java根据url生成网页截图，缩略图

源地址：http://blog.csdn.net/cping1982/article/details/5353049

public class ShotsPic 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;");
}


public ShotsPic( String url) {
super(new BorderLayout());
JPanel webBrowserPanel = new JPanel(new BorderLayout());
final String fileName = "screenShots.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) {

//动态执行JS 最终返回网页的实际的宽度和高度
String result = (String) webBrowser.executeJavascriptWithResult(jsDimension.toString());

System.out.println(result);

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);
imageSize.height = Math.max(originalSize.height,imageSize.height);

System.out.println(imageSize.width);
System.out.println(imageSize.height);


nativeComponent.setSize(imageSize);
BufferedImage image = new BufferedImage(imageSize.width,imageSize.height, BufferedImage.TYPE_INT_RGB);
nativeComponent.paintComponent(image);

//nativeComponent.setSize(imageSize);
// 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("E:\\"+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() {

JFrame frame = new JFrame("以DJ组件保存指定网页截图");

frame.getContentPane().add(
new ShotsPic("www.qq.com"),
BorderLayout.CENTER);
frame.setSize(1280, 768);
// 仅初始化，但不显示
frame.invalidate();
frame.pack();
frame.setVisible(false);
}
});
NativeInterface.runEventPump();
}

}

程序需要三个包:,下载地址请参考原文地址!

注：如果网速不是很好，会对截图有一定的影响！