Please give java code for the below and provide detailed comments and pseudocode for each step and on efficiency - Please also make use of advanced approaches such as recursion, and demonstrating a more efficient approach.

With the aid of a full code implementation, show how you can take an array of n values, determine how many unique elements e are part of the array and output each unique value once in ascending order. For the case of the above example, the value n would be 6 , the number of unique value elements e would be 5 , and those unique values would be outputted as: 1,2,6,8,9