detlef@detlef:~$ date Do 17. Jul 16:21:47 CEST 2014 detlef@detlef:~$ detlef@detlef:~/$ uname -a Linux detlef 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u1 x86_64 GNU/Linux detlef@detlef:~$
root@detlef:~> java -version java version "1.7.0_45" Java(TM) SE Runtime Environment (build 1.7.0_45-b18) Java HotSpot(TM) 64-Bit Server VM (build 24.45-b08, mixed mode) root@detlef:~/$OK, also noch kein Java 8
Ausschnitt der Oracleseite Installation of the 64-bit JDK on Linux Platforms This procedure installs the Java Development Kit (JDK) for 64-bit Linux, using an archive binary file (.tar.gz). These instructions use the following file: jdk-8uversion-linux-x64.tar.gz Download the file. Before the file can be downloaded, you must accept the license agreement. The archive binary can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JDK into the system location. Change directory to the location where you would like the JDK to be installed, then move the .tar.gz archive binary to the current directory. Unpack the tarball and install the JDK. % tar zxvf jdk-8uversion-linux-x64.tar.gz The Java Development Kit files are installed in a directory called jdk1.8.0_version in the current directory. Delete the .tar.gz file if you want to save disk space.
Wenn man nur sporadisch als sysadmin fungiert, da die Hauptsache die Entwicklung ist, muss man erst einmal ermitteln wo Java installiert ist.
root@detlef:~> whereis java java: /usr/bin/java /usr/bin/X11/java /usr/share/java /usr/share/man/man1/java.1.gz root@detlef:~> ll /usr/bin/java lrwxrwxrwx 1 root root 22 Jan 2 2013 /usr/bin/java -> /etc/alternatives/java root@detlef:~> ll /etc/alternatives/java lrwxrwxrwx 1 root root 37 Nov 28 2013 /etc/alternatives/java -> /usr/lib/jvm/jdk1.7.0_45/jre/bin/java
root@detlef:~> cd /usr/lib/jvm root@detlef:/usr/lib/jvm> root@detlef:~> ll /usr/lib/jvm insgesamt 12 lrwxrwxrwx 1 root root 11 Nov 28 2013 default-java -> jdk1.7.0_45 lrwxrwxrwx 1 root root 20 Okt 17 2012 java-1.6.0-openjdk-amd64 -> java-6-openjdk-amd64 drwxr-xr-x 5 root root 47 Jan 2 2013 java-6-openjdk-amd64 drwxr-xr-x 3 root root 16 Jan 2 2013 java-6-openjdk-common drwxr-xr-x 5 root root 36 Jan 2 2013 java-7-openjdk-amd64 drwxr-xr-x 8 uucp 143 4096 Nov 28 2013 jdk1.7.0_45 drwxr-xr-x 6 detlef detlef 4096 Okt 8 2013 jre1.7.0_45
root@detlef:/usr/lib/jvm> ls -l ~detlef/download/java insgesamt 600016 -rw-r--r-- 1 detlef detlef 21220755 Nov 28 2013 javafx_samples-2_2_45-linux.zip -rw-r--r-- 1 detlef detlef 96272413 Mai 8 2013 jdk-7u21-linux-x64.tar.gz -rw-r--r-- 1 detlef detlef 33617920 Nov 28 2013 jdk-7u45-linux-x64-demos.tar -rw-r--r-- 1 detlef detlef 138094686 Nov 28 2013 jdk-7u45-linux-x64.tar.gz -rw-r--r-- 1 detlef detlef 159019376 Jul 16 19:34 jdk-8u11-linux-x64.tar.gz -rw-r--r-- 1 detlef detlef 46842143 Nov 28 2013 jre-7u45-linux-x64.tar.gz root@detlef:/usr/lib/jvm> md5sum ~detlef/download/java/jdk-8u11-linux-x64.tar.gz 13ee1d0bf6baaf2b119115356f234a48 /home/detlef/download/java/jdk-8u11-linux-x64.tar.gz root@detlef:/usr/lib/jvm> root@detlef:/usr/lib/jvm>
root@detlef:/usr/lib/jvm> tar -tvzf ~detlef/download/java/jdk-8u11-linux-x64.tar.gz Den Output habe ich mir und Ihnen erspart, wenn sie die Option v (verbose) weglassen kommt auch keiner. root@detlef:/usr/lib/jvm> tar -xvzf ~detlef/download/java/jdk-8u11-linux-x64.tar.gz
root@detlef:/usr/lib/jvm> ll insgesamt 16 lrwxrwxrwx 1 root root 11 Nov 28 2013 default-java -> jdk1.7.0_45 lrwxrwxrwx 1 root root 20 Okt 17 2012 java-1.6.0-openjdk-amd64 -> java-6-openjdk-amd64 drwxr-xr-x 5 root root 47 Jan 2 2013 java-6-openjdk-amd64 drwxr-xr-x 3 root root 16 Jan 2 2013 java-6-openjdk-common drwxr-xr-x 8 uucp 143 4096 Nov 28 2013 jdk1.7.0_45 drwxr-xr-x 8 uucp 143 4096 Jun 17 02:40 jdk1.8.0_11 drwxr-xr-x 6 detlef detlef 4096 Okt 8 2013 jre1.7.0_45
root@detlef:/usr/lib/jvm> rm default-java root@detlef:/usr/lib/jvm> ln -s jdk1.8.0_11 default-java root@detlef:/usr/lib/jvm> ll dk1.8.0_11 default-java lrwxrwxrwx 1 root root 11 Jul 16 19:50 default-java -> jdk1.8.0_11
root@detlef:/usr/lib/jvm> java -version java version "1.7.0_45" Java(TM) SE Runtime Environment (build 1.7.0_45-b18) Java HotSpot(TM) 64-Bit Server VM (build 24.45-b08, mixed mode)OK: da fehlt noch was der Link in alternatives muss auch noch umgesetzt werden
root@detlef:/usr/lib/jvm> ll /etc/alternatives/java lrwxrwxrwx 1 root root 37 Nov 28 2013 /etc/alternatives/java -> /usr/lib/jvm/jdk1.7.0_45/jre/bin/java root@detlef:/usr/lib/jvm> cd /etc/alternatives root@detlef:/etc/alternatives> rm java root@detlef:/etc/alternatives> ln -s /usr/lib/jvm/jdk1.8.0_11/jre/bin/java java root@detlef:/etc/alternatives> ll java lrwxrwxrwx 1 root root 37 Jul 16 19:56 java -> /usr/lib/jvm/jdk1.8.0_11/jre/bin/java root@detlef:/etc/alternatives> java -version java version "1.8.0_11" Java(TM) SE Runtime Environment (build 1.8.0_11-b12) Java HotSpot(TM) 64-Bit Server VM (build 25.11-b03, mixed mode) root@detlef:/etc/alternatives>OK: jetzt sollte alles klar sein oder?
less ~username/.bashrc zeigt unter anderem export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_45/bin/javadas sollte geändert werden auf
export JAVA_HOME=/usr/lib/jvm/jdk1.8.0_11/bin/java