使用DJNativeSwing实现网页截图System.exit(0);把tomcat也退出了

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import chrriis.dj.nativeswing.swtimpl.NativeComponent;
import chrriis.dj.nativeswing.swtimpl.NativeInterface;
import chrriis.dj.nativeswing.swtimpl.components.JWebBrowser;
import chrriis.dj.nativeswing.swtimpl.components.WebBrowserAdapter;
import chrriis.dj.nativeswing.swtimpl.components.WebBrowserEvent;
public class Main extends JPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
// 行分隔符
final static public String LS = System.getProperty("line.separator", "/n");
// 文件分割符
final static public String FS = System.getProperty("file.separator", "//");
//以javascript脚本获得网页全屏后大小
final static StringBuffer jsDimension;

static {
jsDimension = new StringBuffer();
jsDimension.append("var width = 0;").append(LS);
jsDimension.append("var height = 0;").append(LS);
jsDimension.append("if(document.documentElement) {").append(LS);
jsDimension.append(
" width = Math.max(width, document.documentElement.scrollWidth);")
.append(LS);
jsDimension.append(
" height = Math.max(height, document.documentElement.scrollHeight);")
.append(LS);
jsDimension.append("}").append(LS);
jsDimension.append("if(self.innerWidth) {").append(LS);
jsDimension.append(" width = Math.max(width, self.innerWidth);")
.append(LS);
jsDimension.append(" height = Math.max(height, self.innerHeight);")
.append(LS);
jsDimension.append("}").append(LS);
jsDimension.append("if(document.body.scrollWidth) {").append(LS);
jsDimension.append(
" width = Math.max(width, document.body.scrollWidth);")
.append(LS);
jsDimension.append(
" height = Math.max(height, document.body.scrollHeight);")
.append(LS);
jsDimension.append("}").append(LS);
jsDimension.append("return width + ':' + height;");
}
//DJNativeSwing组件请于http://djproject.sourceforge.net/main/index.html下载
public Main(final String url, final int maxWidth, final int maxHeight) {
super(new BorderLayout());
JPanel webBrowserPanel = new JPanel(new BorderLayout());
final String fileName = System.currentTimeMillis() + ".jpg";
final JWebBrowser webBrowser = new JWebBrowser(null);
webBrowser.setBarsVisible(false);
webBrowser.navigate(url);
webBrowserPanel.add(webBrowser, BorderLayout.CENTER);
add(webBrowserPanel, BorderLayout.CENTER);
JPanel panel = new JPanel(new FlowLayout(FlowLayout.CENTER, 4, 4));
webBrowser.addWebBrowserListener(new WebBrowserAdapter() {
// 监听加载进度
public void loadingProgressChanged(WebBrowserEvent e) {
// 当加载完毕时
if (e.getWebBrowser().getLoadingProgress() == 100) {
String result = (String) webBrowser
.executeJavascriptWithResult(jsDimension.toString());
int index = result == null ? -1 : result.indexOf(":");
NativeComponent nativeComponent = webBrowser
.getNativeComponent();
Dimension originalSize = nativeComponent.getSize();
Dimension imageSize = new Dimension(Integer.parseInt(result
.substring(0, index)), Integer.parseInt(result
.substring(index + 1)));
imageSize.width = Math.max(originalSize.width,
imageSize.width + 50);
imageSize.height = Math.max(originalSize.height,
imageSize.height + 50);
nativeComponent.setSize(imageSize);
BufferedImage image = new BufferedImage(imageSize.width,
imageSize.height, BufferedImage.TYPE_INT_RGB);
nativeComponent.paintComponent(image);
nativeComponent.setSize(originalSize);
// 当网页超出目标大小时
if (imageSize.width > maxWidth
|| imageSize.height > maxHeight) {
//截图部分图形
image = image.getSubimage(0, 0, maxWidth, maxHeight);
/*此部分为使用缩略图
int width = image.getWidth(), height = image
.getHeight();
AffineTransform tx = new AffineTransform();
tx.scale((double) maxWidth / width, (double) maxHeight
/ height);
AffineTransformOp op = new AffineTransformOp(tx,
AffineTransformOp.TYPE_NEAREST_NEIGHBOR);
//缩小
image = op.filter(image, null);*/
}
try {
// 输出图像
ImageIO.write(image, "jpg", new File(fileName));
} catch (IOException ex) {
ex.printStackTrace();
}
// 退出操作
System.exit(0);
}
}
}
);
add(panel, BorderLayout.SOUTH);
}
public static void main(String[] args) {
NativeInterface.open();
SwingUtilities.invokeLater(new Runnable() {
public void run() {
// SWT组件转Swing组件，不初始化父窗体将无法启动webBrowser
JFrame frame = new JFrame("以DJ组件保存指定网页截图");
// 加载指定页面，最大保存为640x480的截图
frame.getContentPane().add(
new Main("http://blog.csdn.net/cping1982", 640, 480),
BorderLayout.CENTER);
frame.setSize(800, 600);
// 仅初始化，但不显示
frame.invalidate();
frame.pack();
frame.setVisible(false);
}
});
NativeInterface.runEventPump();
}
}

System.exit(0);把tomcat也退出了,怎么解决。