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A Java applet is a small application which is written in Java and delivered to users in the form of bytecode. The user launches the Java applet from a web page, and the applet is then executed within a Java Virtual Machine (JVM) in a process separate from the web browser itself. A Java applet can appear in a frame of the web page, a new application window, Sun's AppletViewer, or a stand-alone tool for testing applets. Java applets were introduced in the first version of the Java language, which was released in 1995. Java applets can be written in any programming language that compiles to Java bytecode. They are usually written in Java, but other languages such as Jython,〔(【引用サイトリンク】title=Jython applet page )〕 JRuby,〔(About Java applets in Ruby )〕 Pascal,〔(【引用サイトリンク】title=Free Pascal Compiler for JVM )〕 Scala, or Eiffel (via SmartEiffel)〔(A tool to produce Java applets with SmartEiffel )〕 may be used as well. Java applets run at very fast speeds and, until 2011, they were many times faster than JavaScript.〔(【引用サイトリンク】title=An example of the 2005 year performance benchmarking )〕 Unlike JavaScript, Java applets had access to 3D hardware acceleration, making them well-suited for non-trivial, computation-intensive visualizations. As browsers have gained support for hardware-accelerated graphics thanks to the canvas technology (or specifically WebGL in the case of 3D graphics),〔(【引用サイトリンク】title=canvas - HTML )〕〔(【引用サイトリンク】title=WebGL - Web API Interfaces )〕 as well as just-in-time compiled JavaScript,〔(【引用サイトリンク】title=Design Elements - Chrome V8 )〕〔(【引用サイトリンク】title=JavaScriptCore )〕 the speed difference has become less noticeable. Since Java's bytecode is cross-platform (or platform independent), Java applets can be executed by browsers (or other clients) for many platforms, including Microsoft Windows, FreeBSD, Unix, OS X and Linux. == Overview == The Applets are used to provide interactive features to web applications that cannot be provided by HTML alone.They can capture mouse input and also have controls like buttons or check boxes. In response to user actions, an applet can change the provided graphic content. This makes applets well-suited for demonstration, visualization, and teaching. There are online applet collections for studying various subjects, from physics〔(【引用サイトリンク】title=Paul Falstad online applet portal )〕 to heart physiology.〔 An applet can also be a text area only; providing, for instance, a cross-platform command-line interface to some remote system.〔(【引用サイトリンク】title=Jraft.com )〕 If needed, an applet can leave the dedicated area and run as a separate window. However, applets have very little control over web page content outside the applet's dedicated area, so they are less useful for improving the site appearance in general (while applets like news tickers〔(ObjectPlanet.com ), an applet that works as news ticker〕 or WYSIWYG editors〔(Sferyx.com ), a company that produces applets acting as WYSWYG editor.〕 are also known). Applets can also play media in formats that are not natively supported by the browser.〔Cortado applet to play ogg format〕 Pages coded in HTML may embed parameters within them that are passed to the applet. Because of this, the same applet may have a different appearance depending on the parameters that were passed. As applets were available before CSS and DHTML were standard, they were also widely used for trivial effects such as rollover navigation buttons. Heavily criticized, this usage is now declining.〔(Top 13 ) Things Not to Do When Designing a Website〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Java applet」の詳細全文を読む スポンサード リンク
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