以前空闲的时候用C#实现的路径规划算法,今日贴它出来,看大家有没有更好的实现方案。关于路径规划(最短路径)算法的背景知识,大家可以参考《C++算法--图算法》一书。
该图算法描述的是这样的场景:图由节点和带有方向的边构成,每条边都有相应的权值,路径规划(最短路径)算法就是要找出从节点A到节点B的累积权值最小的路径。
首先,我们可以将“有向边”抽象为Edge类:
在计算的过程中,我们需要记录到达每一个节点权值最小的路径,这个抽象可以用PassedPath类来表示:
另外,还需要一个表PlanCourse来记录规划的中间结果,即它管理了每一个节点的PassedPath。
/// <summary>
/// PlanCourse 缓存从源节点到其它任一节点的最小权值路径=》路径表
/// </summary>
public class PlanCourse
{
private Hashtable htPassedPath ;
#region ctor
public PlanCourse(ArrayList nodeList ,string originID)
{
this.htPassedPath = new Hashtable() ;
Node originNode = null ;
foreach(Node node in nodeList)
{
if(node.ID == originID)
{
originNode = node ;
}
else
{
PassedPath pPath = new PassedPath(node.ID) ;
this.htPassedPath.Add(node.ID ,pPath) ;
}
}
if(originNode == null)
{
throw new Exception("The origin node is not exist !") ;
}
this.InitializeWeight(originNode) ;
}
private void InitializeWeight(Node originNode)
{
if((originNode.EdgeList == null) ||(originNode.EdgeList.Count == 0))
{
return ;
}
foreach(Edge edge in originNode.EdgeList)
{
PassedPath pPath = this[edge.EndNodeID] ;
if(pPath == null)
{
continue ;
}
pPath.PassedIDList.Add(originNode.ID) ;
pPath.Weight = edge.Weight ;
}
}
#endregion
public PassedPath this[string nodeID]
{
get
{
return (PassedPath)this.htPassedPath[nodeID] ;
}
}
}
在所有的基础构建好后,路径规划算法就很容易实施了,该算法主要步骤如下:
(1)用一张表(PlanCourse)记录源点到任何其它一节点的最小权值,初始化这张表时,如果源点能直通某节点,则权值设为对应的边的权,否则设为double.MaxValue。
(2)选取没有被处理并且当前累积权值最小的节点TargetNode,用其边的可达性来更新到达其它节点的路径和权值(如果其它节点 经此节点后权值变小则更新,否则不更新),然后标记TargetNode为已处理。
(3)重复(2),直至所有的可达节点都被处理一遍。
(4)从PlanCourse表中获取目的点的PassedPath,即为结果。
下面就来看上述步骤的实现,该实现被封装在RoutePlanner类中:
该图算法描述的是这样的场景:图由节点和带有方向的边构成,每条边都有相应的权值,路径规划(最短路径)算法就是要找出从节点A到节点B的累积权值最小的路径。
首先,我们可以将“有向边”抽象为Edge类:
public class Edge
{
public string StartNodeID ;
public string EndNodeID ;
public double Weight ; //权值,代价
}
节点则抽象成Node类,一个节点上挂着以此节点作为起点的“出边”表。{
public string StartNodeID ;
public string EndNodeID ;
public double Weight ; //权值,代价
}
public class Node
{
private string iD ;
private ArrayList edgeList ;//Edge的集合--出边表
public Node(string id )
{
this.iD = id ;
this.edgeList = new ArrayList() ;
}
property
}
{
private string iD ;
private ArrayList edgeList ;//Edge的集合--出边表
public Node(string id )
{
this.iD = id ;
this.edgeList = new ArrayList() ;
}
property
}
在计算的过程中,我们需要记录到达每一个节点权值最小的路径,这个抽象可以用PassedPath类来表示:
/// <summary>
/// PassedPath 用于缓存计算过程中的到达某个节点的权值最小的路径
/// </summary>
public class PassedPath
{
private string curNodeID ;
private bool beProcessed ; //是否已被处理
private double weight ; //累积的权值
private ArrayList passedIDList ; //路径
public PassedPath(string ID)
{
this.curNodeID = ID ;
this.weight = double.MaxValue ;
this.passedIDList = new ArrayList() ;
this.beProcessed = false ;
}
#region property
public bool BeProcessed
{
get
{
return this.beProcessed ;
}
set
{
this.beProcessed = value ;
}
}
public string CurNodeID
{
get
{
return this.curNodeID ;
}
}
public double Weight
{
get
{
return this.weight ;
}
set
{
this.weight = value ;
}
}
public ArrayList PassedIDList
{
get
{
return this.passedIDList ;
}
}
#endregion
}
/// PassedPath 用于缓存计算过程中的到达某个节点的权值最小的路径
/// </summary>
public class PassedPath
{
private string curNodeID ;
private bool beProcessed ; //是否已被处理
private double weight ; //累积的权值
private ArrayList passedIDList ; //路径
public PassedPath(string ID)
{
this.curNodeID = ID ;
this.weight = double.MaxValue ;
this.passedIDList = new ArrayList() ;
this.beProcessed = false ;
}
#region property
public bool BeProcessed
{
get
{
return this.beProcessed ;
}
set
{
this.beProcessed = value ;
}
}
public string CurNodeID
{
get
{
return this.curNodeID ;
}
}
public double Weight
{
get
{
return this.weight ;
}
set
{
this.weight = value ;
}
}
public ArrayList PassedIDList
{
get
{
return this.passedIDList ;
}
}
#endregion
}
另外,还需要一个表PlanCourse来记录规划的中间结果,即它管理了每一个节点的PassedPath。
/// <summary>
/// PlanCourse 缓存从源节点到其它任一节点的最小权值路径=》路径表
/// </summary>
public class PlanCourse
{
private Hashtable htPassedPath ;
#region ctor
public PlanCourse(ArrayList nodeList ,string originID)
{
this.htPassedPath = new Hashtable() ;
Node originNode = null ;
foreach(Node node in nodeList)
{
if(node.ID == originID)
{
originNode = node ;
}
else
{
PassedPath pPath = new PassedPath(node.ID) ;
this.htPassedPath.Add(node.ID ,pPath) ;
}
}
if(originNode == null)
{
throw new Exception("The origin node is not exist !") ;
}
this.InitializeWeight(originNode) ;
}
private void InitializeWeight(Node originNode)
{
if((originNode.EdgeList == null) ||(originNode.EdgeList.Count == 0))
{
return ;
}
foreach(Edge edge in originNode.EdgeList)
{
PassedPath pPath = this[edge.EndNodeID] ;
if(pPath == null)
{
continue ;
}
pPath.PassedIDList.Add(originNode.ID) ;
pPath.Weight = edge.Weight ;
}
}
#endregion
public PassedPath this[string nodeID]
{
get
{
return (PassedPath)this.htPassedPath[nodeID] ;
}
}
}
在所有的基础构建好后,路径规划算法就很容易实施了,该算法主要步骤如下:
(1)用一张表(PlanCourse)记录源点到任何其它一节点的最小权值,初始化这张表时,如果源点能直通某节点,则权值设为对应的边的权,否则设为double.MaxValue。
(2)选取没有被处理并且当前累积权值最小的节点TargetNode,用其边的可达性来更新到达其它节点的路径和权值(如果其它节点 经此节点后权值变小则更新,否则不更新),然后标记TargetNode为已处理。
(3)重复(2),直至所有的可达节点都被处理一遍。
(4)从PlanCourse表中获取目的点的PassedPath,即为结果。
下面就来看上述步骤的实现,该实现被封装在RoutePlanner类中:
/// <summary>
/// RoutePlanner 提供图算法中常用的路径规划功能。
/// 2005.09.06
/// </summary>
public class RoutePlanner
{
public RoutePlanner()
{
}
#region Paln
//获取权值最小的路径
public RoutePlanResult Paln(ArrayList nodeList ,string originID ,string destID)
{
PlanCourse planCourse = new PlanCourse(nodeList ,originID) ;
Node curNode = this.GetMinWeightRudeNode(planCourse ,nodeList ,originID) ;
#region 计算过程
while(curNode != null)
{
PassedPath curPath = planCourse[curNode.ID] ;
foreach(Edge edge in curNode.EdgeList)
{
PassedPath targetPath = planCourse[edge.EndNodeID] ;
double tempWeight = curPath.Weight + edge.Weight ;
if(tempWeight < targetPath.Weight)
{
targetPath.Weight = tempWeight ;
targetPath.PassedIDList.Clear() ;
for(int i=0 ;i<curPath.PassedIDList.Count ;i++)
{
targetPath.PassedIDList.Add(curPath.PassedIDList[i].ToString()) ;
}
targetPath.PassedIDList.Add(curNode.ID) ;
}
}
//标志为已处理
planCourse[curNode.ID].BeProcessed = true ;
//获取下一个未处理节点
curNode = this.GetMinWeightRudeNode(planCourse ,nodeList ,originID) ;
}
#endregion
//表示规划结束
return this.GetResult(planCourse ,destID) ;
}
#endregion
#region private method
#region GetResult
//从PlanCourse表中取出目标节点的PassedPath,这个PassedPath即是规划结果
private RoutePlanResult GetResult(PlanCourse planCourse ,string destID)
{
PassedPath pPath = planCourse[destID] ;
if(pPath.Weight == int.MaxValue)
{
RoutePlanResult result1 = new RoutePlanResult(null ,int.MaxValue) ;
return result1 ;
}
string[] passedNodeIDs = new string[pPath.PassedIDList.Count] ;
for(int i=0 ;i<passedNodeIDs.Length ;i++)
{
passedNodeIDs[i] = pPath.PassedIDList[i].ToString() ;
}
RoutePlanResult result = new RoutePlanResult(passedNodeIDs ,pPath.Weight) ;
return result ;
}
#endregion
#region GetMinWeightRudeNode
//从PlanCourse取出一个当前累积权值最小,并且没有被处理过的节点
private Node GetMinWeightRudeNode(PlanCourse planCourse ,ArrayList nodeList ,string originID)
{
double weight = double.MaxValue ;
Node destNode = null ;
foreach(Node node in nodeList)
{
if(node.ID == originID)
{
continue ;
}
PassedPath pPath = planCourse[node.ID] ;
if(pPath.BeProcessed)
{
continue ;
}
if(pPath.Weight < weight)
{
weight = pPath.Weight ;
destNode = node ;
}
}
return destNode ;
}
#endregion
#endregion
}
/// RoutePlanner 提供图算法中常用的路径规划功能。
/// 2005.09.06
/// </summary>
public class RoutePlanner
{
public RoutePlanner()
{
}
#region Paln
//获取权值最小的路径
public RoutePlanResult Paln(ArrayList nodeList ,string originID ,string destID)
{
PlanCourse planCourse = new PlanCourse(nodeList ,originID) ;
Node curNode = this.GetMinWeightRudeNode(planCourse ,nodeList ,originID) ;
#region 计算过程
while(curNode != null)
{
PassedPath curPath = planCourse[curNode.ID] ;
foreach(Edge edge in curNode.EdgeList)
{
PassedPath targetPath = planCourse[edge.EndNodeID] ;
double tempWeight = curPath.Weight + edge.Weight ;
if(tempWeight < targetPath.Weight)
{
targetPath.Weight = tempWeight ;
targetPath.PassedIDList.Clear() ;
for(int i=0 ;i<curPath.PassedIDList.Count ;i++)
{
targetPath.PassedIDList.Add(curPath.PassedIDList[i].ToString()) ;
}
targetPath.PassedIDList.Add(curNode.ID) ;
}
}
//标志为已处理
planCourse[curNode.ID].BeProcessed = true ;
//获取下一个未处理节点
curNode = this.GetMinWeightRudeNode(planCourse ,nodeList ,originID) ;
}
#endregion
//表示规划结束
return this.GetResult(planCourse ,destID) ;
}
#endregion
#region private method
#region GetResult
//从PlanCourse表中取出目标节点的PassedPath,这个PassedPath即是规划结果
private RoutePlanResult GetResult(PlanCourse planCourse ,string destID)
{
PassedPath pPath = planCourse[destID] ;
if(pPath.Weight == int.MaxValue)
{
RoutePlanResult result1 = new RoutePlanResult(null ,int.MaxValue) ;
return result1 ;
}
string[] passedNodeIDs = new string[pPath.PassedIDList.Count] ;
for(int i=0 ;i<passedNodeIDs.Length ;i++)
{
passedNodeIDs[i] = pPath.PassedIDList[i].ToString() ;
}
RoutePlanResult result = new RoutePlanResult(passedNodeIDs ,pPath.Weight) ;
return result ;
}
#endregion
#region GetMinWeightRudeNode
//从PlanCourse取出一个当前累积权值最小,并且没有被处理过的节点
private Node GetMinWeightRudeNode(PlanCourse planCourse ,ArrayList nodeList ,string originID)
{
double weight = double.MaxValue ;
Node destNode = null ;
foreach(Node node in nodeList)
{
if(node.ID == originID)
{
continue ;
}
PassedPath pPath = planCourse[node.ID] ;
if(pPath.BeProcessed)
{
continue ;
}
if(pPath.Weight < weight)
{
weight = pPath.Weight ;
destNode = node ;
}
}
return destNode ;
}
#endregion
#endregion
}
Feedback
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
/**
* @author 周振興
* @version 1.00
*/
public class Edge {
public String StartNodeID;
public String EndNodeID;
public double Weight;
/**
* @return Returns the endNodeID.
*/
public String getEndNodeID() {
return EndNodeID;
}
/**
* @param endNodeID The endNodeID to set.
*/
public void setEndNodeID(String endNodeID) {
EndNodeID = endNodeID;
}
/**
* @return Returns the startNodeID.
*/
public String getStartNodeID() {
return StartNodeID;
}
/**
* @param startNodeID The startNodeID to set.
*/
public void setStartNodeID(String startNodeID) {
StartNodeID = startNodeID;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return Weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
Weight = weight;
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
/**
* @author 周振興
* @version 1.00
*/
public class Edge {
public String StartNodeID;
public String EndNodeID;
public double Weight;
/**
* @return Returns the endNodeID.
*/
public String getEndNodeID() {
return EndNodeID;
}
/**
* @param endNodeID The endNodeID to set.
*/
public void setEndNodeID(String endNodeID) {
EndNodeID = endNodeID;
}
/**
* @return Returns the startNodeID.
*/
public String getStartNodeID() {
return StartNodeID;
}
/**
* @param startNodeID The startNodeID to set.
*/
public void setStartNodeID(String startNodeID) {
StartNodeID = startNodeID;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return Weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
Weight = weight;
}
}
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class Node {
private String iD;
private ArrayList edgeList;
public Node(String id) {
this.iD = id;
this.edgeList = new ArrayList();
}
/**
* @return Returns the edgeList.
*/
public ArrayList getEdgeList() {
return edgeList;
}
/**
* @param edgeList The edgeList to set.
*/
public void setEdgeList(ArrayList edgeList) {
this.edgeList = edgeList;
}
/**
* @return Returns the iD.
*/
public String getID() {
return iD;
}
/**
* @param id The iD to set.
*/
public void setID(String id) {
iD = id;
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class Node {
private String iD;
private ArrayList edgeList;
public Node(String id) {
this.iD = id;
this.edgeList = new ArrayList();
}
/**
* @return Returns the edgeList.
*/
public ArrayList getEdgeList() {
return edgeList;
}
/**
* @param edgeList The edgeList to set.
*/
public void setEdgeList(ArrayList edgeList) {
this.edgeList = edgeList;
}
/**
* @return Returns the iD.
*/
public String getID() {
return iD;
}
/**
* @param id The iD to set.
*/
public void setID(String id) {
iD = id;
}
}
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class PassedPath {
private String curNodeID;
private boolean beProcessed;
private double weight;
private ArrayList passedIDList;
public PassedPath(String ID) {
this.curNodeID = ID;
this.weight = Double.MAX_VALUE;
this.passedIDList = new ArrayList();
this.beProcessed = false;
}
/**
* @return Returns the beProcessed.
*/
public boolean isBeProcessed() {
return beProcessed;
}
/**
* @param beProcessed The beProcessed to set.
*/
public void setBeProcessed(boolean beProcessed) {
this.beProcessed = beProcessed;
}
/**
* @return Returns the curNodeID.
*/
public String getCurNodeID() {
return curNodeID;
}
/**
* @param curNodeID The curNodeID to set.
*/
public void setCurNodeID(String curNodeID) {
this.curNodeID = curNodeID;
}
/**
* @return Returns the passedIDList.
*/
public ArrayList getPassedIDList() {
return passedIDList;
}
/**
* @param passedIDList The passedIDList to set.
*/
public void setPassedIDList(ArrayList passedIDList) {
this.passedIDList = passedIDList;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
this.weight = weight;
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class PassedPath {
private String curNodeID;
private boolean beProcessed;
private double weight;
private ArrayList passedIDList;
public PassedPath(String ID) {
this.curNodeID = ID;
this.weight = Double.MAX_VALUE;
this.passedIDList = new ArrayList();
this.beProcessed = false;
}
/**
* @return Returns the beProcessed.
*/
public boolean isBeProcessed() {
return beProcessed;
}
/**
* @param beProcessed The beProcessed to set.
*/
public void setBeProcessed(boolean beProcessed) {
this.beProcessed = beProcessed;
}
/**
* @return Returns the curNodeID.
*/
public String getCurNodeID() {
return curNodeID;
}
/**
* @param curNodeID The curNodeID to set.
*/
public void setCurNodeID(String curNodeID) {
this.curNodeID = curNodeID;
}
/**
* @return Returns the passedIDList.
*/
public ArrayList getPassedIDList() {
return passedIDList;
}
/**
* @param passedIDList The passedIDList to set.
*/
public void setPassedIDList(ArrayList passedIDList) {
this.passedIDList = passedIDList;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
this.weight = weight;
}
}
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
import java.util.Hashtable;
/**
* @author 周振興
* @version 1.00
*/
public class PlanCourse {
private Hashtable htPassedPath;
public PlanCourse(ArrayList nodeList, String originID) throws Exception {
this.htPassedPath = new Hashtable();
Node originNode = null;
for (int i = 0; i < nodeList.size(); i++) {
Node node = (Node) nodeList.get(i);
if (node.getID() == originID) {
originNode = node;
} else {
PassedPath pPath = new PassedPath(node.getID());
this.htPassedPath.put(node.getID(), pPath);
}
}
if (originNode == null) {
throw new Exception("The origin node is not exist !");
}
this.InitializeWeight(originNode);
}
private void InitializeWeight(Node originNode) {
if ((originNode.getEdgeList() == null) || (originNode.getEdgeList().size() == 0)) {
return;
}
for (int i = 0; i < originNode.getEdgeList().size(); i++) {
Edge edge = (Edge) originNode.getEdgeList().get(i);
PassedPath pPath = getPassedPath(edge.EndNodeID);
if (pPath == null) {
continue;
}
pPath.getPassedIDList().add(originNode.getID());
pPath.setWeight(edge.getWeight());
}
}
public PassedPath getPassedPath(String nodeID) {
return (PassedPath) this.htPassedPath.get(nodeID);
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
import java.util.Hashtable;
/**
* @author 周振興
* @version 1.00
*/
public class PlanCourse {
private Hashtable htPassedPath;
public PlanCourse(ArrayList nodeList, String originID) throws Exception {
this.htPassedPath = new Hashtable();
Node originNode = null;
for (int i = 0; i < nodeList.size(); i++) {
Node node = (Node) nodeList.get(i);
if (node.getID() == originID) {
originNode = node;
} else {
PassedPath pPath = new PassedPath(node.getID());
this.htPassedPath.put(node.getID(), pPath);
}
}
if (originNode == null) {
throw new Exception("The origin node is not exist !");
}
this.InitializeWeight(originNode);
}
private void InitializeWeight(Node originNode) {
if ((originNode.getEdgeList() == null) || (originNode.getEdgeList().size() == 0)) {
return;
}
for (int i = 0; i < originNode.getEdgeList().size(); i++) {
Edge edge = (Edge) originNode.getEdgeList().get(i);
PassedPath pPath = getPassedPath(edge.EndNodeID);
if (pPath == null) {
continue;
}
pPath.getPassedIDList().add(originNode.getID());
pPath.setWeight(edge.getWeight());
}
}
public PassedPath getPassedPath(String nodeID) {
return (PassedPath) this.htPassedPath.get(nodeID);
}
}
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class RoutePlanner {
public RoutePlanner() {
}
public RoutePlanResult Paln(ArrayList nodeList, String originID, String destID) throws Exception {
PlanCourse planCourse = new PlanCourse(nodeList, originID);
Node curNode = this.GetMinWeightRudeNode(planCourse, nodeList, originID);
while (curNode != null) {
PassedPath curPath = planCourse.getPassedPath(curNode.getID());
for (int j = 0; j < curNode.getEdgeList().size(); j++) {
Edge edge = (Edge) curNode.getEdgeList().get(j);
PassedPath targetPath = planCourse.getPassedPath(edge.EndNodeID);
double tempWeight = curPath.getWeight() + edge.getWeight();
if (tempWeight < targetPath.getWeight()) {
targetPath.setWeight(tempWeight);
targetPath.getPassedIDList().clear();
for (int i = 0; i < curPath.getPassedIDList().size(); i++) {
targetPath.getPassedIDList().add(curPath.getPassedIDList().get(i).toString());
}
targetPath.getPassedIDList().add(curNode.getID());
}
}
planCourse.getPassedPath(curNode.getID()).setBeProcessed(true);
curNode = this.GetMinWeightRudeNode(planCourse, nodeList, originID);
}
return this.GetResult(planCourse, destID);
}
private RoutePlanResult GetResult(PlanCourse planCourse, String destID) {
PassedPath pPath = planCourse.getPassedPath(destID);
if (pPath.getWeight() == Integer.MAX_VALUE) {
RoutePlanResult result1 = new RoutePlanResult(null, Integer.MAX_VALUE);
return result1;
}
String[] passedNodeIDs = new String[pPath.getPassedIDList().size()];
for (int i = 0; i < passedNodeIDs.length; i++) {
passedNodeIDs[i] = pPath.getPassedIDList().get(i).toString();
}
RoutePlanResult result = new RoutePlanResult(passedNodeIDs, pPath.getWeight());
return result;
}
private Node GetMinWeightRudeNode(PlanCourse planCourse, ArrayList nodeList, String originID) {
double weight = Double.MAX_VALUE;
Node destNode = null;
for (int i = 0; i < nodeList.size(); i++) {
Node node = (Node) nodeList.get(i);
if (node.getID() == originID) {
continue;
}
PassedPath pPath = planCourse.getPassedPath(node.getID());
if (pPath.isBeProcessed()) {
continue;
}
if (pPath.getWeight() < weight) {
weight = pPath.getWeight();
destNode = node;
}
}
return destNode;
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
import java.util.ArrayList;
/**
* @author 周振興
* @version 1.00
*/
public class RoutePlanner {
public RoutePlanner() {
}
public RoutePlanResult Paln(ArrayList nodeList, String originID, String destID) throws Exception {
PlanCourse planCourse = new PlanCourse(nodeList, originID);
Node curNode = this.GetMinWeightRudeNode(planCourse, nodeList, originID);
while (curNode != null) {
PassedPath curPath = planCourse.getPassedPath(curNode.getID());
for (int j = 0; j < curNode.getEdgeList().size(); j++) {
Edge edge = (Edge) curNode.getEdgeList().get(j);
PassedPath targetPath = planCourse.getPassedPath(edge.EndNodeID);
double tempWeight = curPath.getWeight() + edge.getWeight();
if (tempWeight < targetPath.getWeight()) {
targetPath.setWeight(tempWeight);
targetPath.getPassedIDList().clear();
for (int i = 0; i < curPath.getPassedIDList().size(); i++) {
targetPath.getPassedIDList().add(curPath.getPassedIDList().get(i).toString());
}
targetPath.getPassedIDList().add(curNode.getID());
}
}
planCourse.getPassedPath(curNode.getID()).setBeProcessed(true);
curNode = this.GetMinWeightRudeNode(planCourse, nodeList, originID);
}
return this.GetResult(planCourse, destID);
}
private RoutePlanResult GetResult(PlanCourse planCourse, String destID) {
PassedPath pPath = planCourse.getPassedPath(destID);
if (pPath.getWeight() == Integer.MAX_VALUE) {
RoutePlanResult result1 = new RoutePlanResult(null, Integer.MAX_VALUE);
return result1;
}
String[] passedNodeIDs = new String[pPath.getPassedIDList().size()];
for (int i = 0; i < passedNodeIDs.length; i++) {
passedNodeIDs[i] = pPath.getPassedIDList().get(i).toString();
}
RoutePlanResult result = new RoutePlanResult(passedNodeIDs, pPath.getWeight());
return result;
}
private Node GetMinWeightRudeNode(PlanCourse planCourse, ArrayList nodeList, String originID) {
double weight = Double.MAX_VALUE;
Node destNode = null;
for (int i = 0; i < nodeList.size(); i++) {
Node node = (Node) nodeList.get(i);
if (node.getID() == originID) {
continue;
}
PassedPath pPath = planCourse.getPassedPath(node.getID());
if (pPath.isBeProcessed()) {
continue;
}
if (pPath.getWeight() < weight) {
weight = pPath.getWeight();
destNode = node;
}
}
return destNode;
}
}
//==========================================================================
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
/**
* @author 周振興
* @version 1.00
*/
public class RoutePlanResult {
private String[] passedNodeIDs;
private double weight;
public RoutePlanResult(String[] strings, double d) {
this.passedNodeIDs = strings;
this.weight = d;
}
/**
* @return Returns the passedNodeIDs.
*/
public String[] getPassedNodeIDs() {
return passedNodeIDs;
}
/**
* @param passedNodeIDs The passedNodeIDs to set.
*/
public void setPassedNodeIDs(String[] passedNodeIDs) {
this.passedNodeIDs = passedNodeIDs;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
this.weight = weight;
}
}
// version 変更日 変更者 変更内容
//--------------------------------------------------------------------------
// 1.00 2006/01/31 周振興 新規作成
//**************************************************************************
package path;
/**
* @author 周振興
* @version 1.00
*/
public class RoutePlanResult {
private String[] passedNodeIDs;
private double weight;
public RoutePlanResult(String[] strings, double d) {
this.passedNodeIDs = strings;
this.weight = d;
}
/**
* @return Returns the passedNodeIDs.
*/
public String[] getPassedNodeIDs() {
return passedNodeIDs;
}
/**
* @param passedNodeIDs The passedNodeIDs to set.
*/
public void setPassedNodeIDs(String[] passedNodeIDs) {
this.passedNodeIDs = passedNodeIDs;
}
/**
* @return Returns the weight.
*/
public double getWeight() {
return weight;
}
/**
* @param weight The weight to set.
*/
public void setWeight(double weight) {
this.weight = weight;
}
}