Since I have a big project, I have to create UML for this. Writing UML for 300 classes is redundant.
So, is there any solution for creating diagrams for me?
PSI am using Netbeans.
Depending on what you need UML diagrams for, you can extract concepts from your "300 classes" and make UML diagrams yourself - perhaps this will also help find architectural flaws. Mass conversion of code to UML just for the purpose of having UML is usually not very desirable.
If you really need it, yes, Enterprise Architect is a good way. - classic.
I think Enterprise Architect with sparxx systems can create UML from Java classes
Try http://netbeans.org/features/uml/ It supports reverse code development. Of course, all you need to get is class diagrams.
I prefer to use Sybase Power Designer because it supports all types of UML diagrams. Please see wikipedia at http://en.wikipedia.org/wiki/PowerDesigner
PS: I do not advertise or associate with this company, but Power Designer has several features that I like.
I found easyUML useful. It is really easy to use.