webdriverでスクリーンキャプチャ ref: http://qiita.com/items/34e8d443c543a5ff0591

file0.java

import org.apache.commons.io.FileUtils;
import org.openqa.selenium.OutputType;
import org.openqa.selenium.TakesScreenshot;

File tmpFile = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);
try {
    FileUtils.copyFile(tmpFile, new File("tmp.png"));
} catch (IOException e) {
    e.printStackTrace();
}