Dijkstra算法求最短路径(java) - JAVA

点,放入close
if(nearest==null){
return;
}
close.add(nearest);
open.remove(nearest);
Map childs=nearest.getChild();
for(Node child:childs.keySet()){
if(open.contains(child)){//如果子节点在open中
Integer newCompute=path.get(nearest.getName())+childs.get(child);
if(path.get(child.getName())>newCompute){//之前设置的距离大于新计算出来的距离
path.put(child.getName(), newCompute);
pathInfo.put(child.getName(), pathInfo.get(nearest.getName())+"->"+child.getName());
}
}
}
computePath(start);//重复执行自己,确保所有子节点被遍历
computePath(nearest);//向外一层层递归,直至所有顶点被遍历
}
public void printPathInfo(){
Set> pathInfos=pathInfo.entrySet();
for(Map.Entry pathInfo:pathInfos){
System.out.println(pathInfo.getKey()+":"+pathInfo.getValue());
}
}
/**
* 获取与node最近的子节点
*/
private Node getShortestPath(Node node){
Node res=null;

int minDis=Integer.MAX_VALUE;
Map childs=node.getChild();
for(Node child:childs.keySet()){
if(open.contains(child)){
int distance=childs.get(child);
if(distance minDis=distance;
res=child;
}
}
}
return res;
}
}

Main用于测试Dijkstra对象
[java] www.2cto.com
public class Main {
public static void main(String[] args) {
Dijkstra test=new Dijkstra();
Node start=test.init();
test.computePath(start);
test.printPathInfo();
}
}

打印输出如下：
D:A->D
E:A->F->E
F:A->F
G:A->C->G
B:A->B
C:A->C
H:A->B->H

Dijkstra算法求最短路径(java)(二)