I got this error and found that my PATH variable (on Windows) was probably changed. First in my PATH was this entry:
C:\ProgramData\Oracle\Java\javapath
...and Eclipse ran "C:\ProgramData\Oracle\Java\javapath\javaw"
- which gave the error. I suspect that this is something that came along with an installation of Java 8.
I have several Java versions installed (6,7 and 8), so I removed that entry from the PATH and tried to restart Eclipse again, which worked fine.
If it's doesn't work for you, you'll need to upgrade your JDK (to the Java versions - 8 in this case).