java - 如何使 JUNG 中的节点子集出现在一条直线上？

Question

我正在尝试在 JUNG 中构建一个图表，使图表中的某些节点以不同的方式显示和布局。

这是我目前的代码:

package example.ordering;

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;

import org.apache.commons.collections15.Transformer;
import org.apache.commons.collections15.functors.ChainedTransformer;

import edu.uci.ics.jung.algorithms.layout.FRLayout;
import edu.uci.ics.jung.graph.Graph;
import edu.uci.ics.jung.graph.SparseGraph;
import edu.uci.ics.jung.visualization.VisualizationViewer;
import edu.uci.ics.jung.visualization.renderers.VertexLabelAsShapeRenderer;

public class Main {

    public static void main(String[] args) {

        final JFrame frame = new JFrame();

        frame.add(createGraph());
        frame.setLocationRelativeTo(null);

        frame.pack();

        EventQueue.invokeLater(new Runnable() {

            public void run() {
                frame.setVisible(true);
            }
        });
    }

    private static JPanel createGraph() {

        // TODO fill in the code to create a graph with nodes and order them.
        Graph<GraphNode, String> g1 = new SparseGraph<GraphNode, String>();

        GraphNode A = new GraphNode("A", "u");
        GraphNode B = new GraphNode("B", "u");
        GraphNode a = new GraphNode("a", "l");
        GraphNode b = new GraphNode("b", "l");

        g1.addEdge("AB", A, B);
        // g1.addEdge("CD", "C", "D");

        g1.addEdge("Aa", A, a);
        g1.addEdge("Bb", B, b);

        FRLayout<GraphNode, String> layout = new FRLayout<GraphNode, String>(g1);
        VisualizationViewer<GraphNode, String> vv = new VisualizationViewer<GraphNode, String>(
                layout);

        VertexLabelAsShapeRenderer<GraphNode, String> vlasr = new VertexLabelAsShapeRenderer<GraphNode, String>(
                vv.getRenderContext());

        vv.getRenderContext().setVertexShapeTransformer(vlasr);
        vv.getRenderContext().setVertexLabelTransformer(
                new ChainedTransformer<GraphNode, String>(
                        new Transformer[] { new MyLabeller() }));
        vv.getRenderer().setVertexLabelRenderer(vlasr);

        return vv;
    }

}

class GraphNode {
    public String value;
    public String type;

    public GraphNode(String value, String type) {
        this.value = value;
        this.type = type;
    }

    @Override
    public String toString() {
        return value;
    }

}

class MyLabeller implements Transformer<GraphNode, String> {

    public String transform(GraphNode arg0) {
        if (arg0.type.equals("u")) {
            return arg0.value;
        } else {
            return "";
        }
    }

}

现在 A 和 B 显示为带标签的正确矩形，而小写的 a 和 b 显示为小没有标签的小破折号。

我想要的是小案例节点(类型为“l”)都出现在按字母顺序排序的同一级别。

Answer 1

使用 AggregateLayout，如本示例所示:http://jung.sourceforge.net/site/jung-samples/xref/edu/uci/ics/jung/samples/SubLayoutDemo.html