public Stack stack = new Stack();/*臨時(shí)保存路徑節(jié)點(diǎn)的棧*/
public ArrayList sers = new ArrayList();/*存儲(chǔ)路徑的集合*/

public class Node/*表示一個(gè)節(jié)點(diǎn)以及和這個(gè)節(jié)點(diǎn)相連的所有節(jié)點(diǎn)*/
  {
    public String name = null; 
    public ArrayList relationNodes = new ArrayList();
   
    public String getName()
    {
      return name;
    }
    
    public void setName(String name)
    {
      this.name = name;
    }
    
    public ArrayList getRelationNodes()
    {
      return relationNodes;
    }
    
    public void setRelationNodes(ArrayList relationNodes)
    {
      this.relationNodes = relationNodes;
    }
  }

public boolean isNodeInStack(Node node)/*判斷節(jié)點(diǎn)是否在棧中*/
  {
    Iterator it = stack.iterator();
    while(it.hasNext())
    {
      Node node1 = (Node)it.next();
      if(node == node1)
        return true;
    }
    return false;
  }

public void showAndSavePath ()/*此時(shí)棧中的節(jié)點(diǎn)組成一條所求路徑，轉(zhuǎn)儲(chǔ)并打印輸出*/
  {
    Object[] o = stack.toArray();
    for(int i = 0;i<o.length;i++)
    {
      System.out.print(o[i]);
    }
    sers.add(o); /*轉(zhuǎn)儲(chǔ)*/
    System.out.println("\n");
  }

/*尋找路徑的方法*/
public boolean getPaths(Node cNode, Node pNode, Node sNode, Node eNode)
/*cNode表示當(dāng)前的起始節(jié)點(diǎn)currentNode，pNode表示當(dāng)前起始節(jié)點(diǎn)的上一節(jié)點(diǎn)previousNode，sNode表示最初的起始節(jié)點(diǎn)startNode，eNode表示終點(diǎn)endNode*/
  {
    Node nNode = null;
    if(cNode != null && pNode != null && cNode == pNode)
      return false;/*如果符合條件判斷說明出現(xiàn)環(huán)路，不能再順著該路徑繼續(xù)尋路，返回false*/
    if(cNode != null)
    {
      int i = 0;
      stack.push(cNode);/*起始節(jié)點(diǎn)入棧*/
      if(cNode == eNode)/*如果該起始節(jié)點(diǎn)就是終點(diǎn)，說明找到一條路徑*/
      {
        showAndSavePath();/*轉(zhuǎn)儲(chǔ)并打印輸出該路徑，返回true*/
        return true;
      }
      Else/*如果不是,繼續(xù)尋路*/
      {
        nNode = cNode.getRelationNodes().get(i);/*從與當(dāng)前起始節(jié)點(diǎn)cNode有連接關(guān)系的節(jié)點(diǎn)集中按順序遍歷得到一個(gè)節(jié)點(diǎn)作為下一次遞歸尋路時(shí)的起始節(jié)點(diǎn)*/
        while(nNode != null)
        {
          if(pNode != null && (nNode == sNode 
              || nNode == pNode 
              || isNodeInStack(nNode)))/*如果nNode是最初的起始節(jié)點(diǎn)或者nNode就是cNode的上一節(jié)點(diǎn)或者nNode已經(jīng)在棧中，說明產(chǎn)生環(huán)路，應(yīng)重新在與當(dāng)前起始節(jié)點(diǎn)有連接關(guān)系的節(jié)點(diǎn)集中尋找nNode*/
          {
            i++;
            if(i>=cNode.getRelationNodes().size())
              nNode = null;
            else
              nNode = cNode.getRelationNodes().get(i);
            continue;
          }
/*以nNode為新的起始節(jié)點(diǎn)，當(dāng)前起始節(jié)點(diǎn)cNode為上一節(jié)點(diǎn)，遞歸調(diào)用尋路方法*/
          if(getPaths(nNode, cNode, sNode, eNode))/*遞歸調(diào)用*/
          {
            stack.pop();/*如果找到一條路徑，則彈出棧頂節(jié)點(diǎn)*/
          }
          i++;/*繼續(xù)在與cNode有連接關(guān)系的節(jié)點(diǎn)集中測試nNode*/
          if(i>=cNode.getRelationNodes().size())
            nNode = null;
          else
            nNode = cNode.getRelationNodes().get(i);
        }
        stack.pop();/*當(dāng)遍歷完所有與cNode有連接關(guān)系的節(jié)點(diǎn)后，說明在以cNode為起始節(jié)點(diǎn)到終點(diǎn)的路徑已經(jīng)全部找到*/
        return false;
      }
    }
    else
      return false;
}