是否有可能确定从URL读取的BufferedImage
是一个GIF
图片?我想检查MIME类型,而不是文件扩展名.gif。
谢谢
是否有可能确定从URL读取的BufferedImage
是一个GIF
图片?我想检查MIME类型,而不是文件扩展名.gif。
谢谢
从URL读取前几个字节,如果是GIF图像,它应该以“魔术词”GIF89a
开头。
public static String read(InputStream input) throws IOException {
ImageInputStream stream = ImageIO.createImageInputStream(input);
Iterator iter = ImageIO.getImageReaders(stream);
if (!iter.hasNext()) {
return null;
}
ImageReader reader = (ImageReader) iter.next();
ImageReadParam param = reader.getDefaultReadParam();
reader.setInput(stream, true, true);
BufferedImage bi;
try {
bi = reader.read(0, param);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
reader.dispose();
try {
stream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return reader.getFormatName();
}
public static void main(String[] args) throws MalformedURLException, IOException {
URL url = new URL("http://p1.pstatp.com/large/efa0004d2238045fb9f");
URLConnection connection = url.openConnection();
connection.setConnectTimeout(3000);
connection.setReadTimeout(3000);
InputStream in = null;
try {
in = connection.getInputStream();
String format = read(in);
System.out.print(format);
} catch (Exception e) {
}
}