What exactly is added in Java language levels 7.0 and 8.0?

I just noticed the option to select Java Language Levels 7.0 and 8.0 in IntelliJ (under Project Settings).

Where can I find a concise desc开发者_开发技巧ription of what these enable? Level 7.0 is stated to enable "Dimonds" (what is this?), Strings in switches (cool!), and "etc..." ?

Level 8.0 has "Type Annotations", which I don't know of.

Do I have to use the appropriate JDK to setup a higher level? IntelliJ doesn't seem to mind me setting Language Level 7.0 and JDK 1.6.

some info here - http://blogs.jetbrains.com/idea/tag/java7/

If you are up to some reading, here are links for the official JSRs (Java Specification Requests).

JSR 336 - Java SE 7

JSR 337 - Java SE 8

They contain links to further JSRs that are incorporated in them.

Project Coin has some good features:

Features in Project Coin