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With Java Library Project, you can refer a jar file or a project in your workspace and make it a bundle which will be available in to bundle classpath during the runtime. To create a Java Library Project, open WSO2 Developer Studio Dashboard and select Java Library Project from Carbon category.
Give a name to the project and click Next.
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With the second option, it will list all the available projects in the workspace and you can select the project you want to create a Java Library dependency.
You can add multiple jars and projects for a single Java Library Project. Once you add needed jars and projects, click Next if you want to add a parent project's POM information to this project's POM, or just click Finish.
Now you will see Library Project has been created in the workspace. You can create a bundle out of that project by exporting it in to a deployable archive. To do that right click on the project and select Export Project as Deployable Archive.
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To create a Carbon UI Bundle Project, open WSO2 Developer Studio Dashboard and select Carbon UI Bundle Project from Carbon category. 
You can create a Carbon UI Bundle Project in two different ways.
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With New Carbon UI Bundle option, you will create a new bundle project from the scratch. In the wizard page, you will see an entry called Deploy Path with entries to enter other necessary information. Deploy Path is the path where you specify all your resources like jsp files, html files etc. Give the necessary information and then click if you want to add a parent project's POM information to this project's POM, or just click Finish.
Now you will see new Carbon UI Bundle Project has been created in the workspace.
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