SerwerWeb.pl

Poniższy poradnik opisuje instalację Javy w kilku wersjach : Oracle Java 8, OpenJDK 8, OpenJDK 11
Na serwerze z systemem Centos 8.
Całość sprowadza się do wykonania kilku komend.

Na początek dokonamy przeszukania repo.
Całość wykonamy poleceniem:

dnf search jdk

Otrzymamy wynik podobny do tego:

Last metadata expiration check: 1:23:41 ago on Wednesday 30 December 2019 02:23:23 AM EST.

========================================================= Summary & Name Matched: jdk =========================================================
java-11-openjdk-demo.x86_64 : OpenJDK Demos 11
java-1.8.0-openjdk-demo.x86_64 : OpenJDK Demos 8
java-11-openjdk-jmods.x86_64 : JMods for OpenJDK 11
java-11-openjdk-src.x86_64 : OpenJDK Source Bundle 11
java-1.8.0-openjdk-src.x86_64 : OpenJDK Source Bundle 8
java-11-openjdk.x86_64 : OpenJDK Runtime Environment 11
copy-jdk-configs.noarch : JDKs configuration files copier
java-1.8.0-openjdk.x86_64 : OpenJDK Runtime Environment 8
java-11-openjdk-javadoc.x86_64 : OpenJDK 11 API documentation
java-1.8.0-openjdk-javadoc.noarch : OpenJDK 8 API documentation
java-11-openjdk-devel.x86_64 : OpenJDK Development Environment 11
java-1.8.0-openjdk-devel.x86_64 : OpenJDK Development Environment 8
java-11-openjdk-headless.x86_64 : OpenJDK Headless Runtime Environment 11
java-1.8.0-openjdk-accessibility.x86_64 : OpenJDK 8 accessibility connector
java-1.8.0-openjdk-headless.x86_64 : OpenJDK Headless Runtime Environment 8
java-11-openjdk-javadoc-zip.x86_64 : OpenJDK 11 API documentation compressed in a single archive
java-1.8.0-openjdk-javadoc-zip.noarch : OpenJDK 8 API documentation compressed in a single archive
============================================================ Summary Matched: jdk =============================================================
icedtea-web.noarch : Additional Java components for OpenJDK - Java browser plug-in and Web Start implementation

Instalacja OpenJDK 11

dnf install java-11-openjdk-devel.x86_64

Wersję javy możemy sprawdzić poleceniem:

java -version

Poniżej wynik:

openjdk version "11.0.5" 2019-10-15 LTS
OpenJDK Runtime Environment 18.9 (build 11.0.5+10-LTS)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.5+10-LTS, mixed mode, sharing)

Instalacja OpenJDK 8

dnf install java-1.8.0-openjdk-devel

Sprawdzenie wersji:

java -version

Wynik:

openjdk version "1.8.0_232"
OpenJDK Runtime Environment (build 1.8.0_232-b09)
OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode)

Aby przełączyć się między wersjami Java wykonujemy polecenie:

alternatives --config java

I wybieramy wersję odpowiednim numerem:

There are 2 programs which provide 'java'.

  Selection    Command
-----------------------------------------------
   1           java-11-openjdk.x86_64 (/usr/lib/jvm/java-11-openjdk-11.0.5.10-0.el8_0.x86_64/bin/java)
*+ 2           java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.232.b09-0.el8_0.x86_64/jre/bin/java)

Enter to keep the current selection[+], or type selection number: 1

Instalacja Oracle Java 8

dnf localinstall jdk-8u231-linux-x64.rpm

No i standardowo sprawdzenie wersji:

java -version

java version "1.8.0_231"
Java(TM) SE Runtime Environment (build 1.8.0_231-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.231-b11, mixed mode)