Please do this and explain in Java:

Backtracking is an algorithmic technique to solve problems recursively by exploring every possible valid choice. During the process, it will remove solutions that fail to satisfy the constraints of the problem, and once it hits the final state, it will add the working solution to the final result. Problems like 8-Queens, Sudoku, permutations in letters, and combinations in digits can be solved by using backtracking. Given an array of distinct integer and an integer target , find all the unique combinations of where the chosen numbers sum to the , the order of the combinations can be vary. Rules: - Each combination must be unique: the frequency of at least of the chosen number is different - You may choose the same number from the array unlimited times Notes: - You don't need to handle any exceptions in your code, the test cases will follow rules of the Constraints, there're no tricks - The size of the array: - The range of each integer in the array: - All elements are distinct in the given array - 1 Examples Input: numbers =[2,3,4,6], target =6 Output: [[2,2,2],[2,4],[3,3],[6]] Explanation: 2+2+2=6(Notethat2usedmultipletimes)2+4=63+3=66=6 Input: numbers =[2,3,4,6], target =12 Output: [[2,2,2,2,2,2],[2,2,2,2,4],[2,2,2,3,3],[2,2,2,6],[2,2,4,4],[2,3,3,4],[2,6,4],[3,3, 3,3],[3,3,6],[6,6],[4,4,4]] Input: numbers =[2], target =1 Output: [] Explanation: No macthed number sum up to 1 Requirements - You must submit a single Java file containing the class named Lab02. Your class must contain the function named "findCombinations" with the following headers: public static List (