jdk 1.6新特性

http://www.oracle.com/technetwork/java/javase/features-141434.html原文章：

JavaSE 6技术变化集锦

JDK Documentation
Java Platform, Standard Edition 6 is a major feature release. The following list highlights many of the significant features and enhancements in Java SE 6 since the prior major release, J2SE 5.0. It is followed by a detailed table with links to related bugs, enhancements, and JSRs.

Note, this web page relates to the Release Candidate milestone for Java SE 6. Its related Umbrella JSR 270 does not itself define specific features. Instead it enumerates features defined in other JSRs or through the concurrent maintenance review of the Java SE platform specification. The final release is expected to include all JSR 270 features, although it is possible for an approved feature to be dropped.

Refer also to:
Java Platform, Standard Edition Differences between 5.0 fcs and 6 Beta .

Highlights of Technology Changes in Java SE 6

1.集合框架（Collections Framework）

2.部署Deployment (Java Web Start and Java Plug-in)

3.拖拽（Drag and Drop）

4.仪表（Instrumentation）

5.国际化支持（Internationalization Support）

6.I/O支持

7.JAR (Java Archive Files) - An annotated list of changes between the 5.0 and 6.0 releases to APIs, the jar command, and the jar/zip implementation

8.Java Web Start

9.Java DB 10.2 JDBC4 Early Access

The $JAVA_HOME/db subdirectory contains class libraries for Java DB, Sun Microsystems's distribution of the Apache Derby database technology.

• For information on Java DB, seehttp://www.oracle.com/technetwork/java/javadb/.

• For information on Derby, see:http://db.apache.org/derby/.

• For documentation on this version of Java DB, seehttp://www.oracle.com/technetwork/java/javadb/documentation/index.html.

• For a description of the capabilities of this version of Java DB, see the release notes in the $JAVA_HOME/db subdirectory.

• This Early Access version of Java DB is built from Apache Derby 10.2.1.7 source code (revision 453926) using JDK 6 JDBC 4 APIs to build JDBC 4 driver code.

• Comments regarding this version of Java DB can be sent [e-mail].

免责声明：这是早期访问软件是没有担保或支持。它提供了“是”。它不是生产使用。

DISCLAIMER: THIS IS EARLY ACCESS SOFTWARE AND COMES WITH NO WARRANTIES OR SUPPORT. IT IS PROVIDED "AS IS". IT IS NOT FOR PRODUCTION USE.

10.JMX (Java Management Extensions) - A list of JMX API changes between the J2SE 5.0 and Java SE 6 releases.

11.JPDA（Java平台调试架构Java Platform Debugger Architecture）

12.JVM TI (Java Virtual Machine Tool Interface)

13.lang and util 包（packages）

14.对Java平台的监控和管理Monitoring and Management for the Java Platform

15.Java SE 6正式支持JConsole（JConsole is Officially Supported in Java SE 6）

16.网络特性Networking Features

17.性能Performance

18.反射Reflection

19.RMI (Remote Method Invocation)

20.Scripting

21.Security

22.对象序列化Serialization of Objects

23.swing

24.VM (Java Virtual Machine)

以下条目由区/组件排序。第一列表示变化范围：

Items are ordered by area/component. The first column indicates the scope of a change:

jsr – A larger feature or feature set having its own Java Specification Request
api – A smaller feature that adds new Java APIs (application programming interfaces)
imp – An implementation enhancement that does not involve new APIs, for example, a performance improvement

SCOPE AREA/
COMPONENT SYNOPSIS RFE

api	client/2d	ImageIO: GIF writer	4339415
imp	client/2d	Native Text Rendering Parity	4726365
imp	client/2d	Improved hardware acceleration on Windows	5104393
imp	client/2d	Single-threaded rendering for OpenGL pipelines	6219284
api	client/awt	Pop-up splash screen at beginning of Java startup	4247839
api	client/awt	Java applications can access desktop applications	6255196
api	client/awt	Improved modal dialogs	4080029
imp	client/awt	XAWT is the default Toolkit on Solaris	5049146
api	client/awt	Windows system-tray support	4310333
imp	client/awt	Better support for input in non-English locales	4360364
imp	client/awt	Live resizing	6199167
imp	client/deploy	Improved application deployment across browsers	6329487
api	client/deploy	Allow JAR files to be shared across installed JREs	6271065
imp	client/deploy	Improved user experience in JRE/JDK installer	5079209
imp	client/deploy	Improved security	6222485
imp	client/deploy	Direct execution of JAR files on Linux	6211008
imp	client/deploy	Improved desktop integration in Java Web Start	4625362
imp	client/deploy	Improved IFTW installer	6198632
imp	client/deploy	Improved startup & footprint for plugin/webstart	6329480
imp	client/deploy	Mozilla Firefox browser support	6216340
imp	client/deploy	Default Java on Linux	6211006
imp	client/deploy	Improved user experience in Java Plug-in and Java Web Start	6205064
imp	client/deploy	Unified download engine	4802551
imp	client/deploy	Support Mozilla and Firefox family browsers.	6216340
api	client/dnd	A way to avoid hangs on retrieval of clipboard data	4818143
imp	client/i18n	Support for important locales	4324505
imp	client/i18n	Japanese calendar	4609228
api	client/i18n	Resource bundle enhancements	5102289
api	client/i18n	Normalizer API	4221795
api	client/i18n	Pluggable locales: Pluggability for break iterators	4052440
api	client/i18n	Pluggable locales: Pluggability for locale names, formatters, and collators	4052440
imp	client/l10n	Chinese localization for JDK tools	6209342
imp	client/swing	GTK Native L&F Fidelity	6185456
imp	client/swing	Through-the-stack: Reduced footprint / startup time	6329480
imp	client/swing	Native look & feel fidelity
imp	client/swing	Avalon Look-and-Feel	6329475
api	client/swing	JTable sorting, filtering, and highlighting	4747079
api	client/swing	JTabbedPane: Tabs as Components	4499556
imp	client/swing	Windows native L&F fidelity	5106661
api	client/swing	SwingWorker	4681682
api	client/swing	Improve Drag & Drop features for Swing Components	4468566
api	client/swing	Extend SpringLayout	4726194
api	client/swing	Text Document Printing	4791649
imp	client/swing	Improved Painting Performance (fix grey boxes)	4967886
jsr	core/core	JSR 223: Scripting for the Java Platform	6249843
api	core/debug	Multiple Simultaneous Agents	4772582
api	core/debug	Added Heap Capabilities to JPDA	4914266
api	core/debug	Attach-on-demand	6173612
api	core/debug	JVMPI and JVMDI have been removed.	4914266
api	core/jndi	Read-timeout specification for LDAP operations	6176036
api	core/libs	Array Reallocation API	4655503
imp	core/libs	BigDecimal optimizations for specjbb++
api	core/libs	Floating point: Add IEEE 754 recommended functions to java.lang.{{,Strict}Math}	4406429
api	core/libs	Standard service-provider API (java.util.Service)	4640520
api	core/libs	Collections and Concurrency Updates	6268386
api	core/libs	IO Enhancement: Password Prompting	4050435
api	core/libs	IO Enhancement: File Attributes	6216563
api	core/libs	IO Enhancement: Method for Discovering Free Disk Space	4057701
imp	core/libs	IO Enhancement: Long pathnames on Windows	4403166
api	core/libs	Low-level Java compiler API for IDEs	4813736
jsr	core/libs	JSR 202: Java Class File Specification Update	4639391
jsr	core/libs	JSR 199: Java compiler API	4164450
imp	core/libs	Improved perceived footprint	6280693
api	core/libs	Deques	6192552
api	core/libs	Navigable Maps and Sets	4155650
imp	core/libs	BitSet Updates	4963875,4979017,4979028,4979031,5030267,6222207,6404711
imp	core/libs	Performance Improvements when compiling using network file systems	4770745
imp	core/m&m	Improved diagnosability of OutOfMemoryError	6173515
api	core/m&m	Generic annotations for MBean descriptor contents	6221321
api	core/m&m	Support for java.util.concurrent locks in the lock related facility	5086470
imp	core/m&m	jconsole is more user-friendly	6174397
api	core/m&m	Small-scale improvements to JMX Monitor API	6222961
api	core/m&m	descriptors added to all types of MBean	6204469
api	core/m&m	MXBeans added to JMX	6175517
api	core/net	Light-weight HTTP server	6270015
api	core/net	Internationalized resource identifiers	5085902
api	core/net	Default CookieManager implementation	6244040
imp	core/net	SPNEGO HTTP authentication	6260531
api	core/net	International domain names	4737170
api	core/net	Programmatic access to network parameters	4691932
imp	core/sec	Native platform GSS integration	6202035,6345202
imp	core/sec	SPNEGO in Java GSS	6239635
imp	core/sec	MS CAPI Keystore provider	6318171
imp	core/sec	Better support for NSS keystore	6273877
imp	core/sec	Improved Policy performance	5037004
imp	core/sec	JSR 268: Java Smart Card I/O API	6239117
jsr	core/sec	JSR 105: XML DSig	4635230
api	core/sec	Enhance certificate APIs	4635060
jsr	core/tools	JSR 269: Standard pluggabilty API for annotation processors (APT)	6222574
imp	core/tools	javac: Support for split verification	6227862,6227862,5110170,5110184,6217263
imp	core/tools	javac: ImplementJSR 175'sjava.lang.SuppressWarnings	4986256
imp	core/tools	Class-path wildcards	6268383
jsr	ee/ee	JSR 250: Common annotations	6304697
imp	ee/jdbc	Extended JDBC-ODBC bridge to enable JDBC 4.0 EoD features	6290312
jsr	ee/jdbc	JSR 221: JDBC 4.0	6290312
imp	ee/xml	JAXP 1.4 JSR 206: Java API for XML Processing	6317994
jsr	ee/xml	Support for the Web Services stack JSR 222: JAXB 2.0 JSR 224: JAX-RPC 2.0 JSR 173: STAX JSR 181: Web Services Metadata	6245626
api	ee/xml	JavaBeans Activation Framework (JAF)	6254474
imp	vm/compilers	Improved performance of compiled code	5079711,6206844,6239807,4850474, 5003419,5004907,5101346,6190413,6191063, 6196383,6196722,6211497,6232485,6233627,6245809, 6251002,6262235,
imp	vm/c1	Linear scan register allocator for C1	6320351
imp	vm/c2	Improved loop optimization	5073662,5074608,5091921,6260293
imp	vm/c2	Escape analysis	6339956
imp	vm/c2	Lock coarsening	6245809
imp	vm/gc	CMS: Parallelize concurrent marking
imp	vm/gc	Parallel compaction
imp	vm/runtime	Improve uncontended synchronization performance
imp	vm/runtime	Improved performance of contended synchronization operations
imp	vm/runtime	Faster format checker/class-file parser
imp	vm/runtime	Improved startup time	6179212
imp	vm/runtime	Improved runtime performance
imp	vm/runtime	Improved JNI performance	5086424
imp	vm/runtime	Class circularity detection	4699981
imp	vm/runtime	DTrace support in the VM

一、Collections Framework Enhancements

概述Java SE 6中对集合框架的增强（This page summarizes enhancements to the collections framework in Java SE 6.）

这个版本比5 API看到变化较少，但更多的是对规范的准确和清晰的焦点。我们建议您使用JavaSE6规范，即使编写程序的版本。

（This release saw fewer API changes than 5.0, but there was more of a focus on the accuracy and clarity of the specification. We recommend using the Java SE 6 specification even when writing programs for older releases.）

API的变化的主要主题是更好的双向集合访问。

The primary theme of the API changes wasbetter bi-directional collection access.

These new collection interfaces are provided:

• Deque- adouble ended queue, supporting element insertion and removal at both ends. Extends theQueueinterface.双端队列，支持元素两端插入和去除。继承Queue接口。
• BlockingDeque- aDequewith operations that wait for the deque to become non-empty when retrieving an element, and wait for space to become available in the deque when storing an element. Extends both theDequeandBlockingQueueinterfaces. (This interface is part ofjava.util.concurrent.)
• NavigableSet- aSortedSetextended with navigation methods reporting closest matches for given search targets. ANavigableSetmay be accessed and traversed in either ascending or descending order. This interface is intended to supersede theSortedSetinterface.
• NavigableMap- aSortedMapextended with navigation methods returning the closest matches for given search targets. ANavigableMapmay be accessed and traversed in either ascending or descending key order. This interface is intended to supersede theSortedMapinterface.
• ConcurrentNavigableMap- aConcurrentMapthat is also aNavigableMap. (This interface is part ofjava.util.concurrent.)

The following concrete implementation classes have been added:

• ArrayDeque- efficient resizable-array implementation of theDequeinterface.
• ConcurrentSkipListSet- concurrent scalable skip list implementation of theNavigableSetinterface.
• ConcurrentSkipListMap- concurrent scalable skip list implementation of theConcurrentNavigableMapinterface.
• LinkedBlockingDeque- concurrent scalable optionally bounded FIFO blocking deque backed by linked nodes.
• AbstractMap.SimpleEntry- simple mutable implementation ofMap.Entry
• AbstractMap.SimpleImmutableEntry- simple immutable implementation ofMap.Entry

These existing classes have been retrofitted to implement new interfaces:

• LinkedList- retrofitted to implement theDequeinterface.
• TreeSet- retrofitted to implement theNavigableSetinterface.
• TreeMap- retrofitted to implement theNavigableMapinterface.

Two new methods were added to theCollectionsutility class:

• newSetFromMap(Map)- creates a general purposeSetimplementation from a general purposeMapimplementation.

  There is noIdentityHashSetclass, but instead, just use

  Set<Object> identityHashSet=
      Collections.newSetFromMap(
          new IdentityHashMap<Object, Boolean>());
  

• asLifoQueue(Deque)- returns a view of aDequeas a Last-in-first-out (Lifo)Queue.

TheArraysutility class now has methodscopyOfandcopyOfRangethat can efficiently resize, truncate, or copy subarrays for arrays of all types.

Before:

int[] newArray = new int[newLength];
System.arraycopy(oldArray, 0, newArray, 0, oldArray.length);

After:

int[] newArray = Arrays.copyOf(a, newLength);

待续