狄克斯特拉算法

package cn.zhaoyuening.algorithms.dijkstra;import java.util.HashMap;import java.util.HashSet;import java.util.Map;import java.util.Set;class Vertex{    private String name;    private Map<Vertex, Integer> adjMap = new HashMap<>();    public Vertex(String name){        this.name = name;    }    public String getName() {        return name;    }    public Vertex setName(String name) {        this.name = name;        return this;    }    public Integer getValByVertex(Vertex vertex) {        return adjMap.get(vertex);    }    public Vertex addAdj(Vertex v, Integer val) {        adjMap.put(v, val);        return this;    }    public Set<Vertex> getAdjSet() {        return adjMap.keySet();    }    @Override    public String toString() {        return this.name;    }}public class Dijkstra {    private Map<Vertex, Integer> valMap;    private Set<Vertex> handledVertex;    public Integer miniVal(Vertex startVertex, Vertex endVertex) {        valMap = new HashMap<Vertex, Integer>();        valMap.put(startVertex, 0);        handledVertex = new HashSet<>();        Vertex tmpVertex = startVertex;        Set<Vertex> adjSet = null;        while (tmpVertex != null) {            handledVertex.add(tmpVertex);            adjSet = tmpVertex.getAdjSet();            for (Vertex v :                    adjSet) {                updateValMap(v, valMap.get(tmpVertex)+tmpVertex.getValByVertex(v));//                找下个最小距离点            }            tmpVertex = findMiniValVertex();        }        return valMap.get(endVertex);    }    public Vertex findMiniValVertex() {        Vertex miniVertex = null;        Integer miniVal = Integer.MAX_VALUE;        int tmpVal = 0;        for (Vertex v :                valMap.keySet()) {            if (handledVertex.contains(v)) {                continue;            }            tmpVal = valMap.get(v);            if (miniVal > tmpVal) {                miniVal = tmpVal;                miniVertex = v;            }        }        return miniVertex;    }    public boolean updateValMap(Vertex vertex,Integer val) {        if (!valMap.containsKey(vertex)||val < valMap.get(vertex)) {            valMap.put(vertex, val);            return true;        }        return false;    }    public static void main(String[] args) {        Vertex s = new Vertex("S");        Vertex a = new Vertex("A");        Vertex b = new Vertex("B");        Vertex e = new Vertex("E");        s.addAdj(a, 6);        s.addAdj(b, 2);        b.addAdj(a, 3);        a.addAdj(e, 1);        Dijkstra dijkstra = new Dijkstra();        Integer val = dijkstra.miniVal(s, e);        System.out.println(val);    }}