You have several issues here.

1. you don't have Java added to your system path and environment. $JAVA_HOME is likely not set and $JAVA_HOME/bin not added to the path.
2. Java 11 does not come with tools.jar as the entire Java packaging system was changed in Java 9 or 10. Install JDK 8 instead.
3. You're installing a JRE where you need a JDK.

Download the latest JDK 8 for your platform from http://java.oracle.com and follow the installation instructions.

Android SDK setup

-Method 1 :

Update Ubuntu

You should always update your system first before you do anything else. Run the following commands:

 sudo apt-get update && apt-get upgrade 

And install the required package if you don’t have it already installed:

sudo apt-get install software-properties-common 

Install Java

using ubuntu terminal :

sudo dpkg --add-architecture i386 sudo apt-get install libbz2-1.0:i386 sudo apt-get install libc6:i386 libncurses5:i386 libstdc++6:i386 lib32z1 sudo apt-get install openjdk-8-jdk openjdk-8-jre 

```

Add JAVA_HOME to path via ~/.bashrc

using ubuntu terminal :

export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64 

Check what Java version you’re using:

java -version 

The output should be something like:

Java(TM) SE Runtime Environment (build 8.0.4+11) Java HotSpot(TM) 64-Bit Server VM (build 8.0.4+11, mixed mode) 

-Method 2 :

Install Java using the Oracle JDK:

Step 1: Update Ubuntu

sudo apt-get update && apt-get upgrade 

And install the required package if you don’t have it already installed:

sudo apt-get install software-properties-common 

Step 2: Add the Java repository

sudo add-apt-repository ppa:webupd8team/java 

And then update your package list again:

sudo apt-get update 

Step 3: Install Java

Currently, Java 9 is considered stable, though you’ll find many other outdated tutorials saying 9 is still a “developer/beta/preview” release, it’s actually stable. So you should install Java 9. Java 10 should be released soon (March 2018).

So to install the JDK 9th (stable) version, run the following command:

sudo apt-get install oracle-java9-installer 

If, for any reason, you need the 8th version, run the following command:

sudo apt-get install oracle-java8-installer 

And that’s it. You can now configure your Java

Configure your Java

Set the JAVA_HOME variable

You’ll most likely need to set the JAVA_HOME variable so other applications can find the location of your Java installation. To find the Java installation path, run the previous command again:

update-alternatives --config java 

And copy the installation path – second column – under “Path”.

Next, open the file “/etc/environment” with a text editor

nano /etc/environment 

And add the following line at the end of the file:

JAVA_HOME="/your/java/installation-path" 

Of course, make sure you update the path with the one you previously copied, example:

JAVA_HOME="/usr/lib/jvm/java-9-oracle" 

Save the file and then reload it:

source /etc/environment 

To test if everything’s done right, you can check your JAVA_HOME variable using:

echo $JAVA_HOME 

And the output should be your Java installation path.

Install Android Studio

Download ZIP archive for Linux from: https://developer.android.com/studio/install.html 1. move the .zip to /opt 2. extract it 3. chown the folder to your name 4. chmod 777 studio.sh and run it for the installer

Now the android sdk is installed to ~/Android/Sdk It's preferred to add ~/Android/Sdk folders to your path:

using ubuntu terminal :

export PATH=${PATH}:~/Android/Sdk/tools export PATH=${PATH}:~/Android/Sdk/platform-tools 

```

Run android, install the images (atom, etc) and then navigate to Tools -> Manage AVDs and create a new image Make sure to install the android-23 version and confirm it exists in ~/Android/Sdk/platforms/

FYI: Worked like a charm. Bt I'm using Ubuntu 17.10

hope this helps! by QAL.

Thank you loads for your replies. I managed to install Java in the end by simply using --reinstall.

However, my original problem remains. I am trying to build LK bootloader images for the Dragonboard 410c from 96boards. When I go to run make I get the error

Your version is: openjdk version "1.8.0_171" OpenJDK Runtime Environment (build 1.8.0_171-8u171-b11-0ubuntu0.18.04.1-b11) OpenJDK 64-Bit Server VM (build 25.171-b11, mixed mode). 

The required version is: "1.7.x"

I know in older versions of Ubuntu openjdk wasn't supported but it is now and I can successful build the AOSP for Dragonboard 410c available from the 96boards website.

So why would I get the error for one when the other builds?

Many many thanks!!