How to check which version of JRE the eclipse is using ?
This section :
Window--->Preferences--->Java
shows by the name of JDK :
Open the About Eclipse dialog (Help -> About Eclipse on Windows, Eclipse -> About Eclipse on OS X)
Click "Installation Details", choose the Configuration tab, and scroll down to the "java.home" entry. The value is the path name to the JVM used.
To see which Java Eclipse itself is using go to Help > About Eclipse click Installation Details and look at the Configuration tab.
When you run Java programs from Eclipse you can select which Java is used. Preferences > Installed JREs lists the JREs (and JDKs) that Eclipse knows about. The Run Configuration for the program shows which Java is used to run the program.
Please see the following figure.
Goto Window->Preference->Installed JRES
or Goto Project , right click Preference -> Jva Build Path -> libraries
来源：https://stackoverflow.com/questions/22385457/how-to-check-for-the-jre-version-in-eclipse