Failed to open or import Maven project in IntelliJ IDEA

I'm using IntelliJ IDEA 14 on Mac OSX Lion and I hadn't had any problems with opening or importing Maven projects before I updated Java from 1.6 to 1.8. The IDE started successfully but every time I opened or imported an existing Maven project, a popup appeared to display the progress of opening or importing process for a short time but after that nothing happened. Then, I opened the Console application and I see the log message below:

3/31/15 1:05:18.637 AM [0x0-0x8d38d3].com.jetbrains.intellij.ce:   Referenced from: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java
3/31/15 1:05:18.637 AM [0x0-0x8d38d3].com.jetbrains.intellij.ce:   Reason: image not found

It means that IDEA was still using JDK 1.6 and it no longer existed on my machine after the update. I solved the problem by telling it to use the JDK 1.8 instead when starting and building projects. To do it, I did as followings:

1). Open the IDEA's configuration file:

open -e /Applications/IntelliJ\ IDEA\ 14\ CE.app/Contents/Info.plist 

2). Update the following key

<key>JVMVersion</key>
<string>1.7+</string>

I have both JDK 1.7 and 1.8 on my machine.

3). Restart the IDE

Reference

https://devnet.jetbrains.com/docs/DOC-197