I’ve been thinking about setting up a Linux VM on my Mac for a little while now. I already have a Chrome VM. While I installed Java 7 on my Mac yesterday from Open JDK, I also wanted an “official” version. In case I come across anything odd, I want a way to know if it is from the Mac version being not quite ready or “the way things work.” Which gave me a reason/excuse to install the Linux VM. This blog entry is about how to get started.
WARNING: Java 7 is not yet production ready. See Java 7 Ships with Severe Bug. (it has to do with loops not functioning properly and affects Lucene and likely other things.)
For the Mac
Download and install
- Download Java 7 dmg file
- Install it
- Optional go to Java in system preferences to choose Java 7 as default. (I did not do this since it sounds experimental with known buts at this point.)
- Note the install location to reference is /Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home/bin.
Pointing to Java 7
Since Java 7 has reported stability problems, I didn’t want to set it in my PATH but only use it for selected command line invocations. To facilitate, I set up the following in my .bash_profile:
alias javac7='/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home/bin/javac' alias java7='/Library/Java/JavaVirtualMachines/1.7.0.jdk/Contents/Home/bin/java'
To validate the aliases are working:
Jeanne-Boyarskys-MacBook-Pro:~ nyjeanne$ javac7 -version javac 1.7.0-internal Jeanne-Boyarskys-MacBook-Pro:~ nyjeanne$ java7 -version openjdk version "1.7.0-internal" OpenJDK Runtime Environment (build 1.7.0-internal-b00) OpenJDK 64-Bit Server VM (build 21.0-b17, mixed mode)
Linux VM on VirtualBox
Download and install
- Download ubutntu iso file. It took a number of hours to download the iso file. (I let it run overnight.) While the download was less than 100MB, I downloaded Lion the night before (over 3GB) so my ISP may be throttling my connection speed now. That or a slow server. Note that you don’t need to create a USB stick or CD. Just the iso file is fine.
- Create a new VirtualBox VM and set CD drive to read from the downloaded iso file. Even those these instructions are for Windows, they were easy to follow on a Mac.
- Try to downloadthe .tar.gz file for Java 7. I got a page not found so I tried the .rpm file. This gave me errors when I installed and tried to run it.
javac -version gave:Error occurred during initialization of VM. java/lang/NoClassDefFoundError: java/lang/Object
- Deleted the bad install.
- Tried again to download the .tar.gz file for Java 7. This time the path was found.
Pointing to Java 7
Since my Linux machine is a VM specifically for trying Windows 7, I felt safe adding it to the beginning of my PATH in the .profile file.
A really simple Java program
A really simple program using a Java 7 feature to further test your setup.
<pre>import java.util.*;
public class JeanneTest {
public static void main(String... args) {
System.out.println("test");
Set<String> test = new HashSet<>();
}
}