I tried to downgrade java version.
If I use apt-get install sun-java6-jdk on Ubuntu, it will install java version 1.6.26 .
What I want is java 1.6.20. How can I downgrade java?
Java on Linux doesn't need to be installed as root. You can install as many different Java versions you want on Linux, either in separate user accounts or in a single account.
I do it all the time (switching from one Java version to another) to test on various versions of the JVM.
Changing your Java version can be as simple as this:
... $ which java
/home/b/jdk1.5.0_22/bin/java
... $ export PATH=/home/b/jdk1.6.0_25/bin:$PATH
... $ which java
/home/b/jdk1.6.0_25/bin/java
To fetch an old version, go to the "Oracle Java Archive" page (Google if link becomes broken):
http://www.oracle.com/technetwork/java/archive-139210.html
Then pick your poison. I download the .bin, chmod +x it and then I extract the Java version I want from the .tgz.
Then I simply set the PATH and I'm usually good to go.
I run my IDE (IntelliJ IDEA) using one Java version, I typically compile using another JDK and I test on several JVMs.
All this from the same user account.
So it's not as if you had to install "one" Java version on a Linux system...
Now, concretely, if I were you, I'd simply remove all traces from Java while being root, and then I'd download the old version I need from the Oracle Java Archive.
like tactical coder said, you can install as many versions as you want, to switch the current version just run:
sudo update-alternatives --config java
And select the desired version.
If you wish, run it for javac and javaws:
sudo update-alternatives --config javac
sudo update-alternatives --config javaws
Source:
https://askubuntu.com/questions/56104/how-can-i-install-sun-oracles-proprietary-java-jdk-6-7-8-or-jre
Follow these steps to downgrade JAVA here[JAVA14 to JAVA8]:
sudo apt-get update
sudo apt-get install openjdk-8-jdk
sudo update-alternatives --config javac
Now Select the version of JDK
sudo update-alternatives --config java
Now Select the version of JRE
DONE
Check if it is downgraded by
java -version
You can download it from the archive section for Java SE 6.
$sudo apt-get install openjdk-8-jre (replace with the version you want to install)
$sudo update-alternatives --config java
{will get the option to choose the alternative java on your machine}
select the one you want to use as default
$java -version
Check the java version
I find Jenv to be the easiest way to switch between Java versions. You can set a Java version globally, or you can set it so that certain directories will use a specified version of Java.
See their website
once installed with Homebrew or cloned from github its as easy as:
jenv add /path/to/java1.6.20/home
jenv global 1.6.20
Related
My current java version is 11.0.12 . I want to install 11.0.13 so I tried with update-alternatives --config java but there is no 13 version.
I also check with installable java version by apt search "OpenJDK" , it show
openjdk-11-jdk 11.0.12
openjdk-8-jdk 8u312
So I don't know how to find 11.0.13 installer package ?
PS - I don't want to install by local downloaded file.
update-alternatives --config java command only works when you have different Java major versions installed in different paths, such as a jdk8 and an 11.
Try updating your repository with sudo apt update and then check with apt list openjdk-11-jdk.
What version of Ubuntu do you have?
I am trying to install the latest version of Java in my Linux machine, but I am unable to do so.
Steps I followed:
Downloaded the latest Java tar ball.
Copied into /usr/lib/jvm and untared it.
Adding in to environment variable (export JAVA_HOME=/usr/lib/javm/jdk1.7.0_80, export PATH=$PATH:$JAVA_HOME/bin).
When I try to change the default Java version, the installed one is
not coming ($ update-alternatives –-config java).
How do I resolve this? I have followed many links, but nothing helps.
You will also have to "install" the new Java software to /etc/alternatives/, in order to select it:
sudo update-alternatives --install /usr/bin/java java /usr/lib/javm/jdk1.7.0_80/jre/bin/java 2000
I have a Linux box on which Java 1.7 is installed:
#java -version
java version "1.7.0_09-icedtea"
OpenJDK Runtime Environment (rhel-2.3.4.1.el6_3-x86_64)
OpenJDK 64-Bit Server VM (build 23.2-b09, mixed mode)
But for some new tool I need to install the jdk-8u45-linux-x64.tar.gz
So how can I remove old one and install the new one?
To remove OpenJDK (the one you've already installed)
sudo apt-get purge openjdk-\*
Make a new directory for your new JDK
sudo mkdir -p /usr/local/java
Copy the file to the directory (you should be in that file path)
sudo cp -r jdk-8u45-linux-x64.tar.gz /usr/local/java/
Extract the file
sudo tar xvzf jdk-8u45-linux-x64.tar.gz
You should add this to your PATH now. To do that:
a. Open /etc/profile : sudo gedit /etc/profile
b. Scroll down (the end) and add the path where your jdk was installed
JAVA_HOME=/usr/local/java/jdk1.8.0_45
PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
export JAVA_HOME
export PATH
Save and exit
Inform your Linux system where your Oracle Java JDK/JRE is located.
a. Notify the system that Oracle Java JRE is available for use
sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.8.0_45/bin/java" 1
b. Notify the system that Oracle Java JDK is available for use
sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.8.0_45/bin/javac" 1
c. Notify the system that Oracle Java Web start is available for use
sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.8.0_20/bin/javaws" 1
Inform your Linux system that Oracle Java JDK/JRE must be the default Java.
a. Set the java runtime environment for the system
sudo update-alternatives --set java /usr/local/java/jdk1.8.0_45/bin/java
b. Set the javac compiler for the system
sudo update-alternatives --set javac /usr/local/java/jdk1.8.0_45/bin/javac
c. Set Java Web start for the system
sudo update-alternatives --set javaws /usr/local/java/jdk1.8.0_20/bin/javaws
Reload your system wide PATH
source /etc/profile
Check the new version and you're done!
java -version
Just unpack the new Java version, for example into /opt. Then do
export JAVA_HOME=/opt/jdk1.8.0_45
export PATH=$JAVA_HOME/bin:$PATH
Put these exports into the startup files for your shell and you should be set. It is not necessary to uninstall the Java 7 installation.
On Centos/Redhat
First do : rpm -qa|grep jdk
And then : rpm -e <the version which you dont want>
I had java 7 installed on my ubuntu machine and wanted java 8. For that i followed the following steps
purge the older with sudo apt-get purge openjdk-\*
Add repository sudo add-apt-repository ppa:openjdk-r/ppa
Update the packages sudo apt-get update
Install java 8 with sudo apt-get install openjdk-8-jdk
To check list of java versions installed dosudo update-java-alternatives --list
Select default java for java sudo update-alternatives --config java
Select default java for javac sudo update-alternatives --config javac
check with java -version and javac -version to check if update version is installed
I referred following link Install OpenJDK8 on Unbuntu Trusty
Hope this helps!
I went to this article, the final option did it for me:
A final option for you to consider is yum remove libpcap, see how many packages it wants to remove (yum won't actually remove anything until you hit the Y button and press enter), since you may be able to remove these packages and use yum, if it turns out you couldn't after all, you can roll back with yum history undo command (I don't remember in what version of yum this was implemented in yum, so check first if this sub command is available to you). Also, make sure that you got your repositories pointing to the repos which has these files available.
After that I could remove my old jdk with:
sudo rpm -e java-1.8.0-openjdk-1.8.0.352.b08-2.el7_9
Note: This question was asked before Oracle made the OpenJDK the free version of the Oracle JDK, and the historic answers reflect that. As of 2022 you should not use Java 7 unless you must for projects which cannot run on OpenJDK 8.
To install java I have always used the classic way from the terminal.
I would like to install java manually.
I placed the folder of the JDK on the desk and I set environment variables (PATH, CLASSPATH and JAVA_HOME).
From the terminal, if I type java -version I get printed
foralobo#ubuntu-vincy:~$ java -version
java version "1.7.0_21"
Java(TM) SE Runtime Environment (build 1.7.0_21-b11)
Java HotSpot(TM) 64-Bit Server VM (build 23.21-b01, mixed mode)
But when I try to install eclipse or netbeans, the system warns by saying that there is no java installed on the machine.
What is missing to compleatare manual installation?
(Ubuntu 13.04)
This answer used to describe how to install Oracle Java 7. This no longer works since Oracle end-of-lifed Java 7 and put the binary downloads for versions with security patches behind a paywall. Also, OpenJDK has grown up and is a more viable alternative nowadays.
In Ubuntu 16.04 and higher, Java 7 is no longer available. Usually you're best off installing Java 8 (or 9) instead.
sudo apt-get install openjdk-8-jre
or, f you also want the compiler, get the jdk:
sudo apt-get install openjdk-8-jdk
In Trusty, the easiest way to install Java 7 currently is to install OpenJDK package:
sudo apt-get install openjdk-7-jre
or, for the jdk:
sudo apt-get install openjdk-7-jdk
If you are specifically looking for Java 7 on a version of Ubuntu that no longer supports it, see https://askubuntu.com/questions/761127/how-do-i-install-openjdk-7-on-ubuntu-16-04-or-higher .
sudo apt-get update
sudo apt-get install openjdk-7-jdk
and if you already have other JDK versions installed
sudo update-alternatives --config java
then select the Java 7 version.
In addition to flup's answer you might also want to run the following to set JAVA_HOME and PATH:
sudo apt-get install oracle-java7-set-default
More information at:
http://www.ubuntuupdates.org/package/webupd8_java/precise/main/base/oracle-java7-set-default
Note: According to comments this text was copied from a GIST without attribution.
Download java jdk<version>-linux-x64.tar.gz file from https://www.oracle.com/technetwork/java/javase/downloads/index.html.
Extract this file where you want. like: /home/java(Folder name created by user in home directory).
Now open terminal.
Set path JAVA_HOME=path of your jdk folder(open jdk folder then right click on any folder, go to properties then copy the path using select all)
and paste here.
Like: JAVA_HOME=/home/xxxx/java/JDK1.8.0_201
Let Ubuntu know where our JDK/JRE is located.
sudo update-alternatives --install /usr/bin/java java /home/xxxx/java/jdk1.8.0_201/bin/java 20000
sudo update-alternatives --install /usr/bin/javac javac /home/xxxx/java/jdk1.8.0_201/bin/javac 20000
sudo update-alternatives --install /usr/bin/javaws javaws /home/xxxx/java/jdk1.8.0_201/bin/javaws 20000
Tell Ubuntu that our installation i.e., jdk1.8.0_05 must be the default Java.
sudo update-alternatives --set java /home/xxxx/sipTest/jdk1.8.0_201/bin/java
sudo update-alternatives --set javac /home/xxxx/java/sipTest/jdk1.8.0_201/bin/javac
sudo update-alternatives --set javaws /home/xxxxx/sipTest/jdk1.8.0_201/bin/javaws
Now try:
$ sudo update-alternatives --config java
There are 3 choices for the alternative java (providing /usr/bin/java).
Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/lib/jvm/java-6-oracle1/bin/java 1047 auto mode
1 /usr/bin/gij-4.6 1046 manual mode
2 /usr/lib/jvm/java-6-oracle1/bin/java 1047 manual mode
3 /usr/lib/jvm/jdk1.7.0_75/bin/java 1 manual mode
Press enter to keep the current choice [*], or type selection number: 3
update-alternatives: using /usr/lib/jvm/jdk1.7.0_75/bin/java to provide /usr/bin/java (java) in manual mode
Repeat the above for:
sudo update-alternatives --config javac
sudo update-alternatives --config javaws
I think you should consider Java installation procedure carefully. Following is the detailed process which covers almost all possible failures.
Installing Java with apt-get is easy. First, update the package index:
sudo apt-get update
Then, check if Java is not already installed:
java -version
If it returns "The program java can be found in the following packages", Java hasn't been installed yet, so execute the following command:
sudo apt-get install default-jre
You are fine till now as I assume.
This will install the Java Runtime Environment (JRE). If you instead need the Java Development Kit (JDK), which is usually needed to compile Java applications (for example Apache Ant, Apache Maven, Eclipse and IntelliJ IDEA execute the following command:
sudo apt-get install default-jdk
That is everything that is needed to install Java.
Installing OpenJDK 7:
To install OpenJDK 7, execute the following command:
sudo apt-get install openjdk-7-jre
This will install the Java Runtime Environment (JRE). If you instead need the Java Development Kit (JDK), execute the following command:
sudo apt-get install openjdk-7-jdk
Installing Oracle JDK:
The Oracle JDK is the official JDK; however, it is no longer provided by Oracle as a default installation for Ubuntu.
You can still install it using apt-get. To install any version, first execute the following commands:
sudo apt-get install python-software-properties
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
Then, depending on the version you want to install, execute one of the following commands:
Oracle JDK 7:
sudo apt-get install oracle-java7-installer
Oracle JDK 8:
sudo apt-get install oracle-java8-installer
PPA method no longer works.
While Oracle Java 6 and 7 are not supported for quite a while, they were still available for download on Oracle's website until recently.
However, the binaries were removed about 10 days ago (?), so the Oracle Java (JDK) 6 and 7 installers available in the WebUpd8 Oracle Java PPA no longer work.
Oracle Java 6 and 7 are now only available for those with an Oracle Support account (which is not free), so I can't support this for the PPA packages.
Source : http://www.webupd8.org/2017/06/why-oracle-java-7-and-6-installers-no.html
Dated : June 2017
Oracle's download page says
Updates for Java SE 7 released after April 2015, and updates for Java SE 6 released after April 2013 are only available to Oracle Customers through My Oracle Support (requires support login).
Java SE Advanced offers users commercial features, access to critical bug fixes, security fixes, and general maintenance".
I had to download it from Oracle archives -
http://www.oracle.com/technetwork/java/javase/downloads/java-archive-downloads-javase7-521261.html
You need an account for this though.
Oracle Java 1.7.0 from .deb packages
wget https://raw.github.com/flexiondotorg/oab-java6/master/oab-java.sh
chmod +x oab-java.sh
sudo ./oab-java.sh -7
sudo apt-get update
sudo sudo apt-get install oracle-java7-jdk oracle-java7-fonts oracle-java7-source
sudo apt-get dist-upgrade
Workaround for 1.7.0_51
There is an Issue 123 currently in OAB and a pull request
Here is the patched vesion:
wget https://raw.github.com/ladios/oab-java6/master/oab-java.sh
chmod +x oab-java.sh
sudo ./oab-java.sh -7
sudo apt-get update
sudo sudo apt-get install oracle-java7-jdk oracle-java7-fonts oracle-java7-source
sudo apt-get dist-upgrade
flup's answer is the best but it did not work for me completely. I had to do the following as well to get it working:
export JAVA_HOME=/usr/lib/jvm/java-7-oracle/jre/
chmod 777 on the folder
./gradlew build - Building Hibernate
Oracle as well as modern versions of Ubuntu have moved to newer versions of Java. The default for Ubuntu 20.04 is OpenJDK 11 which is good enough for most purposes.
If you really need it for running legacy programs, OpenJDK 8 is also available for Ubuntu 20.04 from the official repositories.
If you really need exactly Java 7, the best bet as of 2020 is to download a Zulu distribution. The easiest to install if you have root privileges is the .DEB version, otherwise download the .ZIP one.
https://www.azul.com/downloads/?version=java-7-lts&os=ubuntu&architecture=x86-64-bit&package=jdk#download-openjdk
Open Applicaction -> Accessories -> Terminal
Type commandline as below...
sudo apt-get install openjdk-7-jdk
Type commandline as below...
apt-cache search jdk
(Note: openjdk-7-jdk is symbolically used here. You can choose the JDK version as per your requirement.)
For "JAVA_HOME" (Environment Variable) type command as shown below, in "Terminal" using your installation path...
export JAVA_HOME=/usr/lib/jvm/java-7-openjdk
(Note: "/usr/lib/jvm/java-7-openjdk" is symbolically used here just for demostration. You should use your path as per your installation.)
For "PATH" (Environment Variable) type command as shown below, in "Terminal" using your installation path...
export PATH=$PATH:/usr/lib/jvm/java-7-openjdk/bin
(Note: "/usr/lib/jvm/java-7-openjdk" is symbolically used here just for demostration. You should use your path as per your installation.)
Check for "open jdk" installation, just type command in "Terminal" as shown below
javac -version
I have installed java in my CentOS release 5.5 machine using the command yum install java. But I am unable to compile a class using javac.
Do I need to install any other package?
I have tried to locate the javac executable but i am unable to locate it.
/usr/bin/java is linked as follows:
/usr/bin/java -> /etc/alternatives/java
/etc/alternatives/java -> /usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/java
I have seen the following output by yum list installed |grep java:
java-1.6.0-openjdk.x86_64 1:1.6.0.0-1.16.b17.el5 installed
tzdata-java.x86_64 2011b-1.el5 installed
Worked for me with this command:
yum install java-devel
You installed the Java Runtime Environment (JRE) only, which does not provide javac. For javac, you have to install the OpenJDK Development Environment. You can install java-devel or java-11-devel, which both include javac.
By the way: you can find out which package provides javac with a yum search, e.g.
su -c 'yum provides javac'
on more recent releases of CentOS e.g. 6 the command changes to
su -c 'yum provides */javac'
Use the following sudo command:
sudo yum install java-1.6.0-openjdk-devel
I don't know exactly what yum install java will actually install. But to check for javac existence do:
> updatedb
> locate javac
preferably as root. If it's not there you've probably only installed the Java runtime (JRE) and not the Java Development Kit (JDK). You're best off getting this from the Oracle site: as the Linux repos may be slightly behind with latest versions and also they seem to only supply the open-jdk as opposed to the Oracle/Sun one, which I would prefer given the choice.
I use Fedora (currently 31)
Even with JDK's installed, I still need to specify JAVAC_HOME in the .bashrc, especially since I have 4 Java versions using sudo alternatives --configure java to switch between them.
To find java location of java selected in alternatives
readlink -f $(which java)
In my case:
/usr/java/jdk1.8.0_241-amd64/jre/bin/java
So I set following in .bashrc to:
export JAVA_HOME=/usr/java/jdk1.8.0_241-amd64/jre/bin/java
export JAVAC_HOME=/usr/java/jdk1.8.0_241-amd64/bin/javac
export PATH=$PATH:/usr/java/jdk1.8.0_241-amd64/jre/bin
export PATH=$PATH:/usr/java/jdk1.8.0_241-amd64/bin/
Now javac –version gives:
javac 1.8.0_241
This is useful for those who want to use Oracle's version. Just remember to change your .bashrc again if you make a change with java alternatives.
Is the javac executable in a directory that is part of your PATH?
I don't know the CentOS equivalent of the Windows path but if you cd to the java sdk directory and run ./javac does anything happen?
Install same version javac as your JRE
yum install java-devel
This worked for me:
sudo dnf install java-<version>-devel
You have installed the Java Runtime Environment(JRE) but it doesn't contain javac.
So on the terminal get access to the root user sudo -i and enter the password.
Type yum install java-devel, hence it will install packages of javac in fedora.
Linux Mint 19.3
I installed Java Oracle manually, like this:
$ sudo ln -s /usr/lib/jvm/java-1.8.0_211/bin/javac /usr/bin/javac
for java 8 use
sudo yum install java-1.8.0-openjdk-devel
Make sure you install JDK/JRE first.
follow these steps:
open terminal go to your root dictionary by typing
cd /
you will see Library folder
Now follow this path Library/Java/JVM/bin
Once you get into bin you can see the javac file
Now you need to get the path of this folder for that just write this command
pwd
get the path for your javac.