Guid.rar_out_游览图

package xiang; import java.io.IOException; import java.util.*; /** * class Visit 用来处理人机交互的命令 * */ public class Visit { protected Spot location;// 当前所在地点 protected Building bd = new Building(); /* 地点描述 Key是地点描述description 以及地点 Value是地点Spot之间的映射Map */ private Map spotDescriptonMap = new HashMap(); final static int where = 0;// 显示当前在什么地方 final static int list = 1;// 列出当前位置附近的地点或者物品 final static int gotos = 2;// 到另一个地点 final static int look = 3;// 查询某个物品是否在当前地点 final static int help = 4;// 命令行提示，列出各种命令 public Visit() { location = bd.getSpots()[0];// 当前位置 mapSpotDescriptioToSpot(); } /** * 实现 spotDescriptio到spot的映射 * * @param sp * 代表地点数组 */ private void mapSpotDescriptioToSpot() { Spot[] sp = bd.getSpots(); int n = sp.length; for (int i = 0; i < n; i++) { spotDescriptonMap.put(sp[i].description, sp[i]); } } /** * 获取人机交互的命令 * */ public String getCommand() { byte[] b = new byte[20]; String s = new String(); try { int n = System.in.read(b);// 回车换行也读到了,所以下面要减2 s = new String(b, 0, n - 2); s = s.trim(); } catch (IOException e) { e.printStackTrace(); } finally { } return s; } /** * 处理控制台输入的命令s */ public boolean processCommand(String s) { boolean bl = true; if (!(s.compareTo("") == 0)) { int n = s.indexOf(' '); if (n == -1) { if (s.compareToIgnoreCase("where") == 0) { processCommand(where); } else if (s.compareToIgnoreCase("help") == 0) { processCommand(help); } else if (s.compareToIgnoreCase("list") == 0) { processCommand(list); } else bl = false; } else { String s1 = s.substring(0, s.indexOf(' ')); String s2 = s.substring(s.indexOf(' ') + 1); s2=s2.trim(); if (s1.compareToIgnoreCase("goto") == 0) { bl = processCommand(gotos, s2); } else if (s1.compareToIgnoreCase("list") == 0) { bl = processCommand(list, s2); } else if (s1.compareToIgnoreCase("look") == 0) { bl = processCommand(look, s2); } else bl = false; } } return bl; } /** * 处理各种命令 双参数 * * @param command * 代表命令，例如look，goto,where * @param obj * 代表物品或者地点 比如 电脑,电视，登记表 */ private boolean processCommand(int command, String obj) { if (command == gotos) { /* 不包含这个地点 */ if (!spotDescriptonMap.containsKey(obj)) System.out.println(obj + " is not in the building"); else { Spot sp = (Spot) spotDescriptonMap.get(obj);// 类型转换 /* 原地 */ if (sp == location) System.out.println("You are at " + location.description + " now."); /* 不能直接到这个地点，当前位置与obj不相邻 */ else if (!location.adjacentList.contains(sp)) processGotoCommand(sp); /* 当前位置移到obj */ else { System.out.println(obj); location = sp; } } } if (command == list) return processListCommand(obj); /* 当前地点有没有obj这个物品 */ else if (command == look) { if (!location.goodsList.contains(obj)) { System.out.println(obj + " is not at " + location.description); } else { System.out.println(obj + " is at " + location.description); } } return true; } /** * 到一个不相邻的地点 * * @param sp * 要去的地点 */ private void processGotoCommand(Spot sp) { int n = bd.getSpotNumber(); float[][] cost = bd.getDistance();/* 相邻地点之间的距离 */ float[] dist = new float[n];/* 到obj的距离 */ int[][] path = new int[n][n];/* 到obj的路径 */ Spot[] spots = bd.getSpots();/* 获取所有地点 */ int v = location.id;/* 当前地点的编号 */ int w = sp.id;/* obj的编号 */ shortestPath(cost, v, n, dist, path); float distance = dist[w]; if (distance == Building.NOTAdjacent) {/* 不可达 */ System.out.println(sp.description + " cannot be reached from " + location.description); } else { int length = 0;/* 从v到w中间经历地点个数 */ while (path[w][length] != -1) length++; int i = 0; for (i = 0; i < length - 1; i++) { System.out.print(spots[path[w][i]].description + "->"); } System.out.println(spots[path[w][i]].description); location = spots[path[w][i]]; } } /** * * @param obj * goods spots allspots * @return 参数是否合适 */ private boolean processListCommand(String obj) { /* 列出当地物品 */ if (obj.compareToIgnoreCase("goods") == 0) { Iterator itr = location.goodsList.iterator(); while (itr.hasNext()) { Object element = itr.next(); System.out.print(element + " "); } System.out.println(); return true; } /* 列出附近地点 */ else if (obj.compareToIgnoreCase("spots") == 0) { Iterator itr = location.adjacentList.iterator(); while (itr.hasNext()) { Spot element = (Spot) itr.next(); System.out.print(element.description + " "); } System.out.println(); return true; } /* 列出大厦内所有地点 */ else if (obj.compareToIgnoreCase("allspots") == 0) { Spot[] spots = bd.getSpots(); int n = spots.length; for (int i = 0; i < n; i++) { System.out.print(spots[i].description + " "); } System.out.println(); return true; } else return false; } /** * 处理各种命令 单参数 * * @param command * 代表命令，例如list,where */ private void processCommand(int command) { switch (command) { case where:/* 显示当前位置 */ System.out.println(location.description); break; case list: {/* 列出当地物品 */ Iterator itr = location.goodsList.iterator(); while (itr.hasNext()) { Object element = itr.next(); System.out.print(element + " "); } System.out.println(); break; } case help: {/* 显示帮助命令 */ processHelpCommand(); break; } default: break; } } /** * 处理help命令 * */ private void processHelpCommand() { System.out.println("where 显示当前在什么地方"); System.out.println("list 列出当前位置的物品"); System.out.println("list allspots 列出大厦内所有地点"); System.out.println("list spots 列出当前位置附近的地点"); System.out.println("list goods 列出当前位置的物品"); System.out.println("goto someplace 到另一个地点"); System.out.println("look somegoods 查询某个物品是否在当前地点"); System.out.println("help 命令行帮助"); System.out.println("exit 退出命令行"); } /** * 单源最短路径的Dijstra算法 * * @param v * 源 * @param cost * 权值 * @param n * 结点个数 * @param dist * v到各顶点的距离 * @param path * 路径 */ static void shortestPath(float[][] cost, int v, int n, float[] dist, int[][] path) { int i, w, u, count; int[] pos = new int[n]; int[] s = new int[n]; for (i = 0; i < n; i++) { s[i] = 0; dist[i] = cost[v][i]; path[i][0] = v; for (int j = 1; j < n; j++) path[i][j] = -1;/* 标记而已 */ pos[i] = 0;/* 第i条路径的位置计数器 */ } s[v] = 1; count = 1; while (count < n) { u = minDistance(s, dist); s[u] = 1; path[u][++pos[u]] = u;/* 先自加后操作 */ count++; /* 更新 dist数组 */ for (w = 0; w < n; w++) { if (s[w] == 0 && cost[u][w] < Float.MAX_VALUE && dist[u] + cost[u][w] < dist[w]) { dist[w] = dist[u] + cost[u][w]; pos[w] = pos[u];/* 拷贝 */ for (i = 0; i <= pos[u]; i++) path[w][i] = path[u][i]; } } } } /** * @return u 利用s和dist在尚未找到最短路径的顶点中确定一个与v最接近的顶点 * */ static int minDistance(int[] s, float[] dist) { float min = Float.MAX_VALUE; int n = s.length; int u = n; for (i