-->What Version of Java Are You Using?
On a computer with multiple web browsers, be sure to check the Java version in every browser. I say this because multiple copies of Java can sometimes be installed with different browsers using different copies. Also, Java can be enabled in one browser and disabled in another.
Note: The portion of Java that runs programs is referred to as either the Java Run-time Environment (JRE) or the Java Virtual Machine (JVM).
This is my favorite - straight from the horse's mouth (so to speak). The Java Run-time Environment is aware of its version and the company that authored it. So I wrote a very simple applet (the source code is on the About page) that gets this information from the JRE and displays it in a pink rectangle.
If Java is working, you will see a pink rectangle above with one line of text that says something like:
Java Version 1.8.0_25 from Oracle Corporation or
Java Version 1.7.0_67 from Oracle Corporation or
Java Version 1.6.0_45 from Sun Microsystems Inc. or
Java Version 1.6.0_33 from Apple Inc.
In part this is because the applet is unsigned. In the Bizarro world of Oracle, unsigned applets are treated as more dangerous than signed applets. This is backwards for two reasons. First, unsigned applets run in a restricted Java sandbox whereas signed applets are given unrestricted access to the system. Yes, the sandbox has been buggy and broken, but some security is better than none. Second, it shows a faith in the Certificate Authority system that is unwarranted.
Java on Mac Computers
The rest of this topic is a bit dated, so it has been suppressed by default.
At times Java on OS X was complicated as Java 6 came from Apple and Java 7 came from Oracle.
For many years this page had eight other methods of determining the installed version of Java.
But the page got really big, so they are no longer shown by default. But, they are still available:
Website created and maintained by Michael Horowitz mh _at_ javatester.org
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