Cannot transfer a file from one place to another using java codes

I am using somehting like below :

HttpClient httpclient = new DefaultHttpClient();
    HttpGet httpGet = new HttpGet(targerFile);
    HttpResponse response = httpclient.execute(开发者_JS百科httpGet);

    // get the response body as an array of bytes
    HttpEntity entity = response.getEntity();

    // write for the destination file

    InputStream instream = null;
    if (entity != null) {
        instream = entity.getContent();

        ByteArrayOutputStream bytOut = new ByteArrayOutputStream();
        int x;
        do {
            x = instream.read();
            if (x != -1) {

                bytOut.write(x);
                instream.close();
                bytOut.close();
            }
        } while (x != -1);
        FileOutputStream fout = new FileOutputStream(destinationFile);
        fout.write(bytOut.toByteArray());
        fout.close();

but only then i find out the inputstream from httpclient comes closed. so there is no way i can read it more than once. is there any work around for this? or is this not the correct way to do it?

use org.apache.http.util.EntityUtils:

byte[] data = EntityUtils.toByteArray(response.getEntity());
httpClient.getConnectionManager().shutdown();

write that bytearray to a file with FileUtils from commons-io:

FileUtils.writeByteArrayToFile(destinationFile, data);

do not close the streams inside the loop. do that outside the loop after the entire input stream is read.

it looks to me like you're closing your bytOut stream after 1 byte is read. But I would do something like this instead:

String line;
BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent()));
PrintWriter pw = new PrintWriter(new FileOutputStream(destinationFile));
while ((line = reader.readLine()) != null) pw.println(line);
pw.close();
reader.close();

First, your problem is that you're closing the input stream in the loop after the first byte is read. Don't do that.

Second, there is no point in writing to a ByteArrayOutputStream if all you're going to do is to just write it to a FileOutputStream. Write directly to the file instead.

Third, use a byte[] and BufferedInputStream and BufferedOutputStreamso you read more bytes at a time.

Fourth, disregard the above and just use commons-io.