Liferay Maven Service Builder Portlet(Developer Studio)

I am new in Liferay platform. I am trying to implement CRUD in Liferay using portlet. I am using liferay 6.2 and IDE as a developer studio.

I am creating project with below values (In Image) in developer studio.

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When I am creating project in Developer studio I am getting 3 project in my Liferay project explorer which are shown in below image.

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So my question is that why its three project are created when I only want to create one service builder portlet. What are the use of that?

Anyone can help?

Solution

So this is what Liferay with Maven does: It creates a Parent Project (BookServicePortlet). Liferay assumes, if you want to build a service layer, you also will implement a portlet where you access the Services generated. So that's why Liferay-Maven is creating 2 SubProjects in your parent project. One for the service, and one for Web-Tier. This is done, so that you can distribute your service layer to other portlets without distributing all your front-end code. If you don't have a front-end (and I doubt that ;) ) you could just leave all blank in BookServicePortlet-portlet.