<tl;dr> To fix the Eclipse “No Java virtual machine was found” error, simply edit the eclipse-inst.ini file and add the -vm flag, which points it to the java utility in the JDK bin directory: ...

Don't let high Java CPU usage problems on Windows or Linux distract you from the underlying performance problem you're trying to troubleshoot. There are many ways to fix 100% Java CPU utilization ...

To clear the Java cache, open the Java control panel, which you can find in the Windows Control Panel or in System Preferences on a Mac.