This document summarizes new features and enhancements in Java SE 7, including allowing strings in switch statements, binary and underscored numeric literals, try-with-resources for automatic resource management, and the diamond operator for simplifying generic object creation. It also briefly mentions features like multiple exception handling in a catch clause, the Path API for type-safe file paths, directory streaming and watching capabilities in NIO.2, and the future of Java focusing on productivity, performance, and modularization.

1. Java SE 7 New Features &
Enhancements
Fu Cheng @alexcheng1982

2. Author of Understanding the Java 7 Author of technical articles on

3. Agenda
• Usefull tips
– Language
– IO
• No deep dive topics

4. Why Java Platform

5. Why Java
http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html

6. Why Java
• Easy to learn
– Simple
• Easy to use
– Strong community
– All kinds of third-party libraries
• HARD to do things WRONG
– Static typed
– Rigid syntax

7. Why Java 7
• 5 years from Java SE 6 to Java SE 7
• New features
– JVM level
– Language level
– API
• Enhancements
– Performance
– Management
– Documentation

8. String in Switch
• “switch” statement
• Prior to Java 7
– Can only use data type compatible with integer in
“switch”
• Java 7
– String type is allowed
• Under the hood
– Switch by string hash code

9. Sample

10. Numeric Literals
• Java only supports literals of primitive types
– List & map literals – Java SE 8 (maybe)
• Binary literals
– Prefixed with 0b or 0B
• 0b001001
• Underscores in literals
– Align for readability
• 5_6.3_4

11. Exception Handling
• Multiple exception types in one catch clause

12. try-with-resources
• Use try clause to manage resources
– “finally” not required
– Resource released automatically
• Make you own resource manageable by try
clause
– Implement java.lang.AutoCloseable
– “close”method invoked automatically

13. Sample
File copy example

14. Diamond Operator
• Use diamond (<>) operator to simply generic
objects creation
Old way
New way

15. Path
• java.nio.file.Path
– New abstraction for file path
– Say goodbye to using string for file path
– Type safe

16. Directory Stream
• java.nio.file.DirectoryStream
• List files in directory
• Provide better performance than “File.list” and “File.listFiles”
• Extend from Iterable

17. Directory Watcher
• Get notified when files changed in a directory
– Entry created, modified or deleted

18. Those Not Included
• JSR 292 – “invokedynamic” instruction
• Concurrency utilities
– Fork/join framework
– Phaser
• I18N
– Unicode 6.0
– IETF BCP 47
• NIO.2
– Zip/jar file system
– Async I/O
• JDBC 4.1

19. Future of Java
• Productivity
– Enhanced for loop (Java SE 5)
– try-with-resources (Java SE 7)
– Diamond operator (Java SE 7)
– Lambda expression (Java SE 8)
• Performance
– Fork/join framework (Java SE 7)
– Collection framework enhancements (Java SE 8)
• Modularization
– Project Jigsaw (Java SE 8)