public class GraphView extends javax.swing.JPanel {
  private Graph<? extends Displayable> graph;
  
  public GraphView(Graph<? extends Displayable> graph) {
    this.graph = graph;
  }
  
  protected void paintComponent(java.awt.Graphics g) {
    super.paintComponent(g);
    
    // Draw vertices
    java.util.List<? extends Displayable> vertices 
      = graph.getVertices();    
    for (int i = 0; i < graph.getSize(); i++) {
      int x = vertices.get(i).getX();
      int y = vertices.get(i).getY();
      String name = vertices.get(i).getName();
      
      g.fillOval(x - 8, y - 8, 16, 16); // Display a vertex
      g.drawString(name, x - 12, y - 12); // Display the name
    }
    
    // Draw edges for pair of vertices
    for (int i = 0; i < graph.getSize(); i++) {
      java.util.List<Integer> neighbors = graph.getNeighbors(i);
      for (int j = 0; j < neighbors.size(); j++) {
        int v = neighbors.get(j);
        int x1 = graph.getVertex(i).getX();
        int y1 = graph.getVertex(i).getY();
        int x2 = graph.getVertex(v).getX();
        int y2 = graph.getVertex(v).getY();
        
        g.drawLine(x1, y1, x2, y2); // Draw an edge for (i, v)
      }
    }
  }
}