter to keep the current selection[+], or type selection number: 1 failed to create /var/lib/alternatives/java.new: Permission denied [john@localhost ~]$ sudo alternatives --config java There are 2 programs which provide 'java'. Selection Command ----------------------------------------------- 1 java-11-openjdk.x86_64 (/usr/lib/jvm/java-11-openjdk-11.0.11.0.9-2.el8_4.x86_64/bin/java) *+ 2 java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.292.b10-1.el8_4.x86_64/jre/bin/java) Enter to keep the current selection[+], or type selection number: 1 [john@localhost ~]$ java -version openjdk version "11.0.11" 2021-04-20 LTS OpenJDK Runtime Environment 18.9 (build 11.0.11+9-LTS) OpenJDK 64-Bit Server VM 18.9 (build 11.0.11+9-LTS, mixed mode, sharing) [john@localhost ~]$

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