Closed. This question is off-topic。它当前不接受答案。
想改善这个问题吗? Update the question,所以它是on-topic,用于堆栈溢出。
4年前关闭。
我是网络编程的新手。
这是我的代码:
我正在从IDE运行此代码。问题是虽然我打开了带有URL的流,但没有调用
请帮忙。
提前致谢
想改善这个问题吗? Update the question,所以它是on-topic,用于堆栈溢出。
4年前关闭。
我是网络编程的新手。
这是我的代码:
public class ComputerNetworks extends Authenticator {
private JDialog passwordDialog;
private JLabel mainLabel= new JLabel("Please enter username and password: ");
private JLabel userLabel = new JLabel("Username: ");
private JLabel passwordLabel = new JLabel("Password: ");
private JTextField usernameField = new JTextField(20);
private JPasswordField passwordField = new JPasswordField(20);
private JButton okButton = new JButton("OK");
private JButton cancelButton = new JButton("Cancel");
public ComputerNetworks( ) {
this("", new JFrame());
}
public ComputerNetworks(String username) {
this(username, new JFrame());
}
public ComputerNetworks(JFrame parent) {
this("", parent);
}
public ComputerNetworks(String username, JFrame parent) {
this.passwordDialog = new JDialog(parent, true);
Container pane = passwordDialog.getContentPane( );
pane.setLayout(new GridLayout(4, 1));
pane.add(mainLabel);
JPanel p2 = new JPanel( );
p2.add(userLabel);
p2.add(usernameField);
usernameField.setText(username);
pane.add(p2);
JPanel p3 = new JPanel( );
p3.add(passwordLabel);
p3.add(passwordField);
pane.add(p3);
JPanel p4 = new JPanel( );
p4.add(okButton);
p4.add(cancelButton);
pane.add(p4);
ActionListener al = new OKResponse( );
okButton.addActionListener(al);
usernameField.addActionListener(al);
passwordField.addActionListener(al);
cancelButton.addActionListener(new CancelResponse( ));
passwordDialog.pack( );
passwordDialog.setVisible(true);
}
private void show( ) {
String prompt = this.getRequestingPrompt( );
if (prompt == null) {
String site = this.getRequestingSite().getHostName( );
String protocol = this.getRequestingProtocol( );
int port = this.getRequestingPort();
if (site != null & protocol != null) {
prompt = protocol + "://" + site;
if (port > 0)
prompt += ":" + port;
} else {
prompt = "";
}
}
mainLabel.setText("Please enter username and password for "
+ prompt + ": ");
passwordDialog.pack();
passwordDialog.setVisible(true);
}
PasswordAuthentication response = null;
class OKResponse implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
System.out.println("OK clicked");
passwordDialog.setVisible(false);
// The password is returned as an array of
// chars for security reasons.
char[] password = passwordField.getPassword( );
String username = usernameField.getText( );
// Erase the password in case this is used again.
passwordField.setText("");
response = new PasswordAuthentication(username, password);
}
}
class CancelResponse implements ActionListener {
public void actionPerformed(ActionEvent e) {
passwordDialog.hide( );
// Erase the password in case this is used again.
passwordField.setText("");
response = null;
}
}
public PasswordAuthentication getPasswordAuthentication( ) {
this.show();
return this.response;
}
public static void main(String[] args) throws Exception {
Authenticator.setDefault(new ComputerNetworks());
URL u = new URL("http://www.google.co.in");
InputStream in = u.openStream();
}
}
我正在从IDE运行此代码。问题是虽然我打开了带有URL的流,但没有调用
getPasswordAuthentication()
的Authenticator
方法。请帮忙。
提前致谢
最佳答案
从JavaDoc:
getPasswordAuthentication()
protected PasswordAuthentication getPasswordAuthentication()
需要密码授权时调用。子类应覆盖默认实现,该实现返回null。
返回值:
从用户收集的PasswordAuthentication,如果未提供,则为null。
就我所知,google.co.in不需要密码授权。因此,不使用Authenticator
。尝试输入确实需要身份验证的URL,然后查看是否有帮助。
09-29 21:52