利用Jung API在eclipse中实现Graph可视化

前言：

    Jung有一套让Graph实现可视化的API，可是在网络上的使用文档少之又少。故在此记下几个使用方法，来源于http://jung.sourceforge.net/doc/index.html及网上部分使用博客。

一、下载jung api

    http://jung.sourceforge.net/download.html 

    至于如何将jar文件导入eclipse，及如何build path请读者自行Google

二、适配API接口

    

    http://jung.sourceforge.net/doc/api/index.html

    在这里有jung的一系列API描述的接口，总体上而言就是使用Graph<L,E>这样一个泛型的接口，其中L是点的泛型，E为边的泛型。

    

假使现在有一个图： Graph<Vertex,Edge> g  其中Vertex是点，Edge是边 ，那么我建立一个无向多重图如下：

    SparseMultigraph<Vertex, Edge> graph = new SparseMultigraph<Vertex, Edge>();

然后，将g中所有的点、边放入新建的graph图中

for(Vertex v: g.vertices()) {
           graph.addVertex(v);
     }

//无向边

for(Edge e: g.edges()) {
         graph.addEdge(e, e.vertices.get(0),e.vertices.get(1));
    }

//有向边

for(Edge e: g.edges()) {
         graph.addEdge(e, e.vertices.get(0), e.vertices.get(1), EdgeType.DIRECTED);
    }

三、具体实现

//设置布局 

Layout<Vertex, Edge> layout = new CircleLayout<Vertex, Edge>(graph);

//设置可视化的的观察器，节点、边的信息如何显示、节点和边的颜色、形态都可以在vv中更改 
   VisualizationViewer<Vertex, Edge> vv = new VisualizationViewer<Vertex, Edge>(layout);

//默认显示节点的label

// vv.getRenderContext().setVertexLabelTransformer(new ToStringLabeller<Vertex>());

//或者利用一个Transformer，将节点的类型也显示出来

vv.getRenderContext().setVertexLabelTransformer(new Transformer<>() {
        public String transform(Vertex v) {
         if(v instanceof Word) return "Word "+v.getLabel();
         else if(v instanceof Person) return "Person "+ v.getLabel();
         else if(v instanceof Computer) return "Computer "+ v.getLabel();
         else if(v instanceof Router) return "Router "+ v.getLabel();
         else if(v instanceof Server) return "Server "+ v.getLabel();
         else if(v instanceof WirelessRouter) return "WirelessRouter "+ v.getLabel();
         else if(v instanceof Movie) return "Movie "+ v.getLabel();
         else if(v instanceof Actor) return "Actor "+ v.getLabel();
         else if(v instanceof Director) return "Director "+ v.getLabel();
         else return null;
        }
   });

//设置节点的颜色，利用一个Vertex - Paint 的Transformer

Transformer<Vertex, Paint> vertexPaint = new Transformer<Vertex, Paint>() { 
             public Paint transform(Vertex v) { 
              if(v instanceof Word || v instanceof Person) return Color.RED;
              
     else if(v instanceof Computer) return Color.BLUE;
     else if(v instanceof Router) return Color.GREEN;
     else if(v instanceof Server) return Color.ORANGE;
     else if(v instanceof WirelessRouter) return Color.RED;
              
     else if(v instanceof Movie) return Color.BLUE;
     else if(v instanceof Actor) return Color.RED;
     else if(v instanceof Director) return Color.GREEN;
     else return null;
    }

// 设置顶点颜色

vv.getRenderContext().setVertexFillPaintTransformer(vertexPaint);

//设置边的文本

//vv.getRenderContext().setEdgeLabelTransformer(new ToStringLabeller<Edge>());    默认显示边的label

//利用Transformer，显示边的label 以及 权值

vv.getRenderContext().setEdgeLabelTransformer(new Transformer<>() {
             public String transform(Edge e) {
                 return (e.toString() + " " + e.getWeight());
             }
         });

//在这里edgeStrokeTransformer显示的是虚线

float dash[] = {10.0f};       
       final Stroke edgeStroke = new BasicStroke(1.0f, BasicStroke.CAP_BUTT,            
         BasicStroke.JOIN_MITER, 10.0f, dash, 0.0f);       

       Transformer<Edge, Stroke> edgeStrokeTransformer = new Transformer<Edge, Stroke>() {           
            public Stroke transform(Edge s) {
             if(s instanceof SameMovieHyperEdge) {
                  return edgeStroke;   
             }
                 return null;
                }      
       };
   // 设置边的线型 
         vv.getRenderContext().setEdgeStrokeTransformer(edgeStrokeTransformer); 

   DefaultModalGraphMouse<Vertex, Edge> gm = new DefaultModalGraphMouse<Vertex, Edge>();
   gm.setMode(Mode.PICKING);  
         vv.setGraphMouse(gm);

    //最后是套话，pack 、 visible  

  
         JFrame myframe = new JFrame();
         myframe.getContentPane().add(vv);
         myframe.setExtendedState(JFrame.MAXIMIZED_BOTH);
         myframe.pack();
         myframe.setVisible(true);