esercizio Database

Esempio di progettazione di un database.

Esercizio con Java 4-05-09

ESERCIZIO CALCOLATRICE
Lunedi 9 Febbraio 2009

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

public class Calcolatrice{

JFrame f=new JFrame("Calcolatrice");
JLabel l1=new JLabel("primo numero");
JLabel l2=new JLabel("secondo numero");
JTextField f1=new JTextField();
JTextField f2=new JTextField();
JButton b1=new JButton("Somma");
JButton b2=new JButton("Sottrazione");
JButton b3=new JButton("Moltiplicazione");
JButton b4=new JButton("Divisione");
JTextField risultato=new JTextField();

public Calcolatrice(){
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(400,400);
f.setLayout(new GridLayout(5,8));
f.add(l1);
f.add(f1);
f.add(l2);
f.add(f2);
f.add(b1);
f.add(b2);
f.add(b3);
f.add(b4);
f.add(risultato);
b1.addActionListener(new Somma());
f.setVisible(true);
b2.addActionListener(new Sottrazione());
f.setVisible(true);
b3.addActionListener(new Moltiplicazione());
f.setVisible(true);
b4.addActionListener(new Divisione());
f.setVisible(true);
}
public class Somma implements ActionListener{
public void actionPerformed(ActionEvent e){
String testo1=f1.getText();
String testo2=f2.getText();
int t=Integer.parseInt(testo1);
int t1=Integer.parseInt(testo2);
double somma=t+t1;
String r=Double.toString(Somma);
risultato.setText(r);
}
}
public class Sottrazione implements ActionListener{
public void actionPerformed(ActionEvent e){
String testo1=f1.getText();
String testo2=f2.getText();
int t=Integer.parseInt(testo1);
int t1=Integer.parseInt(testo2);
double sottrazione=t-t1;
String r=Double.toString(Sottrazione);
risultato.setText(r);
}
}
public class Moltiplicazione implements ActionListener{
public void actionPerformed(ActionEvent e){
String testo1=f1.getText();
String testo2=f2.getText();
int t=Integer.parseInt(testo1);
int t1=Integer.parseInt(testo2);
int moltiplicazione=t*t1;
String r=Integer.toString(Moltiplicazione);
risultato.setText(r);
}
}
public class Divisione implements ActionListener{
public void actionPerformed(ActionEvent e){
String testo1=f1.getText();
String testo2=f2.getText();
int t=Integer.parseInt(testo1);
int t1=Integer.parseInt(testo2);
double divisione=t/t1;
String r=Double.toString(Divisione);
risultato.setText(r);
}
}
public static void main (String []args){
Calcolatrice f=new Calcolatrice();
}
}

Esercitazione 12-12-2008

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Grafica1 {
private JFrame f;
private Pannello1 p;
private JButton b1;
public Grafica1(){
f=new JFrame("prova pannello");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(300,300);
b1=new JButton("cambia clolore casuale");
f.setLayout(new GridLayout(2,1));
p=new Pannello1();
f.add(b1);
f.add(p);
f.setVisible(true);
}
public class Pannello1 extends JPanel {
public void paintComponent(Graphics g){
Graphics2D g2D=(Graphics2D) g;
int verde=(int) (Math.random()*255);
int rosso=(int) (Math.random()*255);
int blu=(int) (Math.random()*255);
Color colore=new Color(rosso,verde,blu);
g2D.setColor(colore);
g2D.fillOval(0,0,70,70);
}
}
public static void main(String[] args){
Grafica1 g1=new Grafica1();
}
}

Calcolatrice

Esercitazione a scuola...

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Finestra2 implements ActionListener{
JLabel l1=new JLabel("primo numero");
JLabel l2=new JLabel("secondo numero");
JTextField t1=new JTextField();
JTextField t2=new JTextField();
JButton b1=new JButton("+");
JTextField risultato=new JTextField();
public void creaForm1(){
JFrame finestra1=new JFrame("finestra IVL");
finestra1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
finestra1.setSize(300,300);
finestra1.setLayout(new GridLayout(3,2));
finestra1.add(l1);
finestra1.add(t1);
finestra1.add(l2);
finestra1.add(t2);
finestra1.add(b1);
finestra1.add(risultato);
b1.addActionListener(this);
finestra1.setVisible(true);
}
public void actionPerformed(ActionEvent event){
String testo1=t1.getText();
String testo2=t2.getText();
int a=Integer.parseInt(testo1);
int b=Integer.parseInt(testo2);
int somma=a+b;
String r=Integer.toString(somma);
risultato.setText(r);
}
}

Finestra in java...Esercitazione 1-12-08

import javax.swing.*;
public class Finestra1 {
public void creaForm1(){
JFrame finestra1=new JFrame("finestra IVL");
finestra1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
finestra1.setSize(300,300);
finestra1.setVisible(true);
}
}

public class TestaFinestra{
public static void main(String[] args){
Finestra1 f=new Finestra1();
f.creaForm1();
}
}

Esercitazione Lunedi 24 Novembre

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.util.*;
import java.awt.geom.*;
public class RotazionePoligono extends Applet implements MouseListener, KeyListener{
private int[] xpoints={0,-10,-7,7,10};
private int[] ypoints={-10,-2,10,10,-2};
private Polygon poly;

int rotation=0;
public void init(){
poly=new Polygon (xpoints,ypoints,xpoints.length);
addMouseListener(this);
addKeyListener(this);
}
public void paint (Graphics g){
Graphics2D g2D=(Graphics2D) g;
int ampiezza=getSize().width;
int altezza=getSize().height;
g2D.setColor(Color.YELLOW);
g2D.fillRect(0,0,ampiezza,altezza);
g2D.translate(ampiezza/2,altezza/2);
g2D.scale(20,20);
g2D.rotate(Math.toRadians(rotation));
g2D.setColor(Color.RED);
g2D.draw(poly);
g2D.setColor(Color.BLUE);
g2D.fill(poly);
}
public void mouseEntered(MouseEvent m){}
public void mouseExited(MouseEvent m){}
public void mouseReleased(MouseEvent m){}
public void mouseClicked(MouseEvent m){}
public void mousePressed(MouseEvent m){
switch (m.getButton()){
case MouseEvent.BUTTON1:
rotation--;
if (rotation<0) rotation=359;
repaint();
break;
case MouseEvent.BUTTON3:
rotation++;
if (rotation>360) rotation=0;
repaint();
break;
}
}
public void keyReleased(KeyEvent k){}
public void keyTyped(KeyEvent k){}
public void keyPressed(KeyEvent k){
switch (k.getKeyCode()){
case KeyEvent.VK_LEFT:
rotation--;
if (rotation<0) rotation=359;
repaint();
break;
case KeyEvent.VK_RIGHT:
rotation++;
if (rotation>360) rotation=0;
repaint();
break;
}
}
}