Source Code : Make your own Java Download Manager

Make your own Java Download Manager

Source Code

<code> 
import java.awt.BorderLayout; 
import java.awt.Component; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.awt.event.KeyEvent; 
import java.awt.event.WindowAdapter; 
import java.awt.event.WindowEvent; 
import java.io.File; 
import java.io.FileOutputStream; 
import java.io.InputStream; 
import java.io.RandomAccessFile; 
import java.net.HttpURLConnection; 
import java.net.URL; 
import java.util.ArrayList; 
import java.util.Observable; 
import java.util.Observer; 
import java.util.Properties;
import javax.swing.BorderFactory; 
import javax.swing.JButton; 
import javax.swing.JFileChooser; 
import javax.swing.JFrame; 
import javax.swing.JLabel; 
import javax.swing.JMenu; 
import javax.swing.JMenuBar; 
import javax.swing.JMenuItem; 
import javax.swing.JOptionPane; 
import javax.swing.JPanel; 
import javax.swing.JProgressBar; 
import javax.swing.JScrollPane; 
import javax.swing.JTable; 
import javax.swing.JTextField; 
import javax.swing.ListSelectionModel; 
import javax.swing.event.ListSelectionEvent; 
import javax.swing.event.ListSelectionListener; 
import javax.swing.table.AbstractTableModel; 
import javax.swing.table.TableCellRenderer;
public class DownloadManager extends JFrame implements Observer { 
private JTextField addTextField = new JTextField(30);
 private DownloadsTableModel tableModel = new DownloadsTableModel();
 private JTable table;
 private JButton pauseButton = new JButton("Pause");
 private JButton resumeButton = new JButton("Resume");
 private JButton cancelButton, clearButton;
 private JLabel saveFileLabel = new JLabel();
 private Download selectedDownload;
 private boolean clearing;
 public DownloadManager() { 
setTitle("Marvin's Download Manager"); 
setSize(640, 480); 
addWindowListener(new WindowAdapter() { 
public void windowClosing(WindowEvent e) { 
System.exit(0); 
} 
}); 
JMenuBar menuBar = new JMenuBar(); 
JMenu fileMenu = new JMenu("File"); 
fileMenu.setMnemonic(KeyEvent.VK_F); 
JMenuItem fileExitMenuItem = new JMenuItem("Exit", KeyEvent.VK_X); 
fileExitMenuItem.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
System.exit(0); 
} 
}); 
fileMenu.add(fileExitMenuItem); 
menuBar.add(fileMenu); 
setJMenuBar(menuBar);
 // Set up add panel. 
JPanel addPanel = new JPanel(new BorderLayout());
 JPanel targetPanel = new JPanel(new BorderLayout()); 
targetPanel.add(addTextField, BorderLayout.WEST); 
JButton addButton = new JButton("Add Download"); 
addButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionAdd(); 
} 
});
 targetPanel.add(addButton, BorderLayout.EAST);
 JPanel destinationPanel = new JPanel(new BorderLayout()); 
saveFileLabel.setText("File:"); 
destinationPanel.add(saveFileLabel, BorderLayout.WEST);
 JButton saveFileButton = new JButton("Download To"); 
saveFileButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionSaveTo(); 
} 
}); 
destinationPanel.add(saveFileButton, BorderLayout.EAST); 
addPanel.add(destinationPanel, BorderLayout.NORTH); 
addPanel.add(targetPanel, BorderLayout.SOUTH);
 // Set up Downloads table. 
 
table = new JTable(tableModel); 
table.getSelectionModel().addListSelectionListener(new ListSelectionListener() { 
public void valueChanged(ListSelectionEvent e) { 
tableSelectionChanged(); 
} 
}); 
table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
 ProgressRenderer renderer = new ProgressRenderer(0, 100); 
renderer.setStringPainted(true); // show progress text 
table.setDefaultRenderer(JProgressBar.class, renderer);
 table.setRowHeight((int) renderer.getPreferredSize().getHeight());
 JPanel downloadsPanel = new JPanel(); 
downloadsPanel.setBorder(BorderFactory.createTitledBorder("Downloads")); 
downloadsPanel.setLayout(new BorderLayout()); 
downloadsPanel.add(new JScrollPane(table), BorderLayout.CENTER);
 JPanel buttonsPanel = new JPanel();
 pauseButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionPause(); 
} 
}); 
pauseButton.setEnabled(false); 
buttonsPanel.add(pauseButton);
 resumeButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionResume(); 
} 
}); 
resumeButton.setEnabled(false); 
buttonsPanel.add(resumeButton); 
cancelButton = new JButton("Cancel"); 
cancelButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionCancel(); 
} 
}); 
cancelButton.setEnabled(false); 
buttonsPanel.add(cancelButton); 
clearButton = new JButton("Clear"); 
clearButton.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
actionClear(); 
} 
}); 
clearButton.setEnabled(false); 
buttonsPanel.add(clearButton);
 getContentPane().setLayout(new BorderLayout()); 
getContentPane().add(addPanel, BorderLayout.NORTH); 
getContentPane().add(downloadsPanel, BorderLayout.CENTER); 
getContentPane().add(buttonsPanel, BorderLayout.SOUTH); 
}
 private void actionSaveTo() 
{
 JFileChooser jfchooser = new JFileChooser();
 jfchooser.setApproveButtonText("OK"); 
jfchooser.setDialogTitle("Save To"); 
jfchooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
 int result = jfchooser.showOpenDialog(this); 
File newZipFile = jfchooser.getSelectedFile(); 
System.out.println("importProfile:" + newZipFile); 
this.saveFileLabel.setText(newZipFile.getPath()); }
 private void actionAdd() { 
URL verifiedUrl = verifyUrl(addTextField.getText()); 
if (verifiedUrl != null) { 
tableModel.addDownload(new Download(verifiedUrl, saveFileLabel.getText())); 
addTextField.setText(""); // reset add text field 
 } else { 
JOptionPane.showMessageDialog(this, "Invalid Download URL", "Error", 
JOptionPane.ERROR_MESSAGE); 
} 
}
 private URL verifyUrl(String url) { 
if (!url.toLowerCase().startsWith("http://")) 
return null;
 URL verifiedUrl = null; 
try { 
verifiedUrl = new URL(url); 
} catch (Exception e) { 
return null; 
}
 if (verifiedUrl.getFile().length() < 2) 
return null;
 return verifiedUrl; 
}
 private void tableSelectionChanged() { 
if (selectedDownload != null) 
selectedDownload.deleteObserver(DownloadManager.this);
 if (!clearing && table.getSelectedRow() > -1) { 
selectedDownload = tableModel.getDownload(table.getSelectedRow()); 
selectedDownload.addObserver(DownloadManager.this); 
updateButtons(); 
} 
}
 private void actionPause() { 
selectedDownload.pause(); 
updateButtons(); 
}
 private void actionResume() { 
selectedDownload.resume(); 
updateButtons(); 
}
 private void actionCancel() { 
selectedDownload.cancel(); 
updateButtons(); 
}
 private void actionClear() { 
clearing = true; 
tableModel.clearDownload(table.getSelectedRow()); 
clearing = false; 
selectedDownload = null; 
updateButtons(); 
}
 private void updateButtons() { 
if (selectedDownload != null) { 
int status = selectedDownload.getStatus(); 
switch (status) { 
case Download.DOWNLOADING: 
pauseButton.setEnabled(true); 
resumeButton.setEnabled(false); 
cancelButton.setEnabled(true); 
clearButton.setEnabled(false); 
break; 
case Download.PAUSED: 
pauseButton.setEnabled(false); 
resumeButton.setEnabled(true); 
cancelButton.setEnabled(true); 
clearButton.setEnabled(false); 
break; 
case Download.ERROR: 
pauseButton.setEnabled(false); 
resumeButton.setEnabled(true); 
cancelButton.setEnabled(false); 
clearButton.setEnabled(true); 
break; 
default: // COMPLETE or CANCELLED 
pauseButton.setEnabled(false); 
resumeButton.setEnabled(false); 
cancelButton.setEnabled(false); 
clearButton.setEnabled(true); 
} 
} else { 
pauseButton.setEnabled(false); 
resumeButton.setEnabled(false); 
cancelButton.setEnabled(false); 
clearButton.setEnabled(false); 
} 
}
 public void update(Observable o, Object arg) { 
// Update buttons if the selected download has changed. 
if (selectedDownload != null && selectedDownload.equals(o)) 
updateButtons(); 
}
 // Run the Download Manager. 
public static void main(String[] args) { 
DownloadManager manager = new DownloadManager(); 
manager.setVisible(true); 
} 
}
class Download extends Observable implements Runnable { 
private static final int MAX_BUFFER_SIZE = 1024;
 public static final String STATUSES[] = { "Downloading", "Paused", "Complete", "Cancelled", 
"Error" };
 public static final int DOWNLOADING = 0;
 public static final int PAUSED = 1;
 public static final int COMPLETE = 2;
 public static final int CANCELLED = 3;
 public static final int ERROR = 4;
 private URL url; // download URL 
 
private String saveDir; // dir to save 
 
private int size; // size of download in bytes 
 
private int downloaded; // number of bytes downloaded 
 
private int status; // current status of download
 // Proxy information 
public static final boolean proxyRequired = true; // Change for your settings 
public static final String proxyIP = "127.0.0.1"; 
public static final String proxyPort = "8080"; 
public static final String proxyUsername = "proxyUser"; 
public static final String proxyPassword = "proxyPassword";
 // Constructor for Download. 
public Download(URL url, String saveDir) { 
this.url = url; 
this.saveDir = saveDir; 
size = -1; 
downloaded = 0; 
status = DOWNLOADING;
 // Begin the download. 
download(); 
}
 // Get this download's URL. 
public String getUrl() { 
return url.toString(); 
}
 // Get this download's size. 
public int getSize() { 
return size; 
}
 // Get this download's progress. 
public float getProgress() { 
return ((float) downloaded / size) * 100; 
}
 public int getStatus() { 
return status; 
}
 public void pause() { 
status = PAUSED; 
stateChanged(); 
}
 public void resume() { 
status = DOWNLOADING; 
stateChanged(); 
download(); 
}
 public void cancel() { 
status = CANCELLED; 
stateChanged(); 
}
 private void error() { 
status = ERROR; 
stateChanged(); 
}
 private void download() { 
Thread thread = new Thread(this); 
thread.start(); 
}
 // Get file name portion of URL. 
public String getFileName(URL url) { 
String fileName = url.getFile(); 
return fileName.substring(fileName.lastIndexOf('/') + 1); 
}
 // Download file. 
public void run() { 
RandomAccessFile file = null; 
InputStream stream = null; 
FileOutputStream out = null;
 try {
 if (proxyRequired){ 
// This can be put in a menu, updated via interface 
System.out.println("Setting proxy"); 
Properties systemSettings = System.getProperties(); 
systemSettings.put("http.proxyHost", proxyIP); 
systemSettings.put("http.proxyPort", proxyPort); 
System.setProperties(systemSettings); 
}
 // Open connection to URL. 
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
 // Specify what portion of file to download. 
connection.setRequestProperty("Range", "bytes=" + downloaded + "-");
 if (proxyRequired){ 
String encoded = new String(new sun.misc.BASE64Encoder().encode(new String( proxyUsername + ":" + proxyPassword).getBytes())); 
connection.setRequestProperty("Proxy-Authorization", "Basic " + encoded); 
}
 System.out.println("Going to make connection"); 
// Connect to server. 
connection.connect(); 
System.out.println("Connected!");
 int responseCode = connection.getResponseCode(); 
System.out.println("Response code from server=" + responseCode);
 // Make sure response code is in the 200 range. 
// 200 - no partial download 
// 206 - supports resume 
//if (responseCode / 100 != 2) { 
if (responseCode == 200 || responseCode == 206) { 
error(); 
}
 // Check for valid content length. 
System.out.println("Content length=" + connection.getContentLength()); 
int contentLength = connection.getContentLength(); 
if (contentLength < 1) { 
error(); 
}
 /* 
* Set the size for this download if it hasn't been already set. 
*/ 
if (size == -1) { 
size = contentLength; 
stateChanged(); 
}
 // Open file and seek to the end of it. 
file = new RandomAccessFile(getFileName(url), "rw"); 
file.seek(downloaded);
 System.out.println("Get InputStream"); 
stream = connection.getInputStream(); 
status = DOWNLOADING; 
out = new FileOutputStream(saveDir + File.separator + this.getFileName(url)); 
while (status == DOWNLOADING) { 
/* 
* Size buffer according to how much of the file is left to download. 
*/ 
byte buffer[]; 
if (size - downloaded > MAX_BUFFER_SIZE) { 
buffer = new byte[MAX_BUFFER_SIZE]; 
} else { 
buffer = new byte[size - downloaded]; 
}
 // Read from server into buffer. 
int read = stream.read(buffer); 
if (read == -1) 
break;
 // Write buffer to file. 
//file.write(buffer, 0, read); 
out.write(buffer, 0, read); 
downloaded += read; 
stateChanged(); 
}
 /* 
* Change status to complete if this point was reached because downloading 
* has finished. 
*/ 
if (status == DOWNLOADING) { 
status = COMPLETE;
 stateChanged(); 
} 
} catch (Exception e) { 
System.out.println("Error=" + e); 
e.printStackTrace(); 
error(); 
} finally {
 // Close file. 
if (file != null) { 
try { 
// Complete the file 
out.close(); 
file.close(); 
} catch (Exception e) { 
e.printStackTrace(); 
} 
}
 // Close connection to server. 
if (stream != null) { 
try { 
stream.close(); 
} catch (Exception e) { 
e.printStackTrace(); 
} 
} 
} 
}
 private void stateChanged() { 
setChanged(); 
notifyObservers(); 
} 
}
class DownloadsTableModel extends AbstractTableModel implements Observer { 
private static final String[] columnNames = { "URL", "Size", "Progress", "Status" };
 private static final Class[] columnClasses = { String.class, String.class, JProgressBar.class, 
String.class };
 private ArrayList<Download> downloadList = new ArrayList<Download>();
 public void addDownload(Download download) { 
download.addObserver(this); 
downloadList.add(download); 
fireTableRowsInserted(getRowCount() - 1, getRowCount() - 1); 
}
 public Download getDownload(int row) { 
return (Download) downloadList.get(row); 
}
 public void clearDownload(int row) { 
downloadList.remove(row); 
fireTableRowsDeleted(row, row); 
}
 public int getColumnCount() { 
return columnNames.length; 
}
 public String getColumnName(int col) { 
return columnNames[col]; 
}
 public Class getColumnClass(int col) { 
return columnClasses[col]; 
}
 public int getRowCount() { 
return downloadList.size(); 
}
 public Object getValueAt(int row, int col) { 
Download download = downloadList.get(row); 
switch (col) { 
case 0: // URL 
return download.getUrl(); 
case 1: // Size 
int size = download.getSize(); 
return (size == -1) ? "" : Integer.toString(size); 
case 2: // Progress 
return new Float(download.getProgress()); 
case 3: // Status 
return Download.STATUSES[download.getStatus()]; 
} 
return ""; 
}
 public void update(Observable o, Object arg) { 
int index = downloadList.indexOf(o); 
fireTableRowsUpdated(index, index); 
} 
}
class ProgressRenderer extends JProgressBar implements TableCellRenderer { 
public ProgressRenderer(int min, int max) { 
super(min, max); 
}
 public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, 
boolean hasFocus, int row, int column) { 
setValue((int) ((Float) value).floatValue()); 
return this; 
}</code><code>}</code>

Source Code : Make your own Java Download Manager

Make your own Java Download Manager

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