After downloading Eclipse (Luna 4.4.2) on Max OS X 10.10.3 Yosemite it failed to start-up. It gave the highly misleading error message To open “eclipse” you need to install the legacy Java SE 6 runtime.
Installing Java 6 isn’t a good idea. It’s out of support and now has a number of serious security issues. Common sense says there has to be a better solution.
Try going to the OS X Command line and enter the command java -version
In my case then displayed the message, To use the “java” command-line tool you need to install a JDK.
Note that it’s asking you to install a JDK. I knew I had the latest version of Java runtime (JRE) installed so had expected the Java -version command to display Java 8. Clicking on More info will take you through to the Oracle Java download site.
From here download the Mac OS X 64 bit JDK and then when the download has completed click on the dmg file in the download loads directory and follow the install instructions.
Once complete try the Java -version command again from the command line to prove the install has been successful. In my case this came back with:
java version “1.8.0_45”
Java(TM) SE Runtime Environment (build 1.8.0_45-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.45-b02, mixed mode)
Now clicking on the Eclipse icon will successfully launch Eclipse.
To prove it here’s the Eclipse About box to show Eclipse Luna 4.4.2 successfully running on OS X 10.10.3.
Update: June 19th 2016:
A recent update broke the above solution. I hadn’t used Eclipse on the affected Mac for a few weeks so I’m not sure if it was broken by a Java update, an OSX update or even an Eclipse update. Anyway the solution was a simple extension of the above steps.
Find your eclipse.app and CTRL right click on it, you will then see a ‘Show Package Contents’ option
Now navigate to the eclipse.ini shown below:
Now edit eclipse.ini and look for the highlighted line:
Shown above is the correct setting for my Mac that now works. I’ve seen this incorrectly set to either the wrong location or even to a specific Java patch level. If you’ve got a different location under -vm make a note or backup and then try changing it to this more standard value.
If you have any problems or follow-up questions do please leave a comment below.