Use java programming for the following questions to have the solutions ready within today Jan 3 2020 at or before 7:00PM GMT+8 time zone:

Write a method recursive(char aa, char bb) of a class Chart which returns a string starting from aa, concatenating with characters having values aa+1, aa+2, ... and ending with bb using recursion, where aa <= bb. For example, the call aChart.recursive('b', 'e') returns the string:

bcde

where aChart is an object of the class Chart.