java图的邻接矩阵的表示和实现

邻接矩阵表示的带权图。。。
首先创建了一个带权值的边类，在图中插入图的权值，所谓权值就是边上的数字，可以表示两个顶点之间的边的含义（可以是距离，路费。。。）

public class Edge implements Comparable<Edge> {

	public int start,dest,weight;
	
	public Edge(int start,int dest,int weight){
		this.start = start;
		this.dest = dest;
		this.weight = weight;
	}
	
	public String toString(){
		return "("+start+","+dest+","+weight+")";
	}
	public int compareTo(Edge e) {
		// TODO Auto-generated method stub
		if(this.start!=e.start)
			return this.start - e.start;
		return this.dest - e.dest;
	}

}

其次创建邻接矩阵带权图类，在此类中用到的SeqList<T>是我前几天所写的一个顺序表类，主要是用来存放顶点集合的，可以自己定义也可以用jdk中给的顺序表

public class AdjMatrixGraph<T> {
	protected SeqList<T> vertexlist;			//顺序表存储的顶底集合
	protected int[][] adjmatrix;				//图的邻接矩阵，用二维数组表示
	private final int MAX_WEIGHT = 99999;		//设置最大权值，设置成常量
	public AdjMatrixGraph(int size){
		size = size<10?10:size;
		this.vertexlist = new SeqList<T>(size); //构造容量为size的空顺序表
		this.adjmatrix = new int[size][size];   
		
		for(int i=0;i<size;i++){				//初始化邻接矩阵
			for(int j=0;j<size;j++){
				this.adjmatrix[i][j] = (i==j)?0:MAX_WEIGHT;
			}
		}
	}
		
		public AdjMatrixGraph(T[] vertices,Edge[] edges){
			this(vertices.length);
			if(vertices == null)
				return;
			for(int i=0;i<vertices.length;i++)
				insertVertex(vertices[i]);
			if(edges!=null)
					for(int j=0;j<edges.length;j++)
						insertEdge(edges[j]);
		}
	
		public int vertexCount(){return this.vertexlist.length();}		//返回定点顺序表的元素个数
		
		public T get(int i){return this.vertexlist.get(i);}			 	//返回第i个定点的元素
		
		public int getWeight(int i,int j){return this.adjmatrix[i][j];}	//返<vi,vj>边的权值
		
		public String toString(){
			String str = "顶点集合:"+this.vertexlist.toString()+"\n邻接矩阵：\n";
			int n = this.vertexCount();
			for(int i=0;i<n;i++){
				for(int j=0;j<n;j++)
					str += this.adjmatrix[i][j] == MAX_WEIGHT?" $":" "+this.adjmatrix[i][j];
				str +="\n";
			}
			return str;
		}
		
		public int insertVertex(T x){
			this.vertexlist.append(x);				//顺序表追加元素，自动扩充
			if(this.vertexCount()>this.adjmatrix.length){		//若二维数组不足,则扩充
				int temp[][] = adjmatrix,i,j;					//定义了局部变量i,j;
				this.adjmatrix = new int[temp.length*2][temp.length*2];		//二维数组扩充2倍
				for(i=0;i<temp.length;i++){
					for(j=0;j<temp.length;j++)
						this.adjmatrix[i][j] = temp[i][j];
					for(j=temp.length;j<temp.length*2;j++)
						this.adjmatrix[i][j] = MAX_WEIGHT;
				}
				for(i=temp.length;i<temp.length*2;i++)
					for(j=0;j<temp.length*2;j++)
						this.adjmatrix[i][j] = (i == j)?0:MAX_WEIGHT;
			}
			return this.vertexlist.length()-1;					//返回插入顶点的序号			
		}
		
		public void  insertEdge(int i,int j,int weight){       //插入一条边
			int n = this.vertexCount();
			if(i>=0&&i<n&&j>=0&&j<n&&this.adjmatrix[i][j]==MAX_WEIGHT&&i!=j)
				this.adjmatrix[i][j] = weight;
		}
		
		public void insertEdge(Edge edge){
			this.insertEdge(edge.start, edge.dest, edge.weight);
		}
			
		public void removeEdge(int i,int j){					//删除一条边
			if(i>=0&&i<vertexCount()&&j>=0&&j<vertexCount()&&i!=j)
				this.adjmatrix[i][j] = MAX_WEIGHT;
		}
		
		public void removeVertex(int i){						//删除顶点以及和顶点有关系的边
			int n = this.vertexCount();
			if(i<0||i>n)
				return;
			this.vertexlist.remove(i);
			for(int j=0;j<i;j++)
				for(int k=i+1;k<n;k++)
					this.adjmatrix[j][k-1] = this.adjmatrix[j][k];		//元素向左移一行
			for(int j=i+1;j<n;j++)
				for(int k=0;k<i;k++)
					this.adjmatrix[j-1][k] = this.adjmatrix[j][k];		//元素向上移一行
			
			for(int j=i+1;j<n;j++)
				for(int k=i+1;k<n;k++)
					this.adjmatrix[j-1][k-1] = this.adjmatrix[j][k];
		}
		
		public static void main(String[] args){
			String[] verices = {"A","B","C","D","E"};
			Edge edges[] = {new Edge(0,1,5),new Edge(0,3,2),new Edge(1,0,5),
							new Edge(1,2,7),new Edge(1,3,6),new Edge(2,1,7),
							new Edge(2,3,8),new Edge(2,4,3),new Edge(3,0,2),
							new Edge(3,1,6),new Edge(3,2,8),new Edge(3,4,9),
							new Edge(4,2,3),new Edge(4,3,9)};
			AdjMatrixGraph<String> graph = new AdjMatrixGraph<String>(verices,edges);
			System.out.println("带权无向图"+graph.toString());
			System.out.println("插入顶点F,插入边(A,F,9),删除顶点C,删除边(D,E)");
			int i = graph.insertVertex("F");
			graph.insertEdge(0,i,9);
			graph.insertEdge(i,0,9);
			graph.removeVertex(2);
			graph.removeEdge(2, 3);
			graph.removeEdge(3, 2);
			System.out.println(graph.toString());
		}
}

输出结果如下（其中"$"表示最大权值）

带权无向图顶点集合:A B C D E 
邻接矩阵：
 0 5 $ 2 $
 5 0 7 6 $
 $ 7 0 8 3
 2 6 8 0 9
 $ $ 3 9 0

插入顶点F,插入边(A,F,9),删除顶点C,删除边(D,E)
顶点集合:A B D E F 
邻接矩阵：
 0 5 2 $ 9
 5 0 6 $ $
 2 6 0 $ $
 $ $ $ 0 $
 9 $ $ $ 0