java graph width_java jgrapht 显示Graph 模型（转）

A couple of years ago I came across a Java-based library for graph visualization – JGraph/JGraphT. Recently, I had the chance to play with it in a real context.

Here is a short step-by-step guide to create a simple applet:

Create a Java-project in eclipse

Download the library from http://jgrapht.org/ and extract it

Add ‘jgrapht-jdk1.6.jar’ to the project’s build path

Add a new class ‘GraphTest.java’ to the project.

Copy the code below into ‘GraphTest.java’ (...or download the attached file)

Run as applet

package com;

import java.awt.Color;

import java.awt.Dimension;

import java.awt.Point;

import java.awt.geom.Rectangle2D;

import java.util.HashMap;

import java.util.Map;

import javax.swing.JApplet;

import javax.swing.undo.UndoableEdit;

import org.jgraph.JGraph;

import org.jgraph.graph.AttributeMap;

import org.jgraph.graph.ConnectionSet;

import org.jgraph.graph.DefaultGraphCell;

import org.jgraph.graph.GraphConstants;

import org.jgraph.graph.ParentMap;

import org.jgrapht.ListenableGraph;

import org.jgrapht.ext.JGraphModelAdapter;

import org.jgrapht.graph.ListenableDirectedGraph;

import org.jgrapht.graph.DefaultEdge;

@SuppressWarnings("serial")

/**

* A demo applet that shows how to use JGraph to visualize JGraphT graphs.

*

* @author Barak Naveh, edited by Martin Bäumer in Feb 2011

*

* @since Aug 3, 2003

*/

public class GraphTest extends JApplet {

private static final Color DEFAULT_BG_COLOR = Color.decode( "#FAFBFF" );

private static final Dimension DEFAULT_SIZE = new Dimension( 530, 320 );

@SuppressWarnings("rawtypes")

private JGraphModelAdapter jgAdapter;

@SuppressWarnings({ "unchecked", "rawtypes" })

/**

* Initialize the applet @see java.applet.Applet#init().

*/

public void init( ) {

// create a JGraphT graph

ListenableGraph g = new ListenableDirectedGraph( DefaultEdge.class );

// create a visualization using JGraph, via an adapter

jgAdapter = new JGraphModelAdapter( g );

JGraph jgraph = new JGraph( jgAdapter );

// add some hard-coded sample data (graph manipulated via JGraphT)

//First the vertices

g.addVertex( "v1" );

g.addVertex( "v2" );

g.addVertex( "v3" );

g.addVertex( "v4" );

//...then the edges

g.addEdge( "v1", "v2" );

g.addEdge( "v2", "v3" );

g.addEdge( "v3", "v1" );

g.addEdge( "v4", "v3" );

// a ConnectionSet is another way of storing edges. Each connection stores information about the edge's nodes and its origin/source

// This ConnectionSet is necessary for the visualization

ConnectionSet cs=new ConnectionSet();

cs.connect("v1", "v2", true);

cs.connect("v2", "v3", true);

cs.connect("v3", "v1", true);

cs.connect("v4", "v3", true);

adjustDisplaySettings( jgraph );

getContentPane( ).add( jgraph );

resize( DEFAULT_SIZE );

// position vertices nicely within JGraph component

positionVertexAt( "v1", 130, 40, cs );

positionVertexAt( "v2", 60, 200, cs );

positionVertexAt( "v3", 310, 230, cs );

positionVertexAt( "v4", 380, 70, cs );

}

/**

* a method for general settings of the applet

* @param jg

*/

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({ "rawtypes", "unchecked" })

/**

* Set a position for the vertices

*/

private void positionVertexAt( Object vertex, int x, int y , ConnectionSet cs) {

DefaultGraphCell cell = jgAdapter.getVertexCell( vertex );

AttributeMap vertexAttributes=cell.getAttributes();

Rectangle2D rect=vertexAttributes.createRect(new Point(x,y),50);

Map attr = cell.getAttributes();

GraphConstants.setBounds( attr,rect);

Map cellAttr = new HashMap( );

cellAttr.put( cell, attr );

UndoableEdit[] e=null;

ParentMap m=new ParentMap();

jgAdapter.edit(cellAttr, cs, m, e);

}

}