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I have an old Java web application that still uses Applets (not my decision).

After a recent Java upgrade (I believe it was 1.7 to 1.8) the app now throws a ClassNotFoundException and says that it can't find the JApplet class the Applet derives from before the Applet can load.

The path to the class is specified in a jsp page called loadApplet.jsp.

Here is the code in the loadApplet.jsp file. The only part that isn't an exact copy and paste is ThePathToTheJAppletClassWhichItAlwaysFoundBefore.class - which is just a string that defines where the package is.

<OBJECT classid = "clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" codebase = "https://java.sun.com/products/plugin/autodl/jinstall-1_4-windows-i586.cab#Version=1,4,0,0" height = "0" width = "0">
<PARAM NAME = "CODE"          VALUE = "ThePathToTheJAppletClassWhichItAlwaysFoundBefore.class" >
<PARAM NAME = "type"          VALUE = "application/x-java-applet;jpi-version=1.3.1" >
<PARAM NAME = "scriptable"    VALUE = "false" >

Andrew Thompson
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Tim Mitchell
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    See [Java Plugin support deprecated](http://www.gizmodo.com.au/2016/01/rest-in-hell-java-plug-in/) and [Moving to a Plugin-Free Web](https://blogs.oracle.com/java-platform-group/moving-to-a-plugin-free-web). Rather than chase down problems in this implementation, better to focus effort on **replacing** the applet. – Andrew Thompson Dec 01 '17 at 01:37
  • Sorry, but it's not up to me. – Tim Mitchell Dec 01 '17 at 01:43
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    There's no need to apologize to me, I'm not the one that has to suffer from trying to jerk applets into line anymore (and by 'anymore' I mean the effort that put me [at the top of this list](https://stackoverflow.com/tags/applet/topusers) & [this list](https://stackoverflow.com/tags/japplet/topusers)). If I were you, I'd let whoever made that decision know what it will **cost them**. That can sometimes bring them around to common sense. – Andrew Thompson Dec 01 '17 at 05:16
  • Since 7u21, Java plugin only load signed jars. https://stackoverflow.com/questions/16084324/java-applet-stopped-working-after-update-to-jre-7u21 – zakki Dec 05 '17 at 02:44

1 Answers1

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Thanks for all the suggestions. What happened was during the upgrade the Java Security settings were automatically set to Very High - thus the class on the client could not be found. I reset the setting to High and it worked fine.

Tim Mitchell
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