Java
Since Java version 1.8.0-211 Oracle change to a restricted license which does not cover "commercial" usage in any way. ETHZ and UZH talked to Oracle and got the answer that any usage of Java at these institution is commercial.
Due to some other changes in Java functionality you need Java version 1.8 for the use with B-Fabric Download Manager. Lower or higher versions do not work.

OpenJDK

Download

OpenJDK is a free (GPL) version of Java which can be used unrestricted.
Make sure to download Java version 1.8.0.XXX.

Install

Follow the screenshots below for installation.
It is crucial, that you activate the Web Start, which is not installed by default.

Screenshots

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B-Fabric Download Manager

After installation of Java you can use the B-Fabric Download Manager to download many files in one step.
Click on any button in B-Fabric with the name "Download" to start.
See the screenshots below.

Screenshots

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