Please try the following steps:
Rename the default workspace"Adobe Flash Builder 4.7"( on Mac it's located at /Users/USER_NAME/Documents/Adobe Flash Builder 4.7) and try launching Flash Builder.Even if this doesn't work. Please un-install Flash Builder and use the cleaner tool(from this location http://www.adobe.com/support/contact/cscleanertool.html ) to clean and re-install Flash Builder.
Please let me know if this works.
That didn't work.
However I did figure out that the problem is that the JVM 1.8 doesn't support the Java Native Interface quite right. JVM 1.8 was installed as part of JDK 8 when this machine was set up by IT. Uninstalling the JDK, then installing JDK 7 got things going.
For anyone who runs into this problem. I am running OSX El Captain you want to remove Java 1.8.
If from the terminal you run:
and you have something greater than 1.7 Flash builder doesn't run
I happened to have 1.7 on my machine from before so simply navigating to:
sudo rm -rf jdk1.8.0_51.jdk/
worked for me
This page helped