Tuesday, 4 June 2013

Java version history

The Java language has undergone several changes since JDK 1.0 as well as numerous additions of classes and packages to the standard library. Since J2SE 1.4, the evolution of the Java language has been governed by the Java Community Process (JCP), which uses Java Specification Requests (JSRs) to propose and specify additions and changes to the Java platform. The language is specified by the Java Language Specification (JLS); changes to the JLS are managed under JSR 901.



In addition to the language changes, much more dramatic changes have been made to the Java class library over the years, which has grown from a few hundred classes in JDK 1.0 to over three thousand in J2SE 5. Entire new APIs, such as Swing and Java2D, have been introduced, and many of the original JDK 1.0 classes and methods have been deprecated.

1 JDK Alpha and Beta (1995)
2 JDK 1.0 (January 23, 1996)
3 JDK 1.1 (February 19, 1997)
4 J2SE 1.2 (December 8, 1998)
5 J2SE 1.3 (May 8, 2000)
6 J2SE 1.4 (February 6, 2002)
7 J2SE 5.0 (September 30, 2004)
8 Java SE 6 (December 11, 2006)
9 Java SE 7 (July 28, 2011)
10 Java SE 8



1) JDK Alpha and Beta (1995)
Alpha and Beta Java public releases had highly unstable APIs and ABIs. The supplied Java web browser was named WebRunner.

2) JDK 1.0 (January 23, 1996)
Codename Oak. Initial release The first stable version was the JDK 1.0.2. is called Java

3) JDK 1.1 (February 19, 1997)
Major additions included:

(3.1)an extensive retooling of the AWT event model
(3.2)inner classes added to the language
(3.4)JavaBeans
(3.5)JDBC
(3.6)RMI
(3.7)reflection which supported Introspection only, no modification at runtime was possible.
(3.8)JIT compiler on Microsoft Windows platforms, produced for JavaSoft by Symantec.

4)J2SE 1.2 (December 8, 1998)
Codename Playground. This and subsequent releases through J2SE 5.0 were rebranded retrospectively Java 2 and the version name "J2SE" (Java 2 Platform, Standard Edition) replaced JDK to distinguish the base platform from J2EE (Java 2 Platform, Enterprise Edition) and J2ME (Java 2 Platform, Micro Edition). This was a very significant release of Java as it tripled the size of the Java platform to 1520 classes in 59 packages. Major additions included:

(4.1)strictfp keyword
(4.2)the Swing graphical API was integrated into the core classes
(4.3)Sun's JVM was equipped with a JIT compiler for the first time
(4.4)Java plug-in
(4.5)Java IDL, an IDL implementation for CORBA interoperability
(4.6)Collections framework

5)J2SE 1.3 (May 8, 2000)
Codename Kestrel. The most notable changes were:

(5.1)HotSpot JVM included (the HotSpot JVM was first released in April, 1999 for the J2SE 1.2 JVM)
(5.2)RMI was modified to support optional compatibility with CORBA
(5.3)JavaSound
(5.4)Java Naming and Directory Interface (JNDI) included in core libraries (previously available as an extension)
(5.5)Java Platform Debugger Architecture (JPDA)
(5.6)Synthetic proxy classes

6)J2SE 1.4 (February 6, 2002)


Codename Merlin. This was the first release of the Java platform developed under the Java Community Process as JSR 59. Major changes included:
Language changes
(6.1)assert keyword

Library improvements
(6.2)regular expressions modeled after Perl regular expressions
(6.3)exception chaining allows an exception to encapsulate original lower-level exception
(6.4)Internet Protocol version 6 (IPv6) support
(6.5)non-blocking IO (named NIO) (New Input/Output)
(6.6)logging API
(6.7)image I/O API for reading and writing images in formats like JPEG and PNG
(6.8)integrated XML parser and XSLT processor (JAXP)
(6.9)integrated security and cryptography extensions (JCE, JSSE, JAAS)
(6.10)Java Web Start included (Java Web Start was first released in March, 2001 for J2SE 1.3)
(6.11)Preferences API (java.util.prefs)

7)J2SE 5.0 (September 30, 2004)

Codename Tiger. Originally numbered 1.5, which is still used as the internal version number.
J2SE 5.0 entered its end-of-public-updates period on April 8, 2008 updates are no longer available to the public as of November 3, 2009. Updates will be available to Oracle Customers until May 2014.

Tiger added a number of significant new language features:

(7.1)Generics: Provides compile-time (static) type safety for collections and eliminates the need for most typecasts (type conversion).
(7.2)Metadata: Also called annotations; allows language constructs such as classes and methods to be tagged with additional data, which can then be processed by
metadata-aware utilities.
(7.3)Autoboxing/unboxing: Automatic conversions between primitive types (such as int) and primitive wrapper classes (such as Integer).
(7.4)Enumerations: The enum keyword creates a typesafe, ordered list of values .
(7.5)Varargs: The last parameter of a method can now be declared using a type name followed by three dots ). In the calling code any number of parameters of that type can be used and they are then placed in an array to be passed to the method, or alternatively the calling code can pass an array of that type.
(7.6)Enhanced for each loop: The for loop syntax is extended with special syntax for iterating over each member of either an array or any Iterable, such as the standard Collection classes, using a construct of the form:

8)Java SE 6 (December 11, 2006)


Codename Mustang. As of this version, Sun replaced the name "J2SE" with Java SE and dropped the ".0" from the version number.

During the development phase, new builds including enhancements and bug fixes were released approximately weekly. Beta versions were released in February and June 2006, leading up to a final release that occurred on December 11, 2006.

Major changes included in this version:

(8.1)Support for older Win9x versions dropped; unofficially, Java 6 Update 7 was the last release of Java shown to work on these versions of Windows.[citation needed] This is believed[by whom?] to be due to the major changes in Update 10.
(8.2)Scripting Language Support (JSR 223): Generic API for tight integration with scripting languages, and built-in Mozilla JavaScript Rhino integration
(8.3)Dramatic performance improvements for the core platform, and Swing.
(8.4)Improved Web Service support through JAX-WS.
(8.5)JDBC 4.0 support.
(8.6)Java Compiler API : an API allowing a Java program to select and invoke a Java Compiler programmatically.
(8.7)Upgrade of JAXB to version 2.0: Including integration of a StAX parser.
(8.8)Support for pluggable annotations
(8.9)Many GUI improvements, such as integration of SwingWorker in the API, table sorting and filtering, and true Swing double-buffering (eliminating the gray-area effect).
(8.10)JVM improvements include: synchronization and compiler performance optimizations, new algorithms and upgrades to existing garbage collection algorithms, and application start-up performance.

9)Java SE 7 (July 28, 2011)


Java 7 (codename 'Dolphin') is a major update to Java that was launched on July 7, 2011 and was made available for developers on July 28, 2011.The development period was organized into thirteen milestones; on February 18, 2012, the last of the thirteen milestones was reached.On average, 8 builds (which generally included enhancements and bug fixes) were released per milestone. The feature list at the OpenJDK 7 project lists many of the feature changes.

Feature additions for Java 7 include:

(9.1)JVM support for dynamic languages, following the prototyping work currently done on the Multi Language Virtual Machine
(9.2)Compressed 64-bit pointers[83] (available in Java 6 with -XX:+UseCompressedOops)
(9.3)Small language changes (grouped under a project named Coin):

(9.3.1)Strings in switch
(9.3.2)Automatic resource management in try-statement
(9.3.3)Improved type inference for generic instance creation
(9.3.4)Simplified varargs method declaration
(9.3.5)Binary integer literals
(9.3.6)Allowing underscores in numeric literals
(9.3.7)Catching multiple exception types and rethrowing exceptions with improved type checking

(9.4)Concurrency utilities
(9.5)New file I/O library to enhance platform independence and add support for metadata and symbolic links. The new packages are java.nio.file and java.nio.file.attribute
(9.6)Library-level support for elliptic curve cryptography algorithms
(9.7)An XRender pipeline for Java 2D, which improves handling of features specific to modern GPUs
(9.8)New platform APIs for the graphics features originally implemented in version 6u10 as unsupported APIs
(9.9)Enhanced library-level support for new network protocols, including SCTP and Sockets Direct Protocol
(9.10)Upstream updates to XML and Unicode

10)Java SE 8
Java 8 is expected in March 2014 and will include at a minimum the features that were planned for Java 7 but later deferred.

(10.1): Language-level support for lambda expressions (officially, lambda expressions; unofficially, closures) under Project Lambda.[120] There was an ongoing debate in the Java community on whether to add support for lambda expressions.Sun later declared that lambda expressions would be included in Java and asked for community input to refine the feature.
(10.2)Parts of project Coin that are not included in Java 7
(10.3)Annotations on Java Types
(10.4)Date and Time API
(10.5)Tight integration with JavaFX