想抓取某些网站通过servlet生成的图片，简单的就是通过HttpClient来实现：
String url = "http://xxxx/pictureservlet?size=100";
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpResponse response = httpclient.execute(httpGet);
try {
System.out.println(response.getStatusLine());
HttpEntity entity = response.getEntity();
if (entity.isStreaming()) {
String destinationFile = "d://tmp//image.jpg";
OutputStream os = new FileOutputStream(destinationFile);
entity.writeTo(os);
}
} finally {
httpGet.releaseConnection();
}如果使用sbt增加
"org.seleniumhq.selenium" % "selenium-java" % "2.35.0" 就可以使用了。
val webClient = new WebClient
val page: UnexpectedPage = webClient.getPage("http://xxx/pictureservlet?size=100")
val input = page.getWebResponse().getContentAsStream()
val destinationFile = "d://tmp//image.jpg"
val os = new FileOutputStream(destinationFile)
os.write(IOUtils.toByteArray(input))
os.close()
input.close()上面的HttpClient对这种情况也是可行的，直接发送一次首页请求，这个连接是共享的，那么进行下载图片是就认为是有效的请求了。
