public InputStream getFileStream(String uri){
    BufferedInputStream bin = null;
    ByteArrayOutputStream out = null;
    ByteArrayInputStream inputStream = null;
    try {
        out = new ByteArrayOutputStream();
        URL url = new URL(uri);
        HttpURLConnection c = (HttpURLConnection) url.openConnection();
        c.setRequestMethod("GET"
 
);
        c.setRequestProperty("Charset", "UTF-8");
        bin = new BufferedInputStream(c.getInputStream());

        int size = 0;
        int len = 0;
        byte[] buf = new byte[1024];
        while ((size = bin.read(buf)) != -1) {
            len += size;
            out.write(buf, 0, size);
        }
        inputStream = new 
 
ByteArrayInputStream(out.toByteArray());
    }catch (Exception e){
        logger.error("[Error] get file failed!");
    }finally {
        if( bin!= null){
            try{
                bin.close();
            }catch (IOException e){
                logger.error("close stream error!");
            }
        }
        if
 
( out != null){
            try{
                bin.close();
            }catch (IOException e){
                logger.error("close stream error!");
            }
        }
        if( inputStream != null){
            try{
                bin.close();
            }catch (IOException e){
                logger.error("close stream error!");
            }
        }
    }
    return inputStream;
}

  特別提示，httpURLConnection類引的是sun公司的包，不要錯引為apache的，引了apache的不會報錯，但是拿不到返回流！切記切記！