I need help rewriting this python code into java: # # # A-Star # This module con

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I need help rewriting this python code into java:

# # # A-Star # This module contains functions and objects reused throughout the simulation # # import sys from shapely.geometry import Polygon, LineString polygons = [] # # Action Function # def reachable_vertices_by_state(current_state, goal_state, closed_set): reachable_vertices = [] # print("Check reachable nodes from the current node: " + str(current_state)) for polygon in polygons: for vertex in polygon.exterior.coords: # if we have it, move on if vertex in reachable_vertices: continue # ignore closed nodes if vertex in closed_set: continue # let's not test ourselves if current_state == vertex: test_line_valid = False # print("Don't need to test the current state...") continue else: test_line_valid = True test_line = LineString((current_state, vertex)) # print("Testing if " + str(vertex) + " is reachable...") obstacle_names = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'] i = 0 for obstacle in polygons: if test_line.crosses(obstacle): # print("Obstacle '" + obstacle_names[i] + "' is in the way of point " + str(vertex)) test_line_valid = False break if test_line.within(obstacle): # print("Skip non-adjacent vertices on the same obstacle '" + obstacle_names[i] + "' :" + str(vertex)) test_line_valid = False break i += 1 if test_line_valid: # print(str(test_line) + " is reachable!") reachable_vertices.append(vertex) # Test for goal state line_to_goal = LineString((current_state, goal_state)) line_to_goal_blocked = False for obstacle in polygons: if line_to_goal.crosses(obstacle) or line_to_goal.within(obstacle): line_to_goal_blocked = True break if not line_to_goal_blocked: reachable_vertices.append(goal_state) return reachable_vertices def construct_best_path(came_from, current): total_path = [current] while current in came_from: current = came_from[current] total_path.append(current) total_path.reverse() return total_path def heuristic_function(state, goal): return line_length(state, goal) def line_length(node1, node2): line = LineString((node1, node2)) return line.length def run(start, goal): closed_set = [] open_set = [start] came_from = dict() g_score = {start: 0} f_score = {start: heuristic_function(start, goal)} current_state = None while len(open_set) > 0: previous_state = current_state f_score_min = float('inf') # infinity for open_state in open_set: if f_score[open_state] < f_score_min: current_state = open_state f_score_min = f_score[open_state] # if current_state is not previous_state: # print("Current State updated: " + str(current_state)) if current_state == goal: return construct_best_path(came_from, goal) open_set.remove(current_state) closed_set.append(current_state) # print(str(current_state) + " closed!") reachable_states = reachable_vertices_by_state(current_state, goal, closed_set) # print(reachable_states) # print("Current Path: " + str(construct_best_path(came_from, current_state))) # print("State g_score distance_to_state heuristic total g(n) total f(n)") for state in reachable_states: # add cost of next potential state to current cost temp_g_score = g_score[current_state] + line_length(current_state, state) heuristic = heuristic_function(state, goal) # print(str(state).ljust(12) + " " + "{0:.3f}".format(g_score[current_state]) + " " + # "{0:.3f}".format(line_length(current_state, state)) + " " + "{0:.3f}".format(heuristic) + # " " + "{0:.3f}".format(temp_g_score) + " " + "{0:.3f}".format(temp_g_score + heuristic)) if state not in open_set: open_set.append(state) elif temp_g_score >= g_score[state]: continue came_from[state] = current_state g_score[state] = temp_g_score f_score[state] = g_score[state] + heuristic return False

Explanation / Answer

public class Node{ Object data; Node next; Node(Object data, Node next){ this.data = data; this.next = next; } public Object getData(){ return data; } public void setData (Object data){ this.data = data; } public Node getNext(){ return next; } public void setNext(Node next){ this.next = next; } }

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