是否可以通过使用循环向图形添加边？我正在解析一个字符串以确定适当的边缘和标签。出于某种原因，它只会为用于迭代字符串的 while 循环的第一轮添加边。对于所有其他人，将出现以下消息...
警告：一条边被删除，因为底层的 JGraphT 图拒绝创建它。当底层图的约束被违反时，这种情况可能会发生，例如，尝试向禁止它们的图添加平行边或自环。为避免此消息，请确保使用合适的底层 JGraphT 图。
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import org.jgraph.*;
import org.jgraph.graph.*;
import org.jgrapht.*;
import org.jgrapht.ext.*;
import org.jgrapht.graph.*;
// resolve ambiguity
import org.jgrapht.graph.DefaultEdge;
public class JGraphAdapterDemo
extends JApplet
{
private static final long serialVersionUID = 3256444702936019250L;
private static final Color DEFAULT_BG_COLOR = Color.decode("#FAFBFF");
private static final Dimension DEFAULT_SIZE = new Dimension(530, 320);
static ListenableGraph<String, String> g =
new ListenableDirectedMultigraph<String, String>(String.class);
static int [] finalStates = new int[10];
static int startState = 0;
static char tran = ' ';
static int endState = 0;
private JGraphModelAdapter<String,String> jgAdapter;
public static void main(String [] args)
{
JGraphAdapterDemo applet = new JGraphAdapterDemo();
applet.init();
JFrame frame = new JFrame();
frame.getContentPane().add(applet);
frame.setTitle("JGraphT Adapter to JGraph Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
public void init()
{
// create a JGraphT graph
ListenableGraph<String, String> g =
new ListenableDirectedMultigraph<String, String>(String.class);
// create a visualization using JGraph, via an adapter
jgAdapter = new JGraphModelAdapter<String, String>(g);
JGraph jgraph = new JGraph(jgAdapter);
adjustDisplaySettings(jgraph);
getContentPane().add(jgraph);
resize(DEFAULT_SIZE);
int numStates = 4;
int numSymbols;
int currentState;
int i = 0;
String input = "4 2 0 2 -1 0 a 1 1 b 3 2 c 2 3 c 3 -1"; //place input String here
int readInt = 0;
int j = 0;
String str = "";
int place = 0;
String fState;
//read in numStates, numSymbols, initialState
i=0;
//parse string
i = input.indexOf(" ",0);
str = input.substring(0,i); //number of states
numStates = Integer.parseInt(str); //convert to int
for(int k = 0; k< numStates; k++){
g.addVertex("q"+k);
}
i++;
j = i;
i=input.indexOf(" ",j);
str = input.substring(j,i); //number of symbols
numSymbols = Integer.parseInt(str);
i++;
j = i;
i=input.indexOf(" ",j);
str = input.substring(j,i); //initial state
currentState = Integer.parseInt(str);
i++;
j = i;
//read in finalStates
while(readInt!=-1){
i=input.indexOf(" ",j);
fState = input.substring(j,i); //a final state
readInt = Integer.parseInt(fState);
if(readInt!=-1){
finalStates[place] = readInt;
i++;
j = i;
place++;
}//end if
}//end while
i++;
j = i;
String sState;
String eState;
while(startState!=-1&& j<(input.length()-2)){ //until end of file
i=input.indexOf(" ",j);
sState = input.substring(j,i); //start state
startState = Integer.parseInt(sState); //convert to int
if(startState!=-1){
i++;
j = i;
String cStr = "";
tran = input.charAt(i); //transition
cStr = cStr + tran;
i = i+2;
j=i;
i=input.indexOf(" ",j);
eState = input.substring(j,i); //end state
endState = Integer.parseInt(eState);
i++;
j=i;
String one = "q"+startState;
String two = "q"+endState;
System.out.println(one+ two +" "+cStr);
g.addEdge(one, two, cStr);
//drawEdge(one, two, cStr);
}//end if
}//end while
}
public static void drawEdge(String v, String v1, String label){
System.out.println(v +" "+v1+ " "+label);
g.addEdge(v,v1,label);
}
private void adjustDisplaySettings(JGraph jg)
{
jg.setPreferredSize(DEFAULT_SIZE);
Color c = DEFAULT_BG_COLOR;
String colorStr = null;
try {
colorStr = getParameter("bgcolor");
} catch (Exception e) {
}
if (colorStr != null) {
c = Color.decode(colorStr);
}
jg.setBackground(c);
}
@SuppressWarnings("unchecked") // FIXME hb 28-nov-05: See FIXME below
private void positionVertexAt(Object vertex, int x, int y)
{
DefaultGraphCell cell = jgAdapter.getVertexCell(vertex);
AttributeMap attr = cell.getAttributes();
Rectangle2D bounds = GraphConstants.getBounds(attr);
Rectangle2D newBounds =
new Rectangle2D.Double(
x,
y,
bounds.getWidth(),
bounds.getHeight());
GraphConstants.setBounds(attr, newBounds);
// TODO: Clean up generics once JGraph goes generic
AttributeMap cellAttr = new AttributeMap();
cellAttr.put(cell, attr);
jgAdapter.edit(cellAttr, null, null, null);
}
//~ Inner Classes ----------------------------------------------------------
/**
* a listenable directed multigraph that allows loops and parallel edges.
// */
private static class ListenableDirectedMultigraph<V, E>
extends DefaultListenableGraph<V, E>
implements DirectedGraph<V, E>
{
private static final long serialVersionUID = 1L;
ListenableDirectedMultigraph(Class<E> edgeClass)
{
super(new DirectedMultigraph<V, E>(edgeClass));
}
}
}