This assignment is about experimenting with the Java runtime system's garbage collection model, and comparing it with the C++ manual memory allocation model. Below is the Garbage Java class/program that creates Chair objects and counts the number of objects having been created. The Chair class defines a finalize method that is called when the Chair objects are garbage collected.
After having created the objects, the Garbage program has three options, triggered by command-line arguments: (1) "before": calls the garbage collector manually, then runs finalization methods, (2) "after": instructs the garbage collector to run all finalization methods without explicitly calling for garbage collection to occur, and finally (3) if no command line arguments are provided, the normal garbage collection procedure occurs, without any explicit call directing how it should proceed.
Part 1:
Run the Garbage program and observe how it behaves using each of the three cases described above. Explain the results in terms of how the garbage collection system is behaving in each case.
Part 2:
Write a similar program in C++ using pointers to Chair objects, where the implementation behaviour of the finalize method is put into a destructor. Explain what happens when all the objects are explicitly deleted, and when they are not. Explain the differences with some of the results you got in part 1.
Part 3:
Re-write the program written in part 2, this time using STL C++ auto_ptr pointers to Chair objects and do the same experimentation. Explain your results compared to the results you got in parts 1 and 2.