String outUrl ="下載後圖片的地址";String destUrl="圖片的網路地址";
saveToFile(src,ourUrl);

public static void saveToFile(String destUrl,String outUrl) {
    FileOutputStream fos = null;
BufferedInputStream bis = null;
HttpURLConnection httpUrl = null;
URL url = null;
    int BUFFER_SIZE = 1024;
    byte[] buf = new byte
 
[BUFFER_SIZE];
    int size = 0;
    try {
        url = new URL(destUrl);
httpUrl = (HttpURLConnection) url.openConnection();
httpUrl.connect();
bis = new BufferedInputStream(httpUrl.getInputStream());
fos = new FileOutputStream(outUrl);
        while ((size = bis.read(buf)) != -1) {
            fos.write(buf, 
 
0, size);
}
        fos.flush();
} catch (IOException e) {
    } catch (ClassCastException e) {
    } finally {
        try {
            fos.close();
bis.close();
httpUrl.disconnect();
} catch (IOException e) {
        } catch (NullPointerException e) {
        }
    }
}