I am developing a java web application and that includes an applet. That applet is dependent on two jar files:
- JFreeChart (for plotting graphs at the client side) - 1.7 mb(size of jar file)
- MySqlJdbcConnector (for storing data, captured at the client side, to a remote database) - .7 mb (size of jar file)
Now, the problem is the size of above two jar files. The total size of my applet jar (myApplet.jar) is 2.5 mb out of which 2.4 mb is because of the above two jar files.
I am not using all the classes in those jar files. Specifically, for jfreechart, I am using a very small number of classes from that library.
Q1. For creating myApplet.jar file, what I have done is I have unzipped both of the jar files (jfreechart and mySQLJdbcConnector) and then packed the unzipped version of the jar files with the source code of my applet code to create one single jar file (i.e myApplet.jar). Is it the correct way of packing third party jar files with your applet code? Is there any way by which I can optimize this?
Q2. I tried to find the dependencies of the classes of jfreechart library which I am using in my application so as to pack only those dependencies in myApplet.jar. For that purpose, I used DependencyAnalyzer to find the dependencies of all the classes. But later I found it difficult to do so manually because every class (class of jfreechart that I am using in my application) has lot of dependencies and I am using some 15 classes of jfreechart so doing this for every class will be very difficult. So any suggestion on this?
Q3. Is this situation very common that developers encounter or I am missing something because of which I have to do this?
You can create an ant script or use Eclipse or any other IDE to automatically package your applet. But your way is correct, too
I wouldn't do these things manually. Finding transitive dependencies is very complex. Maybe darioo's answer is a better way to do this.
This is very common indeed. A couple of hints:
You can always re-build those third party libraries without debug information. That should slightly decrease the size of those libraries.
On the other hand, maybe you shouldn't have a direct connection from your applet to a database. You could create an RMI interface (or something similar) to transfer your SQL and result data to an application server, which actually executes your SQL. This is an important security aspect for your applet, if you don't run this in a safe intranet.