Provide an explanation and java code for your solution.

Let T be a given binary tree with n nodes. The distance between two nodes p and q in T is the number of edges along the unique simple path between p and q,ie, dp+ dq-2da, where a is the lowest common ancestor (LCA) of p and q, and dx denotes the depth of node x in T. The diameter of T is the maximum distance between two nodes in T i.e., the distance between the farthest pair of nodes in T). Give an efficient algorithm for computing the diameter of T and analyze its running time. Note: Each node of T stores an element and a pair of references to its left and right children. Other than that, nodes of T do not have any additional space to store extra information, not even their depths. Also, you should not attempt to create a clone of T with extra spaces in the clone nodes. Hint: use a post-order traversal of T with strengthened post-condition. As an example, see how we use a composite Result type as the return type in the EulerTour algorithm, LS8, pp: 20-21.]