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This article introduces how the Java Applet program development steps are, and the content is very detailed. Interested friends can use it for reference. I hope it will be helpful to you.

Java first dedicated to the world is Java Applet, and then it attracted the attention of the world. Java Applet runs on the browser, can generate vivid and beautiful pages, friendly human-computer interaction, but also can deal with images, sound, animation and other multimedia data. Java Applet has played an immeasurable role in the growth of Java. Today, Java Applet is still one of the most attractive people in Java programming. In this installment, I will introduce readers to some of the techniques of Java Applet programming.

Introduction to Java Applet

Java Applet is some small applications written in Java language. These programs are directly embedded in the page and are interpreted and executed by browsers (IE or Nescape) that support Java. It can greatly improve the interactive ability and dynamic execution ability of Web pages. Web pages that contain Java Applet are called Java-powered pages, and can be called Java-supported pages.

When a user visits such a web page, Java Applet is downloaded to the user's computer for execution, but only if the user is using a web browser that supports Java. Because Java Applet is executed on the user's computer, its execution speed is not limited by network bandwidth or Modem access speed, and users can better appreciate the multimedia effects produced by Java Applet on web pages.

The implementation of Java Applet applet mainly depends on java. The Java Applet class in the Applet package. Unlike normal applications, Java Applet applications must be embedded in HTML pages in order to be interpreted and executed; at the same time, Java Applet can obtain parameters from Web pages and interact with Web pages.

The HTML file code for a web page with Java Applet must have a pair of tags such as < Java Applet > and < / Java Applet >, and when a web browser that supports Java encounters these tags, it will download the corresponding Mini Program code and execute the Java Applet Mini Program on the local computer.

Java Applet is a Mini Program of Java, which is downloaded and run by a web browser that supports Java by using the HTML file of the Java Applet. It can also be run through the Java Appletviewer of the java development tool. The Java Applet program can't do without the HTML file that uses it. The information about Java Applet in this HTML file should contain at least the following three points:

1) bytecode file name (compiled Java file with .class suffix)

2) address of bytecode file

3) the way to display Java Applet on a web page.

Adding Java Applet-related content to a HTML file only makes the web page more vibrant, such as adding attractive features such as sound and animation, and it does not change the elements in the HTML file that have nothing to do with Java Applet.

Java Applet program development steps

The main steps of Java Applet program development are as follows:

1) choose tools such as EDIT or WindowsNotepad as editor to establish Java Applet source program.

2) convert the source program of Java Applet into bytecode file.

3) compiling HTML files using class. Put the necessary < Java Applet > statements in the HTML file.

Here is the simplest example of HelloWorld to illustrate the development process of a Java Applet program:

(1) Edit the java source file of Java Applet

Create a folder C:\ ghq and create a HelloWorld.java under this folder

The source code of the file is as follows:

Importjava.awt.*; importjava.Java Applet.*; publicclassHelloWorldextendsJava Applet// inherits the Appelet class, which is a feature of AppeletJava programs {publicvoidpaint (Graphicsg) {g.drawString ("HelloWorld!", 5jm 35);}}

Save the above program in the C:\ ghq\ HelloWorld.java file.

(2) compile Java Applet

The following JDK command can be used to compile the HelloWorld.java source file:

C:\ ghq\ > javacHelloWorld.java < Enter >

Note: if you write a source program that violates the syntax rules of the Java programming language, the Java compiler will display a syntax error message on the screen. The source file must not contain any syntax errors for the Java compiler to successfully convert the source program into bytecode programs that Java Appletviewer and browsers can execute.

A file that generates the bytecode file HelloWorld.class for the response after a successful compilation of Java Applet. If you list the directories with the Explorer or DIR command, you will find an additional file named HelloWorld.class in the directory C:\ ghq.

(3) create HTML file

Before running the created HelloWorld.class, you also need to create a HTML file through which the Java Appletviewer or browser will access the created Java Applet. To run HelloWorld.class, you need to create a file named HelloWorld.html that contains the following HTML statement.

< HTML > < TITLE > HelloWorldwide Java Applet < / TITLE > < Java Applet CODE= "JavaWorld.class" WIDTH=200 HEIGHT=100 > < / Java Applet > < / HTML >

In this example, the < Java Applet > statement indicates the file name of the Java Applet bytecode class and the size of the window in pixels. Although the file name used by the HTML file here is HelloWorld.HTML, which corresponds to the name of HelloWorld.java, this correspondence is not necessary and the HTML file can be named with any other name (such as Ghq.HTML). However, keeping a corresponding relationship between file names can bring convenience to the management of files.

(4) execute HelloWorld.html

If you run HelloWorld.html with Java Appletviewer, enter the following command line:

C:\ ghq\ > Java AppletviewerJavaWorld.html < ENTER >

As you can see, this command starts Java Appletviewer and indicates the HTML file, which contains the < Java Applet > statement corresponding to HelloWorld.

If you run HelloWorldJava Applet with a browser, enter the URL address of the HTML file in the address bar of the browser.

At this point, the whole process of developing and running a Java Applet program is over (including java source files, compiled class files, html files, and running with Java Appletviewer or browser).

About how the Java Applet program development steps are shared here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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