Hi need help creating a CarFactory Queue Program in JAVA

Cannot use ArrayList or java.util package

A factory creates 3 signature cars

Every 20 seconds an order enters for any of the 3 iconic cars at random.

Orders are prepared in the order of entry.

During 8 minutes, the largest number of emblem cars must be created.

Cannot use ArrayList or java.util package

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Car types

- Sports Car // Attributes: Special Engine - BodyCar

- Truck // Load Engine - BodyCar

- Machinery // Load Engine - Special BodyCar - Special Wheels

Cannot use ArrayList or java.util package

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Car building:

 It takes 6 workers or 3 robots to build a car.  You must select the materials that appear on the conveyor belt.  A maximum of 3 cars can be built at a time.  Robots build twice as fast as workers.

Cannot use ArrayList or java.util package

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Conveyor Belt: 

 You can have up to 6 materials on the tape.  Materials are generated randomly.  When the converyor belt has less than 3 materials, new materials must be added randomly to complete the 6 materials.  You must have a garbage can in case the available material is not used to build a car.

Cannot use ArrayList or java.util package

This is for as Data Structure course, so it has to use queue/stacks/nodes etc.

Thanks!