JGraphT镜像创建

Question

我需要创建一个有向图和一个显示此图的图像。

我尝试使用DirectedGraph创建图形，它在内部存储正确，我测试了它，但我无法从它创建一个图像来显示在E4 RCP应用程序中。

这是我的代码：

import org.jgraph.JGraph;
import org.jgrapht.DirectedGraph;
import org.jgrapht.ext.JGraphModelAdapter;
import org.jgrapht.graph.DefaultDirectedGraph;
import org.jgrapht.graph.DefaultEdge;

DirectedGraph <String, DefaultEdge> graph = new DefaultDirectedGraph<String, DefaultEdge>(DefaultEdge.class);
addVertexes();
addEdges();

//Create image from graph 
JGraphModelAdapter<String, DefaultEdge> graphModel = new JGraphModelAdapter<String, DefaultEdge>(graph);
JGraph jgraph = new JGraph (graphModel);
BufferedImage img = jgraph.getImage(Color.WHITE, 5);

但是显然img总是空的。为什么会这样?我如何才能将其更改为正常工作？

Answer 1

只需阅读JGraphX并尝试使用它，所以对我来说它工作得很好！这是我现在代码的一个例子(减少了顶点和边的例子)。

mxGraph graphMx = new mxGraph();

graphMx.insertVertex(graphMx.getDefaultParent(), "Start", "Start", 0.0, 0.0, 50.0, 30.0, "rounded");
graphMx.insertVertex(graphMx.getDefaultParent(), "Ende", "Ende", 0.0, 0.0, 50.0, 30.0, "rounded");

graphMx.insertEdge(graphMx.getDefaultParent(), null, "", ((mxGraphModel)graphMx.getModel()).getCell("Start"), ((mxGraphModel)graphMx.getModel()).getCell("Ende"));

mxIGraphLayout layout = new mxHierarchicalLayout(graphMx);
layout.execute(graphMx.getDefaultParent());

BufferedImage image = mxCellRenderer.createBufferedImage(graphMx, null, 1, Color.WHITE, true, null);
return image;

Answer 2

您还可以将其放在JFRAME上，并从该帧生成图像。-Jan

Answer 3

我的答案类似于@HexFlex，但我让它以同样的方式工作，尽管我不确定如何自定义绘图：

String GRAPH_FILE_PATH = "somwhere/u/want.png";

public static <V, E> File drawGraph(Graph<V, E> graph) throws IOException {
    JGraphXAdapter<V, E> graphAdapter = new JGraphXAdapter<V, E>(graph);
    mxIGraphLayout layout = new mxCircleLayout(graphAdapter);
    layout.execute(graphAdapter.getDefaultParent());
    BufferedImage image = mxCellRenderer.createBufferedImage(graphAdapter, null, 2, new Color(0f,0f,0f,.5f), true, null);
    File imgFile = new File(GRAPH_FILE_PATH);
    ImageIO.write(image, "PNG", imgFile);
    return imgFile;
}

编辑:顺便说一句，代码来自https://www.baeldung.com/jgrapht，我只是把它重构成一个函数