How to run simple java app on amazon ec2?

Question

I have access to amazon cloud service ec2, linux instance. I created vi first.java file with this content:

class first {
    public static void main(String[] args) {
        System.out.println("abc");
    }
}

I want to compile the file using:

[root@ip-21-24-273-243 ec2-user]# javac first.java 
bash: javac: command not found

Command not found? I do:

[root@ip-21-24-273-243 ec2-user]# java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.9) (amazon-57.1.11.9.52.amzn1-x86_64)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

So java is installed. How can I run a simple app?

[root@ip-21-24-273-243 ec2-user]# yum install java
Loaded plugins: priorities, security, update-motd, upgrade-helper
amzn-main                                                                                                                      | 2.1 kB     00:00     
amzn-updates                                                                                                                   | 2.3 kB     00:00     
Setting up Install Process
Package 1:java-1.6.0-openjdk-1.6.0.0-57.1.11.9.52.amzn1.x86_64 already installed and latest version
Nothing to do

Answer 1

你需要安装java-1.6.0-openjdk-devel:

yum install java-devel

Answer 2

As already mentioned, to compile a Java program you need JDK. Here you may find some useful information on how to install JDK on a Fedora AMI: Compiling and running Java app

However, you should notice that you don't need to compile on your ec2 instance. You can compile your Java program on your home desktop/laptop computer and transfer compiled .class (packed in a .jar) files to the instance, and run them there - the already installed JRE should be enough to run the program. That is a preferable approach, cause you can comfortably use Eclipse for development. Develop, test on your local machine, deploy on ec2.

Answer 3

There's a few steps to do:

1. Make sure you have a Java compiler installed. You can find this out by entering $javac into your console and seeing what comes up. If it's not installed, follow the previously mentioned instructions to $yum install java-devel
2. Create your script ( first.java )
3. Compile it using $javac first.java
4. You will now have first.java and first.class ... execute it by executing $java first

Answer 4

"[Java] Runtime Environment" or "JRE" for short doesn't include the developer tools, one of them being the Java Compiler. You need to install Java Development Kit or "JDK" for short. The exact mechanism depends on which AMI you used to build your instance.

Answer 5

In order to create and run a basic java program on Amazon EC2 , you would require to do following:

1. When you login to EC2 instance, check whether JDK is installed or not, fire javac -version for it. If you do not have JDK installed you would see something like this:
2. Install JDK, fire sudo rpm -i jdk-8u11-linux-x64.rpm
3. Having java installed, you can create a file file.java using any editor.
4. Edit the file and save.
5. Compile java File, javac file.java
6. Run it, java file