EXAMPLES FOR DAY8 EXAMPLES

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// Project KidsDB
// Class Main

import java.sql.*;

public class Main
{
    public static void main(String[] a)
         throws ClassNotFoundException, SQLException
    {
        // Check if the JdbcOdbc driver is found in
        // the class library.  If not, throw a
        // ClassNotFoundException.  This check is
        // optional.  It is useful for debugging when
        // working with large class libraries.
        System.out.println(Class.forName(
                 "sun.jdbc.odbc.JdbcOdbcDriver"));
        System.out.println();

        // Set up string identifying the Odbc
        // entry for the database on the machine
        // where you want to access the database.
        String db = "jdbc:odbc:Kids";

        // Set up the connection to the database.
        Connection c = DriverManager.getConnection(db);

        // Set up the Statement object for the 
        // connection.  A Statement object manipulates
        // the database using SQL expressions.
        Statement s = c.createStatement();

        // A ResultSet object holds the rows in the
        // table resulting from an SQL SELECT statement.
        ResultSet r = s.executeQuery(
                            "SELECT * FROM Roster");

        // When a ResultSet object is created, the
        // cursor is positioned immediately before 
        // the first row in the result table.  
        // The method call r.next() moves the cursor 
        // to the next row in the result table.
        // r.next() returns false when it moves past
        // the end of the table.
        while (r.next())
           System.out.println(
                // r.getString(i) returns the ith
                // column of the current row of the
                // table as a string.
                r.getString(1) + " " + 
                r.getString(2) + " " +
                r.getString(3) + " " +
                r.getString(4)); 

        // Close the Connection object c when finished.
        c.close();
    }
}
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// Project KidsDB2
// Class Main

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Main
{
    public static void main(String[] a) throws 
            SQLException, ClassNotFoundException
    {
        MyFrame f = new MyFrame();
        f.show();
    }
}

************************

// Project KidsDB2
// Class MyFrame

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyFrame extends JFrame 
{
    // Instance variables.
    JTextField name, id, gender, age;
    JLabel namelabel, idlabel, genderlabel, 
                      agelabel, padlabel;
    JButton first;
    JButton next;
    boolean atEOF;
    JPanel panel;
    String db;
    Connection c;
    Statement s;
    ResultSet r;
    MyListener a;

    public MyFrame() throws SQLException,
            ClassNotFoundException
    {
        // Set caption in parent constructor.
        super("Grades");
        setSize(400, 100);

        // Allocate space for text fields.
        name = new JTextField(10);
        id = new JTextField(10);
        gender = new JTextField(10);
        age = new JTextField(10);

        // Allocate space for labels.
        namelabel = new JLabel("Name");
        idlabel = new JLabel("ID");
        genderlabel = new JLabel("Gender");
        agelabel = new JLabel("Age");
        padlabel = new JLabel("");

        first = new JButton("First Kid");
        next = new JButton("Next Kid");
        panel = new JPanel(new GridLayout(3, 4, 5, 5));
        
        atEOF = false;

        // Add controls to user interface.
        panel.add(name);
        panel.add(id);
        panel.add(gender);
        panel.add(age);
        panel.add(namelabel);
        panel.add(idlabel);
        panel.add(genderlabel);
        panel.add(agelabel);

        panel.add(padlabel);
        panel.add(first);
        panel.add(next);
        setContentPane(panel);

        // Create and add action listener.
        a = new MyListener();
        first.addActionListener(a);
        next.addActionListener(a);
        
        // Set up database stuff.
     //   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
        db = "jdbc:odbc:Kids";
        c = DriverManager.getConnection(db);
    }
       
    public class MyListener implements ActionListener
    {
        public void actionPerformed(ActionEvent event)
        {
            try
            {
                if (event.getSource() == first)
                {
                    String str = "SELECT * FROM Roster";
                    s = c.createStatement();
                    r = s.executeQuery(str);
                    atEOF = !r.next();
                    name.setText(r.getString(1));
                    id.setText(r.getString(2));
                    gender.setText(r.getString(3));
                    age.setText(r.getString(4));
                }
                else
                {
                    if (!atEOF)
                        atEOF = !r.next();

                    if (!atEOF)
                    {
                        name.setText(r.getString(1));
                        id.setText(r.getString(2));
                        gender.setText(r.getString(3));
                        age.setText(r.getString(4));
                    }
                }
            }
            catch(SQLException e)
            {
                System.out.println("SQLException");
            }
        }
    }
}

************************

// Project KidsDB3
// Class Main

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Main
{
    public static void main(String[] a) throws 
            SQLException, ClassNotFoundException
    {
        MyFrame f = new MyFrame();
        f.show();
    }
}

************************

// Class KidsDB3
// Project MyFrame

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyFrame extends JFrame 
{
    // Instance variables.
    JTextField name, id, gender, age;
    JLabel namelabel, idlabel, genderlabel, 
                      agelabel, padlabel;
    JButton first;
    JButton next;
    boolean atEOF;
    JPanel panel;
    String db;
    Connection c;
    Statement s;
    ResultSet r;
    MyListener a;

    public MyFrame() throws SQLException,
            ClassNotFoundException
    {
        // Set caption in parent constructor.
        super("Grades");
        setSize(400, 100);

        // Allocate space for text fields.
        name = new JTextField(10);
        id = new JTextField(10);
        gender = new JTextField(10);
        age = new JTextField(10);

        // Allocate space for labels.
        namelabel = new JLabel("Name");
        idlabel = new JLabel("ID");
        genderlabel = new JLabel("Gender");
        agelabel = new JLabel("Age");
        padlabel = new JLabel("");

        first = new JButton("First Kid");
        next = new JButton("Next Kid");
        panel = new JPanel(new GridLayout(3, 4, 5, 5));
        
        atEOF = false;

        // Add controls to user interface.
        panel.add(name);
        panel.add(id);
        panel.add(gender);
        panel.add(age);
        panel.add(namelabel);
        panel.add(idlabel);
        panel.add(genderlabel);
        panel.add(agelabel);

        panel.add(padlabel);
        panel.add(first);
        panel.add(next);
        setContentPane(panel);

        // Create and add action listener.
        a = new MyListener();
        first.addActionListener(a);
        next.addActionListener(a);
        
        // Set up database stuff.
     //   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
        db = "jdbc:odbc:Kids";
        c = DriverManager.getConnection(db);
    }
       
    public class MyListener implements ActionListener
    {
        public void actionPerformed(ActionEvent event)
        {
            try
            {
                if (event.getSource() == first)
                {
                    String str = 
            "SELECT * FROM Roster WHERE Name = '" +
            name.getText() + "'";
                    s = c.createStatement();
                    r = s.executeQuery(str);
                    if (atEOF = !r.next())
                        return;
                    else
                    {
                        id.setText(r.getString(2));
                        gender.setText(r.getString(3));
                        age.setText(r.getString(4));
                    }
                }
                else
                {
                    if (!atEOF)
                        atEOF = !r.next();

                    if (!atEOF)
                    {
                        id.setText(r.getString(2));
                        gender.setText(r.getString(3));
                        age.setText(r.getString(4));
                    }
                }
            }
            catch(SQLException e)
            {
                System.out.println("SQLException");
            }
        }
    }
}

************************

// Project ByGender
// Class Main

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Main
{
    public static void main(String[] a) throws 
            SQLException, ClassNotFoundException
    {
        MyFrame f = new MyFrame();
        f.show();
    }
}

************************

// Project ByGender
// Class MyFrame

import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyFrame extends JFrame 
{
    // Instance variables for controls.
    JTextArea textArea;
    JRadioButton allButton;    
    JRadioButton boysButton;
    JRadioButton girlsButton;
    ButtonGroup buttonGroup;
    JPanel panel;
    MyListener a;

    // Instance variables for database access. 
    String db;
    Connection c;
    Statement s;
    ResultSet r;

    // Miscellaneous instance variable.
    boolean atEOF;

 

    public MyFrame() throws SQLException,
            ClassNotFoundException
    {
        // Set caption in parent constructor.
        super("Grades");
        setSize(350, 300);

        // Allocate space for controls.
        allButton = new JRadioButton("All");
        boysButton = new JRadioButton("Boys");
        girlsButton = new JRadioButton("Girls");
        textArea = new JTextArea(10, 20);
        buttonGroup = new ButtonGroup();

        panel = new JPanel();
        
        atEOF = false;

        // Add radio buttons to button group.
        buttonGroup.add(allButton);
        buttonGroup.add(boysButton);
        buttonGroup.add(girlsButton);

        // Add controls to user interface.
        panel.add(allButton);
        panel.add(boysButton);
        panel.add(girlsButton);

        panel.add(textArea);
        setContentPane(panel);

        // Create and add action listener.
        a = new MyListener();
        allButton.addActionListener(a);
        boysButton.addActionListener(a);
        girlsButton.addActionListener(a);
       
        // Set up database stuff.
        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
        db = "jdbc:odbc:Kids";
        c = DriverManager.getConnection(db);
        s = c.createStatement();
    }
       
    public class MyListener implements ActionListener
    {
        public void actionPerformed(ActionEvent event)
        {
            try
            {
                if (event.getSource() == boysButton)
                {
                    String sqlStr = 
                        "SELECT * FROM Roster " +
                        "WHERE Gender = 'M'";
                    // s = c.createStatement();
                    r = s.executeQuery(sqlStr);
                    displayKids();
                }
                else if (event.getSource() == girlsButton)
                {
                    String sqlStr = 
                        "SELECT * FROM Roster " +
                        "WHERE Gender = 'F'";
                    // s = c.createStatement();
                    r = s.executeQuery(sqlStr);
                    displayKids();
                }
                else 
                {
                    String sqlStr = 
                        "SELECT * FROM Roster";
                    // s = c.createStatement();
                    r = s.executeQuery(sqlStr);
                    displayKids();
                }

            }
            catch(SQLException e)
            {
                System.out.println("SQLException");
            }
        }
    }

    private void displayKids()
    {
        try
        {
            textArea.setText("");
            while(r.next())
            {
                String str = "\n" +
                    r.getString(1) + " " +
                    r.getString(2) + " " +
                    r.getString(3) + " " +
                    r.getString(4) + " ";
                textArea.append(str);      
            }    
        }
        catch(SQLException e)
        {
            System.out.println("SQLException");
        }
    }
}

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// Project WindowClosing
// Class Main

public class Main
{
    public static void main(String[] args)
    {
        MyFrame x = new MyFrame();
        x.show();
    }
}

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// Project WindowClosing
// Class MyFrame

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JOptionPane;

public class MyFrame extends JFrame
{
    JButton closeButton;
    JPanel panel;
    MyFrame saveThis;

    public MyFrame()
    {
        super("Window Closing");
        setSize(200, 100);
        closeButton = new JButton("Close Window");
        panel = new JPanel(new FlowLayout());
        panel.add(closeButton);
        setContentPane(panel);
        saveThis = this;

        // Add WindowListener to frame.
        this.addWindowListener(new WindowCloser());

        // Add ButtonListener to button.
        closeButton.addActionListener(new ButtonListener());
    }

    private class WindowCloser implements WindowListener
    {
        // Occurs then the close button in the window
        // control box is clicked.
        public void windowClosing(WindowEvent e)
        {
            JOptionPane.showMessageDialog(saveThis,
                "Window Closed by Control Box");

		// The following line is need to close the
		// application when the window is closed.
            System.exit(0);
        }

        // Headers with empty method bodies to
        // satisfy implements WindowListener.
        // A class that implements an interface must
        // provide definitions for ALL methods in the
        // interface.
        public void windowClosed(WindowEvent e) { }
        public void windowOpened(WindowEvent e) { }
        public void windowActivated(WindowEvent e) { }
        public void windowDeactivated(WindowEvent e) { }
        public void windowDeiconified(WindowEvent e) { }
        public void windowIconified(WindowEvent e) { }
    }

    private class ButtonListener implements ActionListener
    {
        // This code is executed when the Close Window
        // button is clicked.
        public void actionPerformed(ActionEvent e)
        {
            JOptionPane.showMessageDialog(saveThis,
                "Window Closed by \"Close Window\" Button");
            dispose();
            System.exit(0);
        }
    }
}

************************

// Project WindowEvents
// Class Main

public class Main
{
    public static void main(String[] args)
    {
        MyFrame x = new MyFrame();
        x.show();
    }
}

************************

// Project WindowEvents
// Class MyFrame

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JOptionPane;

public class MyFrame extends JFrame
{
    private JTextField message;
    private JPanel panel;
    private MyFrame savedThis;
    boolean windowActivated, windowDeactivated;

    public MyFrame()
    {
        super("Window Closing");
        setSize(250, 100);
        
        message = new JTextField(15);
        panel = new JPanel();
        savedThis = this;
        windowActivated = false;
        windowDeactivated = false;

        panel.add(message);
        setContentPane(panel);

        // Add WindowListener to frame.
        this.addWindowListener(new MyWindowListener());
    }

    private class MyWindowListener 
                            implements WindowListener
    {
        // Occurs then the close button in the window
        // control box is clicked.
        public void windowClosing(WindowEvent e)
        {
            JOptionPane.showMessageDialog(savedThis,
                "Window Closing Event");
        }

        public void windowClosed(WindowEvent e)
        {
            JOptionPane.showMessageDialog(savedThis,
                "Window Closed Event");
        }

        public void windowOpened(WindowEvent e) 
        {
            JOptionPane.showMessageDialog(savedThis,
                "Window Opened Event");
        }

        public void windowActivated(WindowEvent e)  
        {
            if (!windowActivated)
            {
                message.setText(
                    "Window Activated Event");
                windowDeactivated = false;
                windowActivated = true;
            }
        }
        
        public void windowDeactivated(WindowEvent e)
        {
           if (!windowDeactivated)
           {
                message.setText(
                    "Window Deactivated Event");
                windowDeactivated = true;
                windowActivated = false;
           }
        }
        
        public void windowDeiconified(WindowEvent e) { }
        {
            JOptionPane.showMessageDialog(savedThis,
                "Window Deiconified Event");
        }
        
        public void windowIconified(WindowEvent e)
        {
            JOptionPane.showMessageDialog(savedThis,
                "Window Iconified Event");
        }
    }
}

************************

// Project MouseClicks
// Class Main

public class Main
{
    public static void main(String[] str)
    {
        MyFrame x = new MyFrame();
        x.show();
    }
}

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// Project MouseClicks
// Class MyFrame

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyFrame extends JFrame
{
    private MyPanel panel;
    
    public MyFrame()
    {
        super("Mouse Clicks");
        setSize(300, 300);
        panel = new MyPanel();
        setContentPane(panel);
    }
}

************************

// Project MouseClicks
// Class MyPanel

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class MyPanel extends JPanel
{
    private int[] x, y;
    private int nPoints;

    public MyPanel()
    {
        // x and y arrays keep track of mouse clicks.
        x = new int[100];
        y = new int[100];
        nPoints = 0;
        addMouseListener(new ClickListener());
    }

    // This method is called automatically
    // everytime part of the screen needs
    // repainting.
    public void paintComponent(Graphics g)
    {
       super.paintComponent(g);
       
       int i;
       g.setColor(Color.black);
       for(i = 0; i < nPoints; i++)
            g.fillRect(x[i] - 3, y[i] - 3, 6, 6);
   }
    
    private class ClickListener implements MouseListener
    {
        public void mouseClicked(MouseEvent e)
        {
            // The following line can be
            // used for debugging.
            // System.out.println(e);

            x[nPoints] = (int) e.getPoint().getX();
            y[nPoints] = (int) e.getPoint().getY();
            nPoints++;
            repaint();
        }

        // Method headers with empty bodies to
        // satisfy the MouseListener interface.
        public void mouseReleased(MouseEvent e) { }
        public void mousePressed(MouseEvent e) { }
        public void mouseEntered(MouseEvent e) { }
        public void mouseExited(MouseEvent e) { }
    }
}

************************


// Project ComboBox
// Class Main

public class Main
{
    public static void main(String[] args)
    {
        MyFrame x = new MyFrame();
    }
}

************************

// Project ComboBox
// Class Main

public class Main
{
    public static void main(String[] args)
    {
        MyFrame x = new MyFrame();
    }
}

************************

// Project ComboBox
// Class MyFrame

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyFrame extends JFrame
{
    JPanel panel;
    JComboBox backgroundColor;

    public MyFrame()
    {
        super("Test of JComboBox");
        setSize(300, 300);

        // Allocate space for combo box.
        backgroundColor = new JComboBox();

        panel = new JPanel();
        panel.add(backgroundColor);
        setContentPane(panel);

        // Use an action listener to detect
        // clicks on the combo box.
        backgroundColor.addActionListener(
            new ColorListener());

        // Add strings to combo box.
        backgroundColor.addItem("Black");
        backgroundColor.addItem("Blue");
        backgroundColor.addItem("Green");
        backgroundColor.addItem("Red");
        backgroundColor.addItem("White");
        backgroundColor.addItem("Yellow");

        show();
    }

    private class ColorListener 
                        implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            String color;

            // Get selected string from combo box.
            color = (String) 
                backgroundColor.getSelectedItem();

            // Set background color according to
            // selected string from combo box.
            if(color.equals("Black"))
                panel.setBackground(Color.black);
            else if(color.equals("Blue"))
                panel.setBackground(Color.blue);
            else if(color.equals("Green"))
                panel.setBackground(Color.green);
            else if(color.equals("Red"))
                panel.setBackground(Color.red);
            else if(color.equals("White"))
                panel.setBackground(Color.white);
            else if(color.equals("Yellow"))
                panel.setBackground(Color.yellow);
        }
    }
}

************************

// Project Vector
// Class Main

// Using the Java Vector collection class.

import java.util.Vector;

public class Main
{
    public static void main(String[] args)
    {
        Vector stooges;
        stooges = new Vector();

        stooges.addElement("Moe");
        stooges.addElement("Larry");
        stooges.addElement("Curly");
        stooges.addElement("Shemp");
        stooges.addElement("Joe");

        System.out.println(stooges);   
        System.out.println("Stooge #3 is " + 
            stooges.elementAt(3));
        stooges.removeElement("Shemp");
        System.out.println(stooges);   
        System.out.println();
    
        Vector kids;
        kids = new Vector();

        kids.addElement(new Kid("Jessica", 37463, 'F', 9));
        kids.addElement(new Kid("Kevin", 55986, 'M', 10));
        kids.addElement(new Kid("Katie", 86372, 'F', 11));
        kids.addElement(new Kid("William", 48347, 'M', 10));

        System.out.println(kids);
        System.out.println("Kid #2 is " + 
            kids.elementAt(2));
        Kid temp = (Kid) kids.elementAt(2);
        kids.removeElement(temp);
        System.out.println(kids);
        System.out.println();

        Vector values = new Vector();

        // Use the Integer wrapper class for adding
        // ints because only classes can be added to 
        // a Vector object.
        values.addElement(new Integer(43));
        values.addElement(new Integer(97));
        values.addElement(new Integer(28));
        values.addElement(new Integer(13));
        values.addElement(new Integer(77));

        System.out.println(values);
        System.out.println("Value #4 is " + values.elementAt(4));
        Object x = values.elementAt(4);
        values.removeElement(x);
        System.out.println(values);
        System.out.println();
    }
}

************************

// Vector Project
// Class Kid

public class Kid
{
    // Private instance variables.
    private String name;
    private int id;
    private char gender;
    private short age;

    // Default constructor.
    public Kid()
    {
        // Initialize to default values.
        name = "Unknown";
        id = 99999;
        gender = 'U';
        age = -1;
    }

    // Parameterized constructor.
    public Kid(String aName, int anId, char aGender, int anAge)
    {
        // name is not the null string.
        if (aName.equals(""))
            name = "Unknown";
        else
            name = aName;

        // id is between 0 and 99999.
        if (anId < 0 || anId > 99998)
            id = 99999;
        else
            id = anId;

        // Gender is 'F', 'M', or 'U'.
        if (aGender != 'F' && aGender != 'M')
            gender = 'U';
        else
            gender = aGender;

        // Age is nonnegative.
        if (anAge < 0)
            age = (short) -1;
        age = (short) anAge;
    }

    // Accessor method for name.
    public String getName()
    {
        return name;
    }

   // Accessor method for id.
    public int getId()
    {
        return id;
    }   

    // Accessor method for gender.
    public char getGender()
    {
        return gender;
    }

    // Accessor method for age.
    public short getAge()
    {
        return (short) age;
    }

    // Mutator method for age.
    public void hasBirthday()
    {
        age++;
    }

    // Print method.
    public void print()
    {
        System.out.print("name=" + name + " " );
        System.out.print("id=" + id + " " );
        System.out.print("gender=" + gender + " ");
        System.out.println("age=" + age + '\n');
    }

    public String toString()
    {
        return "<" + name + ";" + id + ";" +
                     gender + ";" + age + ">";
    }
}

************************

// Project Recursive
// Class Main

// Practice problem: predict the output by first
// drawing the recursion tree.

public class Main
{
    public static void main(String[] args)
    {
        f(3);
    }

    public static void f(int n)
    {
        if (n > 0)
        {
            System.out.print(n + " ");
            f(n - 1);
            System.out.print(n + " ");
            f(n - 2);
            System.out.print((n + 1) + " ");
        }
    }
}

************************

// Project FamilyTree
// Class Main

import java.util.Vector;

public class Main
{
    public static void main(String[] args)
    {
        Person root = new Person("John");
        Person temp;

        // Add children of John.
        root.children.addElement(new Person("Mary"));
        root.children.addElement(new Person("William"));
        root.children.addElement(new Person("Agnes"));

        // Add children of Mary
        ((Person) root.children.elementAt(0)).children.
            addElement(new Person("Tamera"));
        ((Person) root.children.elementAt(0)).children.
            addElement(new Person("Scott"));

        // Add children of William
        temp = (Person) (root.children.elementAt(1));
        temp.children.addElement(new Person("Susan"));
        temp.children.addElement(new Person("Jerry"));

        // Add child of Agnes.
        temp = (Person) (root.children.elementAt(2));
        temp.children.addElement(new Person("Winston"));
 
        // Add child of Susan.
        temp = (Person) ((Person) (root.children.elementAt(1))).
            children.elementAt(0);
        temp.children.addElement(new Person("Brittany"));

        root.print();
    }
}

************************

// Project FamilyTree
// Class Person

import java.util.Vector;

public class Person
{
    public String name;
    public Vector children;

    public Person(String aName)
    {
        name = aName;
        children = new Vector();
    }

    // Recursive print routine.
    public void print()
    {
        int i;
        System.out.println(name);
        for(i = 0; i < children.size(); i++)
            ((Person) (children.elementAt(i))).print();
    }
}

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