code runner broken, missmatch between compiler & runner

[provide a description of the issue] I have no problem using the java & javac command in my terminal to compile and run the code, but when running inside VSCode it messes up, it throws error described under section Current Result

Environment

• Operating System: macOS Sierra, 10.12.6
• JDK version: java version “1.8.0_202”
• Visual Studio Code version: 1.31.1
• Java extension version: 0.4.0

Steps To Reproduce

1. install java8 with home brew
2. install the java extention pack in vscode
3. make a simple hello world
4. press the run code in vscode

[attach a sample project reproducing the error] Simple project running this code:

public class HelloWorld {
  public static void main(String[] args) {
    System.out.println("Hello, world");
  }
}

Current Result

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.UnsupportedClassVersionError: HelloWorld has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
	at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:495)

Expected Result

“Hello, world”

Additional Informations

Im pretty new to Java development, so i might also have messed something up. Here is a bit more information about my setup on the mac hopefully this can help to sole this issue:

➜  hello-world which java
/usr/bin/java
➜  hello-world ls -l `which java`
lrwxr-xr-x  1 root  wheel  74 24 Nov  2017 /usr/bin/java -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/java
➜  hello-world echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk1.8.0_202.jdk/Contents/Home
➜  hello-world java -version
java version "1.8.0_202"
Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
Java HotSpot(TM) 64-Bit Server VM (build 25.202-b08, mixed mode)
➜  hello-world javac -version
javac 1.8.0_202
➜  hello-world ls -l `which javac`
lrwxr-xr-x  1 root  wheel  75 24 Nov  2017 /usr/bin/javac -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/javac

[fbricon]

Fix is merged upstream. New 0.42.1 release is imminent. You might need to clean the workspace folders though, after reopening your folder.

[yaohaizh]

@testforstephen