// A class for loading pages into the WWW browser.
// Barry Cornelius, 13th February 2000
import java.awt.event. ActionEvent;
import java.awt.event. ActionListener;
import java.util. ArrayList;
import java.io. IOException;
import java.util. Iterator;
import javax.swing. JEditorPane;
import javax.swing. JTextField;
import java.util. List;
public class PagesHandler implements ActionListener
{
private List iHistory;
private JEditorPane iJEditorPane;
private JTextField iURLJTextField;
private void iOutputHistory()
{
iURLJTextField.setText("");
final StringBuffer tStringBuffer = new StringBuffer();
tStringBuffer.append("");
int tURLNumber = 0;
final Iterator tIterator = iHistory.iterator();
while (tIterator.hasNext())
{
tURLNumber++;
tStringBuffer.append("| " + tURLNumber + " | " +
tIterator.next() + " |
");
}
tStringBuffer.append("
\n");
iJEditorPane.setContentType("text/html");
iJEditorPane.setText("" + tStringBuffer);
}
private String iGetURLFromHistory(int pURLNumber)
{
final boolean tAdd = pURLNumber>=0;
pURLNumber = Math.abs(pURLNumber);
if (pURLNumber==0 || pURLNumber>iHistory.size())
{
return "";
}
// pURLNumber>=1 && pURLNumber<=iHistory.size()
if (tAdd)
{
return (String)iHistory.get(pURLNumber - 1);
}
iHistory.remove(pURLNumber - 1);
return "";
}
public PagesHandler(final JEditorPane pJEditorPane,
final JTextField pURLJTextField)
{
iHistory = new ArrayList();
iJEditorPane = pJEditorPane;
iURLJTextField = pURLJTextField;
}
public void actionPerformed(final ActionEvent pActionEvent)
{
iOutputHistory();
}
public void setPage(String pURLString)
{
if (pURLString==null || pURLString.equals(""))
{
iOutputHistory();
return;
}
final char tFirstChar = pURLString.charAt(0);
int tURLNumber = 0;
if ( tFirstChar=='-' || Character.isDigit(tFirstChar))
{
try
{
tURLNumber = Integer.parseInt(pURLString);
}
catch(final NumberFormatException pNumberFormatException)
{
tURLNumber = 0;
}
pURLString = iGetURLFromHistory(tURLNumber);
}
if (pURLString.equals(""))
{
iOutputHistory();
return;
}
try
{
iURLJTextField.setText(pURLString);
// The setPage call (below) will change the ContentType to text/html.
// This seemingly nonsensical call of setContentType ensures that
// setPage reloads the WWW page even if it is already loaded.
iJEditorPane.setContentType("text/plain");
iJEditorPane.setPage(pURLString);
if ( ! iHistory.contains(pURLString) )
{
iHistory.add(pURLString);
}
}
catch(IOException pIOException)
{
iJEditorPane.setContentType("text/html");
iJEditorPane.setText("" +
"" +
"error in URL
" +
"" +
"\n");
}
}
}