First, everyone needs to know i'm relatively new to Java coding. To be more precise i'm completely new to Object Oriented Programming.
To the question.
I am trying to create a download class that updates a progress bar it was given to show its progress. And possibly anything else I decide to give it in the future to update.
The issue currently is that, in my head, this shouldn't work. I can do anything i want on the "main" method and the GUI is still responsive and quick. In my experience in past programming, this is not possible unless i thread the GUI. Why is this?
Since it works, is this ok to do it this way?
Class Main
package atomicElectronics;
import java.io.IOException;
import atomicElectronics.physical.AtomFrame;
import atomicElectronics.utility.Download;
public class Initial {
static AtomFrame atomLauncher;
public static void main(String[] args) {
atomLauncher = new AtomFrame();
atomLauncher.start();
System.out.println(Integer.MAX_VALUE);
Download theDownload = new Download();
theDownload.fileProgressBar(atomLauncher.progressBar);
try {
theDownload.exicute("http://download.videolan.org/pub/videolan/vlc/last/win64/vlc-2.1.3-win64.exe", "C:\\Users\\TrinaryAtom\\AppData\\Roaming");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// TODO Add Download Methods
// theDownload.updateBarTotal(JProgressBar);
// theDownload.updateLabelSpeed(String);
// theDownload.updateLabelTotal(String);
// theDownload.addFile(File);
// theDownload.addFiles(Files);
}
}
Class AtomFrame
package atomicElectronics.physical;
import javax.swing.JFrame;
import java.awt.FlowLayout;
import javax.swing.JProgressBar;
public class AtomFrame extends JFrame{
public JProgressBar progressBar;
private static final long serialVersionUID = 4010489530693307355L;
public static void main(String[] args){
AtomFrame testFrame = new AtomFrame();
testFrame.start();
}
public AtomFrame(){
initializeComponents();
}
public void initializeComponents(){
this.setSize(400, 400);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setTitle("Atom Launcher");
this.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
progressBar = new JProgressBar();
this.add(progressBar);
//this.pack();
}
public void start() {
this.setVisible(true);
}
public void close() {
this.dispose();
}
}
Class Download
package atomicElectronics.utility;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.swing.JProgressBar;
public class Download {
private static final int BUFFER_SIZE = 4096;
private JProgressBar fileProgressBar;
public Download() {
}
public void fileProgressBar(JProgressBar fileBar) {
fileProgressBar = fileBar;
}
public void exicute(String fileURL, String saveDir) throws IOException {
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();
double contentLength = httpConn.getContentLength();
if (disposition != null) {
// extracts file name from header field
int index = disposition.indexOf("filename=");
if (index > 0) {
fileName = disposition.substring(index + 9,
disposition.length());
}
} 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);
double totalRead = 0;
int bytesRead = -1;
byte[] buffer = new byte[BUFFER_SIZE];
while ((bytesRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bytesRead);
totalRead += bytesRead;
System.out.println((totalRead / contentLength) * 100);
fileProgressBar.setValue((int)((totalRead / contentLength) * 100));
}
outputStream.close();
inputStream.close();
System.out.println("File downloaded");
} else {
System.out.println("No file to download. Server replied HTTP code: " + responseCode);
}
httpConn.disconnect();
}
}
