I want to install a specific JDK (the latest for example). For this, I went to the JDK download homepage: http://java.sun.com/javase/downloads/index.jsp. I looked for a Mac version, but I'm a bit surprised to only see downloadable versions for Linux, Windows and Solaris...
Here's the message for Mac:
"Apple Computer supplies their own version of Java. Use the Software Update feature (available on the Apple menu) to check that you have the most up-to-date version of Java for your Mac."
OK BUT... when I update Java with Mac I have a JRE and not a JDK...
I don't understand why a JDK version doesn't exist that is easily downloadable/installable (like a jar to unzip?) for Mac...
In a comment under @Thilo's answer, @mobibob asked how to set JAVA_HOME in your .bash_profile on a Mac. Answer:
export JAVA_HOME=`/usr/libexec/java_home`
This will dynamically assign to JAVA_HOME the location of the first JDK listed in the "General" tab of "Java Preferences" utility.
See Apple Technical Q&A 1170: https://developer.apple.com/library/content/qa/qa1170/_index.html
EDIT:
If you prefer parentheses to backticks for command substitution, this also works:
export JAVA_HOME=$(/usr/libexec/java_home)