A Profiler is nothing but, a tool which monitor the amout of memory uses by your IDE in creating various objects such as you created an object in your main class and you run that class then JVM allot some memory for that, in order to know how much memory it will use we use the profiler even it will show how much memory is available to JVM,how much it is alloted to the project right now and also about GC(garbage collector) stats and so forth.......
Using a profiler is quite easier first decide to which project you want to run the profiler and you should have to attach that profiler to that project. You will find the profiler in the menu bar profiler -> Attach Profiler. Then a dialog box appears First choice box select the project you want to attach the profiler after then on the left side of the dialog box you will see the list of thing that the profiler will do if you want you can customize the settings after then you can click on the attach profiler button.
Now go to the project and press right click on it and you get a popup menu in that ***************. If you click on it your project will run and you will see a lot of menu on the let side of your IDE below the files tab and you can press VMTelemetry view to see the stats of how much heap space is alloted to the JVM and how much it is using in different colors like this
Well creating a new project is quite easier and almost similar to other java IDE's. It is as simple as Go to File -> new -> project
After then a dialog box appears and asking you the name of the project and the name of the Main class you want for your project if you don't want that main class you can uncheck the box, if you don't uncheck it, it will create a new plane java class fo your project
Generally we write one or two java classes and run them. But when we are in the part of the Production Environment, we need to develop several classes and we need to integrate them to run the whole project. In order to develop and maintain such a big projects we generally use an Integrated Development Environment's(IDE). There are several IDE's available in the market such as Eclipse,Borland IDE and so on.I think oracle guys also have one java IDE. Likewise creators of java also developed one of the most user friendly and also having a lot of tools in that, it is nothing but the NetBeans IDE