@Override
protected void doDownload(Resource rsrc) throws IOException {
// download the resource from the specified URL
URLConnection conn = ConnectionUtil.open(rsrc.getRemote());
conn.connect();
// make sure we got a satisfactory response code
if (conn instanceof HttpURLConnection) {
HttpURLConnection hcon = (HttpURLConnection) conn;
if (hcon.getResponseCode() != HttpURLConnection.HTTP_OK) {
throw new IOException(
"Unable to download resource " + rsrc.getRemote() + ": " + hcon.getResponseCode());
}
}
long actualSize = conn.getContentLength();
log.info("Downloading resource", "url", rsrc.getRemote(), "size", actualSize);
InputStream in = null;
FileOutputStream out = null;
long currentSize = 0L;
try {
in = conn.getInputStream();
out = new FileOutputStream(rsrc.getLocal());
int read;
// TODO: look to see if we have a download info file
// containing info on potentially partially downloaded data;
// if so, use a "Range: bytes=HAVE-" header.
// read in the file data
while ((read = in.read(_buffer)) != -1) {
// write it out to our local copy
out.write(_buffer, 0, read);
// if we have no observer, then don't bother computing download statistics
if (_obs == null) {
continue;
}
// note that we've downloaded some data
currentSize += read;
updateObserver(rsrc, currentSize, actualSize);
}
} finally {
StreamUtil.close(in);
StreamUtil.close(out);
}
}
@Override
protected long checkSize(Resource rsrc) throws IOException {
URLConnection conn = ConnectionUtil.open(rsrc.getRemote());
try {
// if we're accessing our data via HTTP, we only need a HEAD request
if (conn instanceof HttpURLConnection) {
HttpURLConnection hcon = (HttpURLConnection) conn;
hcon.setRequestMethod("HEAD");
hcon.connect();
// make sure we got a satisfactory response code
if (hcon.getResponseCode() != HttpURLConnection.HTTP_OK) {
throw new IOException(
"Unable to check up-to-date for " + rsrc.getRemote() + ": " + hcon.getResponseCode());
}
}
return conn.getContentLength();
} finally {
// let it be known that we're done with this connection
conn.getInputStream().close();
}
}