Applet CLASS_NOT_FOUND_EXCEPTION
Question
let's, create applet and add it to jsp page, environment in use is STS Spring Tool Suite
create New -> Dynamic Web Project -> name="WEBtest"
Java Resources -> src-> new packeg="firstPack.secondPack.mainPack.appletPack" -> new class="MyApplet"
package firstPack.secondPack.mainPack.appletPack;
import java.awt.Color;
import javax.swing.JApplet;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class MyApplet extends JApplet {
@Override
public void init() {
super.init();
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
populateGUI();
}
});
} catch (Exception e) {
System.err.println("createGUI didn't complete successfully");
}
}
void populateGUI(){
JPanel panel=new JPanel();
panel.setBackground( Color.LIGHT_GRAY);
panel.add(new JLabel("QUAQ-QUAQ"));
add(panel);
this.revalidate();
}
}
Run As -> Java Applet
Ok it works
web.xml was created automatically
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>WEBtest</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
</web-app>
so...
Web Content -> new jsp="default"
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<h6>DUCK</h6>
<h6>First TRY</h6>
<applet code="firstPack.secondPack.mainPack.appletPack.MyApplet"></applet>
<h6>Second TRY</h6>
<object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93">
<param name="code"
value="firstPack.secondPack.mainPack.appletPack.MyApplet">
</object>
<h6>Third TRY</h6>
<embed code="firstPack.secondPack.mainPack.appletPack.MyApplet"
type="application/x-java-applet;version=1.6" />
<h6>Fourth TRY</h6>
<object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93">
<param name="code"
value="firstPack.secondPack.mainPack.appletPack.MyApplet">
<comment> <embed
code="firstPack.secondPack.mainPack.appletPack.MyApplet"
type="application/x-java-applet;version=1.6">
<noembed> No Java Support. </noembed>
</embed> </comment>
</object>
</body>
</html>
now drag and drop our project in "Server"
server is default to STS: "Privotal tc Server Developer Edition v3.1"
start the server
open browser at http://localhost:8080/WEBtest/
click on window
click on Details
CLASS_NOT_FOUND_EXCEPTION
here some project setting
since everything from "src" go to "WEB-INF/classes" then i assume that "code" parameter in applet is OK
nevertheless i also tried to extract java file into JAR, and add "archive" parameter, but yet CLASS_NOT_FOUND_EXCEPTION
i deleted all java version on PC, then installed Java SE Development Kit 8 Update 40 (64 bit),it also installed Java 8 Update 40 (64 bit)
after, i tried to open some example of applet from docs.oracle.com yet failed, thus it asked me to install Java 8 Update 40 without 64bit, so now i have both, but since applet examples works fine i doubting this is the problem and left it as it is
at the end of second day of googling i'm kinda desperate, yet it's important to make it work
2 answers
solution1
1 2015-04-11 10:35:13
since everything from "src" go to "WEB-INF/classes" then i assume that "code" parameter in applet is OK
Only the server has access to the WEB-INF/classes and WEB-INF/lib paths. If you try to make a direct fetch on the applet (using the browser address bar) you'll likely see a 'forbidden' page.
solution2
0 ACCPTED 2015-04-17 10:12:00
applet should be public content, by typing its URL in browser we should be able to download it
to achieve this should be enough to modify "Deployment Assembly" so ..
First Try
Project -> Property - > Deployment Assembly - > Source ( java resources folder "/src") -> Deploy Path ( change to root directory )
ok now it works
Now restore "src" folder to "WEB-INF/classes" (for server side purpose)
Create new source folder "appletSRC", change it Deployment Assembly to "root directory" and for some reason it doesn't work
If in project property change "Order and Export" part by pushing
"appletSRC" -> UP
it's possible to make applet work, but then "src" (which first was on the top) will not be deployed in "WEB-INF/classes".
Nevertheless Ultimate solution
Project -> Property - > Java Build Path -> Source -> appletSRC -> Output folder -> Edit
set to public folder in "webapp"
when declaring applet tag specify in the "archive" our public folder
Important finish "archive" with /slash, and code with .class extension otherwise if refreshing browser several times it will give error
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