html转为图片(四)：DjNativeSwing网页截图

• 只有这个支持js,css，但是网页超过一定高度，就会截取一半；
• 如果是接口调用的话，因为是线程，所以这个只能运行一次就自动关闭了；使用main方法运行就没有问题
• 引入依赖包：

<dependency>
   <groupId>com.hynnet</groupId>
   <artifactId>DJNativeSwing</artifactId>
   <version>1.0.0</version>
</dependency>
<dependency>
    <groupId>com.hynnet</groupId>
    <artifactId>DJNativeSwing-SWT</artifactId>
    <version>1.0.0</version>
</dependency>
<dependency>
    <groupId>org.eclipse.swt.org.eclipse.swt.win32.win32.x86_64.4.3.swt</groupId>
    <artifactId>org.eclipse.swt.win32.win32.x86_64</artifactId>
    <version>4.3</version>
</dependency>

• 案例：

1.首先在springboot启动页上重写方法：

@SpringBootApplication
public class DjnativeswingApplication {

    public static void main(String[] args) {
        SpringApplicationBuilder builder = new SpringApplicationBuilder(DjnativeswingApplication.class);
        ApplicationContext applicationContext = builder.headless(false).run(args);
        applicationContext.getBean(TestController.class);
//        SpringApplication.run(DjnativeswingApplication.class, args);
    }

}

2.写一个工具类：

public class DjNativeSwingUtil 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", "//");
    // 当网页超出目标大小时 截取
    final static public int maxWidth = 2000;
    final static public int maxHeight = 1600;

//    private static class ExitTrappedException extends SecurityException { }

//    private static void forbidSystemExitCall() {
//        final SecurityManager securityManager = new SecurityManager() {
//            public void checkPermission( Permission permission ) {
//                if( "exitVM".equals( permission.getName() ) ) {
//                    throw new ExitTrappedException() ;
//                }
//            }
//        } ;
//        System.setSecurityManager( securityManager ) ;
//    }

    public  DjNativeSwing(final String file, final String url, final String WithResult) {
        super(new BorderLayout());
        JPanel webBrowserPanel = new JPanel(new BorderLayout());
        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());
        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(WithResult);
                    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, "png", new File(file));
                    } catch (IOException ex) {
                        ex.printStackTrace();
                    }
                    // 退出操作
                    System.exit(0);//关闭jvm同时也关闭了tomcat
                }
            }
        });
        add(panel, BorderLayout.SOUTH);
    }

    // 以javascript脚本获得网页全屏后大小
    public static String getScreenWidthHeight() {

        StringBuffer 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;");

        return jsDimension.toString();
    }
}

3. 截取的代码：

@Configuration
public class TestController {
    public static boolean printUrlScreen2jpg(final String file, final String url, final int width, final int height) {
        NativeInterface.open();
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                String withResult = "var width = " + width + ";var height = " + height + ";return width +':' + height;";
                if (width == 0 || height == 0)
                    withResult = DjNativeSwing.getScreenWidthHeight();

                JFrame frame = new JFrame("网页截图");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                // 加载指定页面，最大保存为640x480的截图
                frame.getContentPane().add(new DjNativeSwing(file, url, withResult), BorderLayout.CENTER);
                frame.setSize(640, 800);
                // 仅初始化，但不显示
                frame.invalidate();

                frame.pack();
                frame.setVisible(false);
            }
        });
        NativeInterface.runEventPump();
        return true;
    }
}

4.接口调用：

  @RequestMapping(value = "/htmltest", produces = "application/json;charset=UTF-8")
    @ResponseBody
    public String htmlGenerator() throws Exception{
        TestController.printUrlScreen2jpg("G:/网页截图.png", "G:/index.html", 1000, 1300);
        return null;
    }