Java tutorial
import java.io.File; import java.util.Iterator; import javax.imageio.ImageIO; public class Main { public static void main(String[] argv) throws Exception { boolean b; b = canWriteMimeType("image/jpg"); // false b = canWriteMimeType("image/jpeg"); // true } // Returns true if the specified mime type can be written public static boolean canWriteMimeType(String mimeType) { Iterator iter = ImageIO.getImageWritersByMIMEType(mimeType); return iter.hasNext(); } }