Illegalstateexception | Tech Tips & Tricks

Tag: illegalstateexception

JQuery hide() Messes Up Applet State, Gives IllegalStateException

September 11, 2013 by blogmeister·0 Comments

Seems like an applet that is inside a DOM container and getting hidden by calling JQuery’s hide() method messes up the applet’s state.

In my case, I got an IllegalStateException and in some cases forced it to restart the applet which in turned messed up the operation that my code is doing.

I used the deployJava.js script to deploy the applet and enable me to call applet methods from Javascript.

So rather than using hide, user Danny Coulombe of StackOverflow gave a very workable solution. Using CSS, you can use JQuery to add the class attribute to hide or show the applet. See code.

.hide {
    position: absolute;
    left: -10000px;
}

.hide {

position: absolute;

left: -10000px;

}

To hide, call $(‘myapplet’).addClass(‘hide’).

To show, call $(‘myapplet’).removeClass(‘hide’).

A very useful solution to preserve your applet state in case you wish to hide it from the user’s view and show it later on using the same instance.

Fixing The “Invalid use of SingleClientConnManager: connection still allocated” Problem

May 5, 2011 by blogmeister·6 Comments

I came upon this problem because the site I wanted to access had server problems, meaning the website was down. When my code tried to access it again, it gave out this “Invalid use of SingleClientConnManager: connection still allocated” exception message.

My code uses Apache’s HttpClient 3rd party library and I thought at first calling the consumeContent() method of the HttpEntity class did the trick since I never even closed the InputStream when getting a reference to it. It did not.

Luckily, after much surfing I stumbled upon Jason Hudgin’s site where he created a convenience method that avoids this problem.

public static DefaultHttpClient getThreadSafeClient() {
    DefaultHttpClient client = new DefaultHttpClient();
    ClientConnectionManager mgr = client.getConnectionManager();
    HttpParams params = client.getParams();
    client = new DefaultHttpClient(new ThreadSafeClientConnManager(params, 
            mgr.getSchemeRegistry()), params);
    return client;
}

public static DefaultHttpClient getThreadSafeClient() {

DefaultHttpClient client = new DefaultHttpClient();

ClientConnectionManager mgr = client.getConnectionManager();

HttpParams params = client.getParams();

client = new DefaultHttpClient(new ThreadSafeClientConnManager(params,

mgr.getSchemeRegistry()), params);

return client;

}