Java origin of Java history

Java: A generic term for the Java programming language and Java platform introduced by Sun Microsystems Company in May 1995. The Java language, an object-oriented programming language that can compose cross-platform applications, was originally developed in the early 1990 by James Goslin James Gosling, a solar micro-system, initially named Oak. With the rapid development of the Internet, Java has gradually become an important network programming language.

It has been 19 years since the first version of Java was born. If time fleeting, fleeting. 19 years later, in the timeline shown, we see that the JDK has evolved to version 1.8. Over the past 19 years, countless Java-related products, technologies and standards have been born. Now let's go into the time tunnel, starting with the era of Java language, and reviewing the evolution of Java and its history.

　　

The green project, led by Dr. James Gosling, started in April 1991 to develop a program architecture that can run on a variety of consumer electronics, such as set-top boxes, refrigerators, radios, and so on. The product of this program is the predecessor of the Java language: Oak. Oak was not a success in the consumer goods market at the time, but with the advent of the Internet in the 1995, Oak quickly found the market position best suited to its own development and became the Java language.

The oak language was renamed Java on May 23, 1995, and the Java 1.0 version was officially released at the Sunworld convention. The Java language first presented the slogan "Write once,run Anywhere".

JDK 1.0 was released on January 23, 1996, and the Java language has the first official version of the runtime environment. JDK 1.0 provides a pure explanation for executing the Java Virtual machine implementation (Sun Classic VM). The JDK 1.0 version of the technology includes: Java Virtual machine, Applet, AWT and so on.

In April 1996, 10 of the most important operating system vendors affirmed that Java technology would be embedded in their products. In September, about 83,000 Web pages were created using Java technology. At the end of May 1996, Sun held its inaugural JavaOne conference in San Francisco, where JavaOne became the annual technology event for millions of Java language developers around the world.

On February 19, 1997, Sun released some of the most basic support points for JDK 1.1,java technology, such as JDBC, which were released in JDK version 1.1, and the technical representatives of JDK version 1.1 are: Jar file format, JDBC, JavaBeans, RMI. Java syntax also has some development, such as the Inner class (Inner Class) and reflection (Reflection) are present at this time.

Until April 8, 1999, JDK 1.1 released a total of nine versions of 1.1.0~1.1.8. After 1.1.4, each JDK version has its own name (Project code): JDK 1.1.4-sparkler (GEM), JDK 1.1.5-pumpkin (pumpkin), JDK 1.1.6-abigail (Abigail, woman name), JDK 1.1.7-brutus (Brutus, Roman statesman and general) and JDK 1.1.8–chelsea (Chelsea, city name).

December 4, 1998, JDK ushered in a milestone version of JDK 1.2, the project codenamed Playground (Arena), sun in this version of the Java technology system into 3 directions, respectively, for desktop application development j2se (Java 2 Platform , Standard Edition), Java 2 Platform, Enterprise Edition, and J2ME for mobile devices such as mobile phones (Java 2 Platform, Micro Edition) for business-level development. There are a number of representative technologies in this version, such as EJB, Java plug-in, Java IDL, swing, and so on, and this version of the Java Virtual machine is built with the JIT (Just in time) compiler first (there were 3 VMs in JDK 1.2. Classic VMS, HotSpot VMS, and exact VMS, where exact VMS only appear on the Solaris platform, and the last two virtual machines are built-in JIT compilers, whereas previous versions of classic VMs can only use the JIT compiler in the form of a plug-in. At the language and API levels, Java adds a series of collections collection classes that are most commonly used by the STRICTFP keyword and now Java encoding.

In March 1999 and July, there were JDK 1.2.1 and JDK 1.2.22 Iteration releases.

On April 27, 1999, the Hotspot virtual machine was released, and the hotspot was originally developed by a small company called "Longview Technologies", which was acquired by Sun in 1997 because of the outstanding performance of the Hotspot. The hotspot virtual machine was released as an add-on to JDK 1.2, and later it became the default virtual machine for all versions of JDK 1.3 and later Sun JDK.

May 8, 2000, the project codenamed Kestrel (American Red Falcon) JDK 1.3 released, JDK 1.3 compared to JDK 1.2 is mainly shown in some class libraries (such as mathematical operations and new timer API, etc.), Jndi service from the JDK 1.3 was started as a platform-level service (formerly Jndi was just an extension), using CORBA IIOP to implement RMI communication protocols, and so on. This version also makes a lot of improvements to the Java 2D, provides a number of new Java 2D APIs, and adds a new Javasound class library. JDK 1.3 has 1 modified versions of JDK 1.3.1, project codenamed Ladybird (Ladybug), released on May 17, 2001.

Since the beginning of JDK 1.3, Sun has maintained a habit of releasing a major version of the JDK every two years, named after the animals, and using insects as the project name for each modified version released.

February 13, 2002, JDK 1.4 was released, the project codenamed Merlin (the Gray-backed Falcon). JDK 1.4 is a really mature version of Java, and Compaq, Fujitsu, SAS, Symbian, IBM and other famous companies have to participate in and even realize their own independent JDK 1.4. Even today, more than 10 years later, there are still many mainstream applications (Spring, Hibernate, struts, etc.) that can run directly on top of JDK 1.4 or continue to release versions that run on JDK 1.4. JDK 1.4 also publishes a number of new technical features, such as regular expressions, exception chains, NIO, log classes, XML parsers, and XSLT converters.

JDK 1.4 has two follow-up revisions:

The project codenamed Grasshopper (Grasshopper), released on September 16, 2002, is a JDK 1.4.1

The project codenamed Mantis (Mantis), released on June 26, 2003, is the JDK 1.4.2.

There was also an event that was not directly related to Java around 2002, but it actually had a big impact on the Java development process, which was the release of Microsoft's. NET framework. This technology platform, both in technology implementation and on the target user, has many similarities with Java, which brings much discussion, comparison and competition to Java. The controversy between the net platform and the Java platform has continued so far.

September 30, 2004, JDK 1.5 released, Project Code Tiger (Tiger). Since JDK 1.2, Java has been transformed at a very small syntactic level, and JDK 1.5 has made a great improvement in the usability of Java syntax. For example, syntax features such as auto-boxing, generics, dynamic annotations, enumerations, variable-length parameters, traversal loops (foreach loops) are all included in JDK 1.5. At the virtual machine and API level, this version improves the Java memory model (Java Memory model,jmm), provides java.util.concurrent and contracts, and so on. In addition, JDK 1.5 is the official statement that can support the last JDK version of the Windows 9x platform.

December 11, 2006, JDK 1.6 released, Project Code Mustang (Mustang). In this release, Sun has ended the 8-year history of the Java EE, J2SE, and J2ME naming methods that started with JDK 1.2, enabling the naming of the JavaScript SE 6, Java EE 6, and Java ME 6. Improvements in JDK 1.6 include the provision of dynamic language support (implemented via the built-in Mozilla Java Rhino engine), the provision of compilation APIs, and the micro-HTTP Server API. At the same time, this version of the Java Virtual machine has made a lot of improvements, including lock and synchronization, garbage collection, class loading and other aspects of the algorithm has a considerable number of changes.

At the JavaOne conference on November 13, 2006, Sun announced that it would eventually open up Java, and in the next year or so, the various parts of the JDK in the GPL v2 (GNU general public License v2) under the agreement to open the source code, and the establishment of the OPENJDK organization of these sources of independent management. In addition to a very small number of property code (encumbered code, which is mostly sun itself does not have access to open source processing), OpenJDK almost all of the Sun JDK Code, OPENJDK quality director once said that in JDK 1.7, Sun JDK and OpenJDK In addition to the code file header of the copyright note, the code is basically exactly the same, so OpenJDK 7 and Sun JDK 1.7 is essentially the same set of code library development products.

After JDK 1.6 was released, Sun spent a lot of resources on things beyond JDK development due to increased code complexity, JDK open source, development JavaFX, the economic crisis, and Sun acquisitions, and the JDK update did not sustain the development of a major release for two years. JDK 1.6 has so far released 37 update versions, the latest version for the Java SE 6 update 37, released on October 16, 2012.

February 19, 2009, the project codenamed Dolphin (Dolphin) JDK 1.7 completed its first milestone version. A total of 10 milestones were set according to the functionality planning of JDK 1.7. The last milestone version was originally scheduled to end on September 9, 2010, but for various reasons, JDK 1.7 was eventually not completed as planned.

From the beginning of the JDK 1.7 feature plan, it was supposed to be a JDK version with many significant improvements, including lambda projects (lambda expressions, functional programming), Jigsaw projects (virtual machine modularity support), Dynamic language support, Sub-projects such as garbagefirst collectors and coin projects (Language detail evolution) will have a profound impact on the Java industry. During the development of JDK 1.7, sun was mired in technological competition and commercial competition, and the company's stock market value fell to only 3% of the peak period, and it was unable to push the development of JDK 1.7 to the normal plan. In order to end the long-term "skip ticket" for JDK 1.7, Oracle soon announced that it would implement a "Plan B", drastically tailoring the JDK 1.7 target to ensure that the official version of JDK 1.7 was released on July 28, 2011. Plan B Delays partial improvements to the Lambda project, jigsaw Project, and coin project that cannot be completed on time to JDK 1.8. Ultimately, the main improvements to JDK 1.7 include the provision of a new G1 collector (G1 is still in experimental state at the time of release, until the April 2012 Update 4 was formally "regularized"), and enhanced call support for non-Java languages (JSR-292, This feature has so far not been fully trained), the upgrade class loading architecture, and so on.

So far, JDK 1.7 has released 9 update versions, and the latest Java SE 7 update 9 was released on October 16, 2012. Starting with the Java SE 7 Update 4, Oracle has started to support the Mac OS X operating system and has achieved full support in Update 6, while also supporting the arm instruction set architecture in Update 6. At this point, the official JDK can run on Windows (without Windows 9x), Linux, Solaris, and Mac OS platforms, supporting ARM, x86, x64, and SPARC instruction set schema types.

April 20, 2009, Oracle announced the official acquisition of Sun Company at a price of $7.4 billion, the Java trademark is formally owned by Oracle (the Java language itself does not belong to which company owned, it is managed by the JCP organization, Although JCP is primarily led by Sun Inc. or Oracle Corporation. Since Oracle has acquired another large middleware company, BEA, after completing its acquisition of Sun, Oracle has made two of the three largest commercial virtual machines from Bea and Sun: JRockit and Hotspot, Oracle announces that in the next 1-2 years, the two outstanding virtual machines will complement each other and eventually merge into one. It is foreseeable that in the near future, Java Virtual Machine technology will have a considerable change.

July 28, 2011, Oracle releases Java SE 1.7

March 18, 2014, Oracle publishes Java SE 1.8

The Java language has the following features: Simple, object-oriented, distributed, interpreted execution, robust, secure, architecture-neutral, portable, high-performance, multithreaded, and dynamic. (specifically described in other chapters)

Java origin of Java history