Iterator Training

Expand java Iterator based on Scala API.

Background

The interface Iterator<T> in java has 2 basic methods next() and hasNext()

• next() fetches the next element from the iterator throws NoSuchElementException if the iterator has none left.
• hasNext() checks if the iterator can provide more elements in other words, if next() is safe to execute.

In this exercise you are going to use those methods to implement much more complex logic.

Before you begin

mvn dependency:resolve

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Assignment

The interface RichIterator<A> extends the basic interface Iterator<A> that was described before. It is located at src/main/java/iterator/RichIterator.java. This interface has many methods that are implemented with default implementation throw new NotImplementedExpcetion();. Your job it to implement those methods.

Guideline

The methods in RichIterator<A> are divided to three levels. Easy, Hard, Very Hard. Your work process should follow the following instructions:

• Implement ALL the methods in the Easy category
• Execute the tests mvn test -Dtest="testing.levels.easy.**"
• Fix all the functions which fails (do it without reading/debugging the tests!)
• Repeat for Hard and Very Hard (notice to execute the tests according to the level)

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Extra

After finishing all the levels try to solve the Extra cases. The extra cases are functions that reminds more day-to-day code implementation. All those functions should be implemented with the functions that you implemented before for better understanding.

In class Extra which located at src/main/java/iterator/Extra provides several functions. Perform the guideline with them as well.