Write an implementation for abstract data type “Bag” as a Java class, which is likea Set, but it may contain several instances of the same member. For example, {'to', 'be', 'or', 'not', 'to', 'be'} is a bag of words, which is equal to {'be', 'be', 'not', 'or', 'to', 'to'} (since order of members is insignificant), but is unequal to {'be', 'not', 'or', 'to'} (since the number of instances is significant). Adding a member increases the number of instances in the bag by one and removing a member decreases the number of instances in the bag by one. The member is deleted from the bag when it has no instances.
Think that “how would you represent a bag without actually storing multiple instances of the same member?” Your implementations should be efficientas possible.
Don’t forget that you cannot use any pre-written Java API Class! You should write your own code for data structures. You are allowed to use lab source codes that we examined so far, however it is preferableto write your own codes for yourdata structure.
our implementation must be generic, i.e. your bag can accept any type of instances. (Use Java Generics!)
Your ADT should provide at least these operations (you can add other “public” or “private” methods you want):
- add(AnyTypeitem): Inserts item in the bag.
- clear(): Removes all of the elements from this bag.
- contains(AnyTypeitem): Returns true if this bag contains the specified element and false otherwise.-
- distictSize(): Returns the distinct number of elements in this bag. (For example, for the bag {'to', 'be', 'or', 'not', 'to', 'be'} distinctsize is 4)
- equals(Object obj): Indicates whether some bag object is "equal to" this one. (Returns “true” or “false”)
- elementSize(AnyTypeitem): Returns the number of this item in this bag. (For example, for the bag {'to', 'be', 'or', 'not', 'to', 'be'} elementsize(‘be’) is 2)
- isEmpty(): Returns true if this collection contains no elements.
- remove(AnyTypeitem): Removes a single instance of item from this bag and returns true if it is present; otherwise returns false.
- size(): Returns the total number of elements in this bag.(For example, for the bag{'to', 'be', 'or', 'not', 'to', 'be'} size is 6)
- toString(): Returns a string that displays the elements in the bag. (The style to be used is up to your preference.)
Please also write a Test program (a separate Java class) proves that your container(bag) works properly.