ImageUtilities.loadImage第二个参数的说明

Pictures and icons used within an application are not loaded over the installer, but over a
central ImageUtilities class in the NetBeans world. The method loadImage() should be used.
An icon manager manages images and icons, preventing repeated loading of resources.
Use it to load icons from all available modules. It is also possible to load localized resources, as
in the following example. If the second parameter is set to true and there is an icon named
icon_de_DE.png available, then it is loaded (if the locale setting of application is de_DE):
Image img = ImageUtilities.loadImage("resources/icon.png", true);