What's new in JDK 8(my short version)

JPL - Java Programming Language
1. Lambda expressions
2. Functional interfaces
3. method references
4. default methods
5. repeating annotations
6. type annotations
7. improved type inference

Collections
1. Stream API
2. Performance improvements for HashMaps with Key Collisions.

Compact Profiles - predefined subsets of Java SE platform to enable apps to be deployed on small devices.

JavaFX
1. Modena theme
2. Embedding swing content into JavaFX
3. New controls DatePicker and TreeTableView
4. javafx.print
5. New 3D Graphics features, like Shape3D, Material, LightBase
6. Improved WebView, including WebSockets, Web Workers and Web Fonts
7. Support for HiDPI displays
8. CSS Styleable classes made public
9. JavaFX available for ARM now

Tools
1. jjs command to invoke Nashorn engine
2. java command launches JavaFX apps
3. jdeps command line tool is provided for analyzing class files.
4. JMX (Java Management Extensions) provide remote access to diagnostic commands
Other Javac and Javadoc tool

Internationalization
1. New Calendar and Locale APIs (Instant, LocalDate, LocalTime, ZonedDateTime, Duration, Period etc.)
2. Unicode 6.2.0
3. Adoption of Unicode CLDR Data

Date-Time Package - a new set of packages that provide a comprehensive date-time model

Scripting
1. Rhino Javascript engine replaced by Nashorn

IO and NIO
1. Performance improvement for the java.lang.String(byte[], *) constructor and the java.lang.String.getBytes() method

java.lang and java.util
1. Parallel Array Sorting
2. Standard Encoding and Decoding Base64

Concurrency
1. New classes and improvements to java.util.concurrent

HotSpot
1. Removal of PermGen in favor of Metaspace. PermGen was continuously responsible for OutOfMemory.
PermGen contained class metadata, static content, String Pool (String interning).
PermGen was fixed in size and not eligible for GC.