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Cordova picking up wrong version of java

I am trying to run
cordova build android
It gives the following error
Checking Java JDK and Android SDK versions
ANDROID_SDK_ROOT=/home/bappaditya/Softwares/android-studio (recommended setting)
ANDROID_HOME=/home/bappaditya/Softwares/android-studio (DEPRECATED)
Requirements check failed for JDK 8 ('1.8.*')! Detected version: 12.0.2
Check your ANDROID_SDK_ROOT / JAVA_HOME / PATH environment variables.
I can see that it has picked up ANDROID_HOME and ANDROID_SDK_ROOT but not the correct version of java
My current environment
>java -version
openjdk version "1.8.0_275"
OpenJDK Runtime Environment (build 1.8.0_275-8u275-b01-0ubuntu1~20.04-b01)
OpenJDK 64-Bit Server VM (build 25.275-b01, mixed mode)
>echo $JAVA_HOME
/usr/lib/jvm/java-8-openjdk-amd64
>echo $PATH
/home/bappaditya/.cargo/bin:/opt/gradle/gradle-5.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/home/bappaditya/bin:/usr/lib/jvm/java-8-openjdk-amd64/bin
As you can see the JAVA 8 is installed and set as default. Why cordova complaining about java version?

It seems cordova uses javac to identify the version and not java.
So the command that really shows the version cordova gets when looking for Java is:
javac -version
In my case, even though I had identical versions to what you have in your environment, it turned out my javac was pointing to a newly updated Java (from Ubuntu updates)
To fix it, I used the update-alternatives command and set javac back to my 1.8.0 version as follow:
sudo update-alternatives --config javac

JDK Version inconsistent

My os is Ubuntu 16.04 LTS.
$ cat /etc/profile # part content of this file
JAVA_HOME=/usr/local/java/jdk1.8.0_101
JRE_HOME=$JAVA_HOME/jre
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME
export JRE_HOME
export PATH
$ echo $JAVA_HOME
/usr/local/java/jdk1.8.0_101
$ java -version
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)
$ ls /usr/local/java/
jdk1.7.0_79/ jdk1.8.0_101/
Why is my java version still jdk7?

Ubuntu has ability to work with multiple java versions. In your case, it just means that it has both JDK 7 and JDK 8 installed in your system but is using JDK 7.
To switch from one java version to another, you can use sudo update-alternatives --config java. This will list all JDKs installed in your system, just enter the number corresponding to JDK 8 and it should switch to JDK 8.

Run which java in your command shell. That will tell you where the java command you are running is coming from.
I suspect that is will tell you "/usr/bin/java" ... because this:
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
puts your new bin directories onto the end of the search path, not the beginning.
However, the better way to do this would be to use alternatives as suggested by another Answer. (With a custom installation in "/usr/local" this will require some fiddling around to get "alternatives" to understand the alternative.)

Need help installing Java 8 on Mac OS X

I am trying to upgrade to: Java 8 Update 66, from Java 6, on my Mac running Mac OS X 10.10.5. I downloaded the Java Update .dmg file: re-8u66-macosx-x64.dmg. When I run the installer I get the message it installed properly. When I confirmed the install via the FireFox Browser at this URL:
https://java.com/en/download/installed.jsp
It reports:
Congratulations!
You have the recommended Java installed (Version 8 Update 66).
However, If I open a terminal window and enter: java -version
It reports:
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-466.1, mixed mode)
Can someone please explain what is going on here? Do I need to update a link somewhere?
Thanks.

Please check your PATH variable, and make sure that the java directories in the path match the directories in your computer. It should be the bin folder of the JAVA_HOME environment directory. Also check that JAVA_HOME environment variable is set to the jdk folder of your java installation.

There's two option based on my experience to fix this issue, fisrt uninstalled the java on your computer and reinstalled using the latest version.
Second, run a different version of Java, either specify the full path, or use the java_home tool:
List your installed java version:
$ /usr/libexec/java_home -V
In this case you are using java 8 so you can run command
$ /usr/libexec/java_home -v 1.8 --exec javac -version
If you want to make easy to switch your java version you can create alias in ~/.bashrc
alias java6="export JAVA_HOME=$(/usr/libexec/java_home -v 1.6);echo 'using Java 6'"
alias java8="export JAVA_HOME=$(/usr/libexec/java_home -v 1.8);echo 'using Java 8'"
Hope it help

Why doesn't netbeans 7.3 see that I've installed Java 1.7.0_21?

I've recently installed netbeans 7.3 on my Mac (Lion 10.7.5, up-to-date).
At the command line, I would get:
[129]$java -version
java version "1.6.0_45"
Java(TM) SE Runtime Environment (build 1.6.0_45-b06-451-11M4406)
Java HotSpot(TM) 64-Bit Server VM (build 20.45-b01-451, mixed mode)
Today I went to the netbeans plugin window and found 18 updates to install. When I attempted to do this, I received a message that some of them require > Java 1.7, and I only have 1.6 (as indicated above). So I dutifully ran out to java.com and downloaded Java 1.7 Update 21 successfully.
When I run a Java version checker in various browsers I see a report that Java 1.7.0_21 is the installed version. In addition, the Mac's Java Control Panel also indicates that 1.7.0_21-b12 is the current version.
However, upon restarting netbeans, it still has the same complaint that Java 1.6 is in use. I've rebooted the machine and get the same result. And, the result of 'java -version' at the command line also still shows the same result as above (1.6.0_45).
And, finally, even if I try something like:
/usr/libexec/java_home -v 1.7.0_21 --exec java -version
I get:
Unable to find any JVMs matching version "1.7.0_21"
I'm baffled. Does anybody have any advice on this?
Thanks.
Doug

netbeans will be using it's own version of the the JDK try this
where-can-i-set-the-jre-jdk-which-is-used-to-run-netbeans-besides-the-command-line

Which JRE am I using?

There are two varieties of JRE available. Java VM: IBM vs. Sun.
Is there a way to know which JRE I am using through JavaScript or some Java issued command.

The following command will tell you a lot of information about your java version, including the vendor:
java -XshowSettings:properties -version
It works on Windows, Mac, and Linux.

System.out.println(System.getProperty("java.vendor"));
System.out.println(System.getProperty("java.vendor.url"));
System.out.println(System.getProperty("java.version"));
Sun Microsystems Inc.
http://java.sun.com/
1.6.0_11
http://docs.oracle.com/javase/tutorial/essential/environment/sysprop.html

Open up your:
command prompt if you're using Windows
terminal if you're using mac or Linux
Type in:
java -version // This will check your JRE version
javac -version // This will check your Java compiler version if you installed the JDK
Grab a cup of coffee and you're done! You don't need to add the .exe to the java -version if everything is installed correctly.

In Linux:
java -version
In Windows:
java.exe -version
If you need more info about the JVM you can call the executable with the parameter -XshowSettings:properties. It will show a lot of System Properties. These properties can also be accessed by means of the static method System.getProperty(String) in a Java class. As example this is an excerpt of some of the properties that can be obtained:
$ java -XshowSettings:properties -version
[...]
java.specification.version = 1.7
java.vendor = Oracle Corporation
java.vendor.url = http://java.oracle.com/
java.vendor.url.bug = http://bugreport.sun.com/bugreport/
java.version = 1.7.0_95
[...]
So if you need to access any of these properties from Java code you can use:
System.getProperty("java.specification.version");
System.getProperty("java.vendor");
System.getProperty("java.vendor.url");
System.getProperty("java.version");
Take into account that sometimes the vendor is not exposed as clear as Oracle or IBM. For example,
$ java version
"1.6.0_22" Java(TM) SE Runtime Environment (build 1.6.0_22-b04) Java HotSpot(TM) Client VM (build 17.1-b03, mixed mode, sharing)
HotSpot is what Oracle calls their implementation of the JVM. Check this list if the vendor does not seem to be shown with -version.

The Java system property System.getProperty(...) to consult is "java.runtime.name". This will distinguish between "OpenJDK Runtime Environment" and "Java(TM) SE Runtime Environment". They both have the same vendor - "Oracle Corporation".
This property is also included in the output for java -version.

Open a command prompt:
Version: java -version
Location: where java (in Windows)
which java (in Unix, Linux, and Mac)
To set Java home in Windows:
Right click on My computer → Properties → Advanced system settings → Environment Variable → System Variable → New.
Give the name as JAVA_HOME and the value as (e.g.) c:\programfiles\jdk
Select Path and click Edit, and keep it in the beginning as:
%JAVA_HOME%\bin;...remaining settings goes here

Git Bash + Windows 10 + Software that came bundled with its own JRE copy:
Do a "Git Bash Here" in the jre/bin folder of the software you installed.
Then use "./java.exe -version" instead of "java -version" to get the
information on the software's copy rather than the copy referenced by your PATH environment variable.
Get the version of the software installation: ./java.exe -version
JMIM#DESKTOP-JUDCNDL MINGW64 /c/DEV/PROG/EYE_DB/INST/jre/bin
$ ./java.exe -version
java version "1.8.0_131"
Java(TM) SE Runtime Environment (build 1.8.0_131-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.131-b11, mixed mode)
Get the version in your PATH variable: java -version
JMIM#DESKTOP-JUDCNDL MINGW64 /c/DEV/PROG/EYE_DB/INST/jre/bin
$ java -version
java version "10" 2018-03-20
Java(TM) SE Runtime Environment 18.3 (build 10+46)
Java HotSpot(TM) 64-Bit Server VM 18.3 (build 10+46, mixed mode)
As for addressing the original question and getting vendor information:
./java.exe -XshowSettings:properties -version ## Software's copy
java -XshowSettings:properties -version ## Copy in PATH

I had a problem where my Java applications quit work with no discernible evidence that I could find. It turned out my system started using the 64-bit version rather than the 32-bit version was needed (Windows Server 2012). In Windows, the command:
Javaw -version
just brought me back to the command prompt without any information. It wasn't until I tried
Javaw -Version 2>x.txt
type x.txt
that it gave me what was being executed was the 64-bit version. It boiled down to my PATH environment variable finding the 64-bit version first.

As you are expecting it to know using the Javascript, I believe you want to know the JRE versioned being used in your browser. Hence you can include Java version tester applet which can exactly tell you the version of the current browser.
import java.applet.*;
import java.awt.*;
public class JavaVersionDisplayApplet extends Applet
{
private Label m_labVersionVendor;
public JavaVersionDisplayApplet() // Constructor
{
Color colFrameBackground = Color.pink;
this.setBackground(colFrameBackground);
m_labVersionVendor = new Label (" Java Version: " +
System.getProperty("java.version") +
" from "+System.getProperty("java.vendor"));
this.add(m_labVersionVendor);
}
}

To check actually runned Java version you can use java.lang.Runtime API available since Java 10.
Runtime.Version version = Runtime.version();
int javaVersion = version.feature();
// returns 17 for Java 17