Determining the Default Version of the JDK
If you have not yet installed Apple’s Java OS X 2012-006 update, then you are still using a version of Apple Java 6 that includes the plug-in and the Java Preferences app. See “Note for Users of OS X that Include Apple Java 6 Plug-in”.
There can be multiple JDKs installed on a system, as many as you wish.
When launching a Java application through the command line, the system uses the default JDK. It is possible for the version of the JRE to be different than the version of the JDK.
You can determine which version of the JDK is the default by typing
java -version in a Terminal window. If the installed version is 8u6, you will see a string that includes the text 1.8.0_06. For example:
% java -version java version "1.8.0_06-ea" Java(TM) SE Runtime Environment (build 1.8.0_06-ea-b13) Java HotSpot(TM) 64-Bit Server VM (build 23.2-b04, mixed mode)
To run a different version of Java, either specify the full path, or use the
% /usr/libexec/java_home -v 1.8.0_06 --exec javac -version
For more information, see the java_home(1) man page.
Uninstalling the JDK
To uninstall the JDK, you must have Administrator privileges and execute the remove command either as root or by using the sudo(8) tool.
/Library/Java/JavaVirtualMachines and remove the directory whose name matches the following format:Foot1
reset folder path in eclipse. [build path]
1. java.lang.UnsupportedClassVersionError 발생 원인
2. Java 의 버전 확인 방법
1) 이클립스의 Java 버전
프로젝트명에서 마우스 우클릭 -> Properties -> Java Compiler -> Compiler compliance level 확인