File download from url

public static Logger APP_LOGS = Logger.getLogger(HttpDownloadUtility.class.getName());

private static final int BUFFER_SIZE = 4096;

/**

* Downloads a file from a URL

*

* @param fileURL

* HTTP URL of the file to be downloaded

* @param saveDir

* path of the directory to save the file

* @throws IOException

*/

public static void downloadFile(String fileURL, String saveDir) {

try {

URL url = new URL(fileURL);

HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();

int responseCode = httpConn.getResponseCode();

// always check HTTP response code first

if (responseCode == HttpURLConnection.HTTP_OK) {

String fileName = "";

String disposition = httpConn.getHeaderField("Content-Disposition");

String contentType = httpConn.getContentType();

int contentLength = httpConn.getContentLength();

if (disposition != null) {

// extracts file name from header field

int index = disposition.indexOf("filename=");

if (index > 0) {

fileName = disposition.substring(index + 10, disposition.length() - 1);

}

} else {

// extracts file name from URL

fileName = fileURL.substring(fileURL.lastIndexOf("/") + 1, fileURL.length());

}

System.out.println("Content-Type = " + contentType);

System.out.println("Content-Disposition = " + disposition);

System.out.println("Content-Length = " + contentLength);

System.out.println("fileName = " + fileName);

// opens input stream from the HTTP connection

InputStream inputStream = httpConn.getInputStream();

String saveFilePath = saveDir + File.separator + fileName;

// opens an output stream to save into file

FileOutputStream outputStream = new FileOutputStream(saveFilePath);

int bytesRead = -1;

byte[] buffer = new byte[BUFFER_SIZE];

while ((bytesRead = inputStream.read(buffer)) != -1) {

outputStream.write(buffer, 0, bytesRead);

}

outputStream.close();

inputStream.close();

System.out.println(fileName + " File downloaded successfully");

APP_LOGS.info(fileName + " File downloaded successfully");

} else {

APP_LOGS.error("No file to download. Server replied HTTP code: " + responseCode);

System.out.println("No file to download. Server replied HTTP code: " + responseCode);

}

httpConn.disconnect();

} catch (Exception e) {

APP_LOGS.error("Could not able to download file : " + e.getMessage());

}

}