我正在寻找一个开源Java库来为给定的URL生成缩略图.我需要捆绑此功能,而不是呼叫外部服务,例如Amazon或websnapr.
http://www.webrenderer.com/在这篇文章中提到:服务器生成的网页截图,但它是一个商业解决方案.
我希望有一个基于Java的解决方案,但可能需要考虑执行一个外部进程,如khtml2png,或集成html2ps之类的东西.
有什么建议?
首先想到的是使用AWT捕获屏幕抓取(参见下面的代码).您可以查看捕获JEditorPane,JDIC WebBrowser控件或SWT 浏览器(通过AWT嵌入支持).后两者嵌入了原生浏览器(IE,Firefox),因此引入了依赖关系; JEditorPane HTML支持在HTML 3.2处停止.可能这些都不适用于无头系统.
import java.awt.Component; import java.awt.Graphics2D; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import javax.imageio.ImageIO; import javax.swing.JLabel; public class Capture { private static final int WIDTH = 128; private static final int HEIGHT = 128; private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); public void capture(Component component) { component.setSize(image.getWidth(), image.getHeight()); Graphics2D g = image.createGraphics(); try { component.paint(g); } finally { g.dispose(); } } private BufferedImage getScaledImage(int width, int height) { BufferedImage buffer = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D g = buffer.createGraphics(); try { g.drawImage(image, 0, 0, width, height, null); } finally { g.dispose(); } return buffer; } public void save(File png, int width, int height) throws IOException { ImageIO.write(getScaledImage(width, height), "png", png); } public static void main(String[] args) throws IOException { JLabel label = new JLabel(); label.setText("Hello, World!"); label.setOpaque(true); Capture cap = new Capture(); cap.capture(label); cap.save(new File("foo.png"), 64, 64); } }