Applet embed tag is returning ClassNotFoundException

问题

I have an applet jar file cia.jar and the class in it main.class and I have my class in the package com.gmail.connorbphtml.WebApp. I am trying to embed my applet into a webpage. When I am trying to do this I get a class not found error.

The applet works fine in Eclipse but then when I try to embed it it does not work.

Here is my HTML using embed:

<embed code="main.class"
archive="cia.jar"
width="200" height="200"
type="application/x-java-applet;version=1.6.0"
pluginspage="http://java.sun.com/javase/downloads"/>

I have been having this problem for months which made me give up applets because I can't get this working.

Does anyone know what went wrong?

The results from jar -tvf cia.jar are:

39 Sun Sep 16 12:34:50 EDT 2012 META-INF/MANIFEST.MF
     0 Sat Sep 15 18:02:30 EDT 2012 com/
     0 Sat Sep 15 18:02:30 EDT 2012 com/gmail/
     0 Sat Sep 15 18:02:30 EDT 2012 com/gmail/connorbphtml/
     0 Sat Sep 15 18:02:30 EDT 2012 com/gmail/connorbphtml/WebApp/
   136 Sat Sep 15 18:02:16 EDT 2012 com/gmail/connorbphtml/WebApp/package-info.class
   692 Sat Sep 15 23:26:08 EDT 2012 com/gmail/connorbphtml/WebApp/main.class
   226 Sat Sep 15 18:01:20 EDT 2012 .classpath
   366 Sat Sep 15 18:01:20 EDT 2012 .project

The error in the console:

Java Plug-in 1.6.0_33
Using JRE version 1.6.0_33-b03-424-11M3720 Java HotSpot(TM) 64-Bit Server VM
User home directory = /Users/Connor

----------------------------------------------------
c:   clear console window
f:   finalize objects on finalization queue
g:   garbage collect
h:   display this help message
l:   dump classloader list
m:   print memory usage
o:   trigger logging
q:   hide console
r:   reload policy configuration
s:   dump system and deployment properties
t:   dump thread list
v:   dump thread stack
x:   clear classloader cache
0-5: set trace level to <n>
----------------------------------------------------

Java Plug-in 1.6.0_33
Using JRE version 1.6.0_33-b03-424-11M3720 Java HotSpot(TM) 64-Bit Server VM
User home directory = /Users/Connorload: class Sun_Microsystems_Java_Security_Update_6.class not found.
java.lang.ClassNotFoundException: Sun_Microsystems_Java_Security_Update_6.class
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Applet2ClassLoader.java:252)
load: class com/gmail/connorbphtml/WebApp/main.class not found.
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Plugin2ClassLoader.java:249)
load: class com/gmail/connorbphtml/WebApp/main.class not found.
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:179)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:160)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Plugin2ClassLoader.java:690)
    at sun.plugin2.applet.Plugin2Manager.createApplet(Plugin2Manager.java:3045)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Plugin2Manager.java:1497)
    at java.lang.Thread.run(Thread.java:680)
Exception: java.lang.ClassNotFoundException: Sun_Microsystems_Java_Security_Update_6.class
java.lang.ClassNotFoundException: com.gmail.connorbphtml.WebApp.main.class
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Applet2ClassLoader.java:252)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Plugin2ClassLoader.java:249)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:179)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:160)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Plugin2ClassLoader.java:690)
    at sun.plugin2.applet.Plugin2Manager.createApplet(Plugin2Manager.java:3045)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Plugin2Manager.java:1497)
    at java.lang.Thread.run(Thread.java:680)
Exception: java.lang.ClassNotFoundException: com.gmail.connorbphtml.WebApp.main.class
java.lang.ClassNotFoundException: com.gmail.connorbphtml.WebApp.main.class
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Applet2ClassLoader.java:252)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Plugin2ClassLoader.java:249)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:179)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Plugin2ClassLoader.java:160)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Plugin2ClassLoader.java:690)
    at sun.plugin2.applet.Plugin2Manager.createApplet(Plugin2Manager.java:3045)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Plugin2Manager.java:1497)
    at java.lang.Thread.run(Thread.java:680)
Exception: java.lang.ClassNotFoundException: com.gmail.connorbphtml.WebApp.main.class

回答1:

Use deployJava.js to write the element for the applet.

E.G. adapted from the page:

<script src="http://www.java.com/js/deployJava.js"></script>
<script>
    var attributes = {codebase:'.',
                      code:'com.gmail.connorbphtml.WebApp.main',
                      archive:'cia.jar',
                      width:200, height:200};
    var version = '1.6';
    deployJava.runApplet(attributes, parameters, version);
</script>

The script will write the appropriate element in the correct form for the browser/OS on which it is running.

回答2:

Code should not contain .class extension. Try this.

<applet code="com.gmail.connorbphtml.WebApp.main" archive="cia.jar"
width="200" height="200"></applet>

Also you did not include the package name in the code attribute.

来源：https://stackoverflow.com/questions/12444581/applet-embed-tag-is-returning-classnotfoundexception

标签

java

html

google-chrome

applet

classnotfoundexception