Applet on Browser - applet

Question

How I can use some functions that were declared on the applet class? i.e.
this is my class
public class hi extends JApplet{
public void HiThere(){
System.out.println("Hi on Java Console");
}
}
and on my browser it's declared something like:
<applet.... name="HI" id="HI" ......>Ooops!!!</applet>"
but when I tried to use the function there was a mistake, so how a can use the functions declared on my applet class?? Thanks!!!

Answer 1

First you should do this change to your code:
public class HI extends JApplet {
public HI() {System.out.println("Hi on Java Console");}
}
When you have done that, and your browser still has an error, then post the exact error message here. Also you might want to look for a tutorial "programming Java applets getting started", since your code tells me, that you don't seem to know what you are doing.

Answer 2

In order to call your class methods from js you must declare the <object> in html specifying a .jar or .class with your compiled content, the package of the main class and some other parameters like in the follow example (object is for IE, and embed is for FF):
I suppose that you want to invoke the hi.HiThere() method as defined in your question.
<object
width="100" height="100" id="hi">
<param name = "code" value = "path.to.your.main.class.hi">
<param name = "archive" value = "jar location">
<param name = "mayscript" value = "true">
<param name = "scriptable" value = "true">
...
<comment>
<embed
code = "path.to.your.main.class.hi"
archive = "your jar location"
scriptable = "true"
width = "100" height = "100"
name = "hi"
...
</embed>
</comment>
</object>
Then from the js you can access you object through the document using the id attribute in <object> or name in <embed> in the sample case document.hi. With the follow code you can invoke the HiThere(); method:
try{
// ie, ff
document.hi.HiThere();
}catch(Exception){
// chrome, safari, opera
document.hi[1].HiThere();
}
In order to execute with last java versions remember to meet the new java security requirements (manifest attributes http://docs.oracle.com/javase/tutorial/deployment/jar/manifestindex.html, jar signature... ).

Answer 3

You can call the applet methods in JavaScript:
To do this the applet should be launched from JavaScript, e.g.
<script src="https://www.java.com/js/deployJava.js"></script>
<script>
var attributes = { id: 'mainApplet', code:
'org.jazzteam.Example', archive: 'example.jar', width: 812, height:
635};
var parameters = {};
deployJava.runApplet(attributes, parameters, '1.7');
function actionInApplet(url) {
mainApplet.appletMethod(url);
}
</script>
In this case the applet is launched from JavaScript with id= 'mainApplet'. In the applet there is appletMethod() method, which we want to call. To do this you need to call the method related to JavaScript object with id name. You can also pass parameters to the called methods, as demonstrated in this example.
Also it is necessary to know that the applet method called from JavaScript should be privileged. To do this you need to wrap the method code in the following "wrapper":
AccessController.doPrivileged(new PrivilegedAction() {
public Object run() {
//method code
return new Object();
}
});
This information is taken from the article:
Frequently Asked Questions during Java applet development