Zz Java7 新特性集合（官方英文版）

Java Platform Standard Edition 7 Documentation

        Oracle has two products that implement Java Platform Standard Edition (Java SE) 7: Java SE Development Kit (JDK) 7 and Java SE Runtime Environment (JRE) 7.

        JDK 7 is a superset of JRE 7, and contains everything that is in JRE 7, plus tools such as the compilers and debuggers necessary for developing applets and applications. JRE 7 provides the libraries, the Java Virtual Machine (JVM), and other components to run applets and applications written in the Java programming language.

        The following conceptual diagram illustrates Java component technologies:

 

  

     

What's New in Documentation

Documentation is regularly updated to provide developers with in-depth information about new features in the Java platform. Some recent updates include：

 

1.Swing

The following topics are covered:

JLayerClass

NimbusLook & Feel

Heavyweightand Lightweight Components

Shapedand Translucent Windows

Hue-Saturation-Luminance(HSL) Color Selection in JColorChooser Class

 

  Image 1   NimbusLook & Feel

   Image 2 TranslucentWindow

    Image 3 GradientWindow

 Image 4 ShapedWindow

 

2. Networking Enhancements in Java SE 7

The URLClassLoader.closemethod has been added. This method effectively eliminates the problem of how tosupport updated implementations of the classes and resources loaded from aparticular codebase, and in particular from JAR files. See Closing a URLClassLoader for moreinformation.

The SocketsDirect Protocol (SDP) provides access to high performance network connections;see Understanding the Sockets Direct Protocolin The Java Tutorial.

3.CollectionsFramework Enhancements in Java SE 7

The interface TransferQueue has been added. It is a refinement of the BlockingQueue interface in which producers can wait forconsumers to receive elements. One implementation of the new interface is alsoincluded in this release, LinkedTransferQueue.

4. Client JRE Capabilities - Quick Reference

The window ofa dragged applet can be decorated with a default or custom title; see Requesting and Customizing Applet Decoration inDraggable Applets.

The followingenhancements have been made to the syntax of JNLP files; see JNLP File Syntax:

The os attribute in the information and resources elementscan now contain specific versions of Windows, such as Windows Vista or Windows7.

Applicationscan use the install attribute in the shortcut element to specify their their desireto be installed. Installed applications are not removed when the Java Web Startcache is cleared, but can be explicitly removed using the Java Control Panel.

Java Web Startapplications can be deployed without specifying the codebase attribute; see Deploying Without Codebase

A JNLP filecan be embedded into an HTML page; see Embedding JNLP File in Applet Tag.

You can checkthe status variable of the applet while it is loading to determine if theapplet is ready to handle requests from JavaScript code; see Handling Initialization Status With Event Handlers.

You now havecontrol of the window decoration style and title of an applet launched from ashortcut or dragged out of the browser; see Requesting and Customizing Applet Decorationin Developing Draggable Applets. 

5. Java XML Technology Enhancements

This release contains Java API for XMLProcessing (JAXP) 1.4.5, supports Java Architecture for XML Binding(JAXB) 2.2.3, and supports Java API for XML Web Services (JAX-WS)2.2.4.

6. java.lang Package

Potentialdeadlocks were eliminated for multithreaded, non-hierarchically delegatingcustom class loaders; see Multithreaded Custom Class Loaders in Java SE 7.

7.Java Virtual Machine

Java Virtual Machine Support forNon-Java Languages: Java SE 7introduces a new JVM instruction that simplifies the implementation ofdynamically typed programming languages on the JVM.

Garbage-First Collector is a server-style garbage collector that replacesthe Concurrent Mark-Sweep Collector (CMS).

Java HotSpot Virtual MachinePerformance Enhancements

8. Java I/O

The java.nio.file package and its related package, java.nio.file.attribute, provide comprehensive support forfile I/O and for accessing the file system; see File I/O (featuring NIO.2). NIO stands for non-blocking I/O.

The directory <Java home>/sample/nio/chatserver/ contains samplesthat demonstrate the new APIs contained in the java.nio.file package.

The directory <Java home>/demo/nio/zipfs/ contains samples thatdemonstrate the NIO.2 NFS (Network File System) file system.

9. Security

A new nativeprovider has been added that provides several ECC-based algorithms(ECDSA/ECDH); see Sun PKCS#11 Provider's Supported Algorithmsin Java PKCS#11 Reference Guide.

Weakcryptographic algorithms can now be disabled; see Appendix D: Disabling Cryptographic Algorithmsin Java PKI Programmer's Guide andDisabled Cryptographic Algorithms in Java Secure Socket Extension (JSSE) Reference Guide.

Variousenhancements related to SSL/TLS have been added to Java Secure Socket Extension.

10. Concurrency

Thefork/join framework, which is based on the ForkJoinPoolclass, is an implementation of the Executorinterface. It is designed to efficiently run a large number of tasks using apool of worker threads. A work-stealing technique is used to keep all theworker threads busy, to take full advantage of multiple processors. SeeFork/Joinin The Java Tutorials.

Thedirectory <Java home>/sample/forkjoin/ contains samples that demonstratethe fork/join framework.

The ThreadLocalRandomclass eliminates contention among threads using pseudo-random numbers; see ConcurrentRandom Numbers.

The Phaserclass is a new synchronization barrier, similar to CyclicBarrier。

11. Java 2D

A new XRender-based Java 2D rendering pipeline is supported for modernX11-based desktops, offering improved graphics performance; see the xrenderflag in System Properties for Java 2D Technology.

The JDK now enumerates and displays installed OpenType/CFF fontsthrough methods such as GraphicsEnvironment.getAvailableFontFamilyNames; these fontsare also recognized by the Font.createFont method. See Selecting a Font.

The TextLayout class supports Tibetan script.

libfontconfig, a font configuration API, is used to select fonts to usefor the logical fonts for some implementations of Linux; see Fontconfig.

12. Internationalization

Unicode 6.0.0 is supported; see Unicode in The Java Tutorials.

The directory <Java home>/demo/jfc/Font2DTest/ contains samplesthat demonstrate Java support for Unicode 6.0.

Java SE 7 can accommodate new currencies that are identified by their ISO 4217 codes; see the Currency class.

13. Java Programming Language

The followingenhancements have been added to the Java language:

Binary Literals

Underscores in Numeric Literals

Strings in switch Statements

Type Inference for GenericInstance Creation

Improved Compiler Warnings andErrors When Using Non-Reifiable Formal Parameters with Varargs Methods

The try-with-resources Statement

Catching Multiple Exception Typesand Rethrowing Exceptions with Improved Type Checking

14. JDBC 4.1

JDBC 4.1introduces the following features:

The ability touse a try-with-resources statement toautomatically close resources of type Connection, ResultSet, and Statement; see Closing Connections in Processing SQL Statements.

RowSet 1.1:The introduction of the RowSetFactoryinterface and the RowSetProviderclass, which enable you to create all types of row sets supported by your JDBCdriver; see Using the RowSetFactory Interface in Using JdbcRowSet Objects.