LoginUI.java

package ua.vntu.amon.gui;

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.IOException;
import java.util.ArrayList;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

import ua.vntu.amon.provider.zabbix.ZabbixClient;

public class LoginUI extends JFrame {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	ZabbixClient client = new ZabbixClient();

	ArrayList<String> host = new ArrayList<>();

	public LoginUI() {
		setTitle("Login Form");
		getContentPane().setLayout(new FlowLayout());
		setSize(500, 250);
		setResizable(false);
		setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);

		/* GUI Panels */
		JPanel informationPanel = new JPanel(new GridLayout(3, 2));
		JPanel buttonPanel = new JPanel(new GridLayout(1, 2));
		JPanel errorPanel = new JPanel(new GridLayout(1, 1));

		/* Text Font */
		Font errorFont = new Font("Verdana", Font.BOLD, 14);
		Font simpleFont = new Font("Verdana", Font.PLAIN, 14);

		/* Label */
		final JLabel serverIpLabel = createLabel("Server Ip Address", "IP.jpg",
				simpleFont, true);
		final JLabel userNameLabel = createLabel("Login Name",
				"login_name.png", simpleFont, true);
		final JLabel passwordLabel = createLabel("Password", "password.png",
				simpleFont, true);
		final JLabel errorLabel = createLabel("", "network-error.png",
				errorFont, false);
		errorLabel.setForeground(Color.RED);
		/* TextField */
		final JTextField userNameTextField = new JTextField(20);
		userNameTextField.setText("admin");
		userNameTextField.setToolTipText("Enter your register user name");

		final JPasswordField passwordField = new JPasswordField(20);
		passwordField.setText("zabbix");
		passwordField.setToolTipText("Enter your password ");

		final JTextField serverIpTextField = new JTextField();
		serverIpTextField.setText("http://192.168.56.101");
		serverIpTextField
				.setToolTipText("Enter IP address of Zabbix server, such as 'http://192.168.56.101/api_jsonrpc.php' ");

		/* Buttons */
		JButton submitButton = createButton("Log In",
				"Press to login in network monitoring program", "login.png",
				simpleFont, new ActionListener() {
					@Override
					public void actionPerformed(ActionEvent e) {
						// TODO Auto-generated method stub
						String name = userNameTextField.getText();
						@SuppressWarnings("deprecation")
						String password = passwordField.getText();
						String url = serverIpTextField.getText();

						if ((name.equals("")) || password.equals("")
								|| serverIpTextField.equals("")) {
							errorLabel.setText("One of the fields is empty !!");
							errorLabel.setVisible(true);
						} else {
							try {
								client.setUrl(url);
								client.register(name, password);
								if (client.getTokenSession() != null) {
									// create Gui
									new MainUI(name, password, url).setVisible(true);
									setVisible(false);
								} else {
									errorLabel
											.setText("Login name  or password is incorrect !!");
									errorLabel.setVisible(true);
								}
							} catch (Exception e1) {
								// e1.printStackTrace();
								errorLabel.setText("HTTP 404 - Not Found ");
								errorLabel.setVisible(true);
							}
						}
					}
				});

		JButton resetButton = createButton("Reset",
				"Press to clean all fields", "reset.png", simpleFont,
				new ActionListener() {

					@Override
					public void actionPerformed(ActionEvent arg0) {
						// TODO Auto-generated method stub
						userNameTextField.setText("");
						passwordField.setText("");
						errorLabel.setVisible(false);
						serverIpTextField.setText("");
					}
				});

		/* Add components to Panels */
		informationPanel.add(serverIpLabel);
		informationPanel.add(serverIpTextField);
		informationPanel.add(userNameLabel);
		informationPanel.add(userNameTextField);
		informationPanel.add(passwordLabel);
		informationPanel.add(passwordField);

		buttonPanel.add(submitButton);
		buttonPanel.add(resetButton);
		errorPanel.add(errorLabel);

		getContentPane().add(errorPanel);
		getContentPane().add(informationPanel);
		getContentPane().add(buttonPanel);

		addWindowListener(new WindowAdapter() {
			public void windowClosing(WindowEvent we) {
				int value = JOptionPane.showConfirmDialog(null,
						"Are you sure you want to close Login Form?", "Close",
						JOptionPane.YES_NO_OPTION, JOptionPane.ERROR_MESSAGE);
				if (value == 0) {
					System.exit(0);
				} else {
					setVisible(true);
				}
			}
		});
		setVisible(true);
	}

	private JButton createButton(String title, String toolTip, String path,
			Font font, ActionListener listener) {
		JButton button = new JButton(title);
		button.setToolTipText(toolTip);
		try {
			Image img = ImageIO.read(getClass().getResourceAsStream(
					"/resources/" + path));
			button.setIcon(new ImageIcon(img));
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		button.setFont(font);
		button.addActionListener(listener);
		return button;
	}

	private JLabel createLabel(String title, String path, Font font,
			Boolean visible) {
		JLabel label = new JLabel(title);
		label.setVisible(visible);
		label.setFont(font);
		try {
			Image img = ImageIO.read(getClass().getResourceAsStream(
					"/resources/" + path));
			label.setIcon(new ImageIcon(img));
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		return label;
	}

	public static void main(String args[]) throws Exception {
		SwingUtilities.invokeLater(new Runnable() {
			public void run() {
				new LoginUI();
			}
		});
	}
}