form ventana para cambiar titulos y modificar emnsajes

import javax.swing.JOptionPane;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author SEDUCA
 */
public class Ventana extends javax.swing.JFrame {

    /**
     * Creates new form Ventana
     */
    public Ventana() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                         
    private void initComponents() {

        buttonGroup1 = new javax.swing.ButtonGroup();
        txtntitulo = new javax.swing.JButton();
        txtNuevott = new javax.swing.JTextField();
        txtTA = new javax.swing.JTextField();
        txtMSN = new javax.swing.JTextField();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();
        jRBinfo = new javax.swing.JRadioButton();
        jRBaviso = new javax.swing.JRadioButton();
        jRBerror = new javax.swing.JRadioButton();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setLocation(new java.awt.Point(400, 200));

        txtntitulo.setLabel("Nuevo Titulo");
        txtntitulo.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                txtntituloActionPerformed(evt);
            }
        });

        jButton2.setText("Nueva Alerta");
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton2ActionPerformed(evt);
            }
        });

        jButton3.setText("Borrar");

        jButton4.setText("Salir");
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });

        buttonGroup1.add(jRBinfo);
        jRBinfo.setText("Info");

        buttonGroup1.add(jRBaviso);
        jRBaviso.setText("Aviso");

        buttonGroup1.add(jRBerror);
        jRBerror.setText("Error");

        jLabel1.setText("Titulo de la Alerta");

        jLabel2.setText("Mensaje de Alerta");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(104, 104, 104)
                .addComponent(jButton3)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton4)
                .addGap(162, 162, 162))
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(60, 60, 60)
                        .addComponent(jButton2, javax.swing.GroupLayout.PREFERRED_SIZE, 117, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(71, 71, 71)
                        .addComponent(jRBinfo)
                        .addGap(18, 18, 18)
                        .addComponent(jRBaviso)
                        .addGap(18, 18, 18)
                        .addComponent(jRBerror))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(40, 40, 40)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addGroup(layout.createSequentialGroup()
                                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                                    .addGroup(layout.createSequentialGroup()
                                        .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 102, javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addGap(56, 56, 56))
                                    .addGroup(layout.createSequentialGroup()
                                        .addComponent(txtntitulo, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                        .addGap(21, 21, 21)))
                                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                                    .addGroup(layout.createSequentialGroup()
                                        .addGap(54, 54, 54)
                                        .addComponent(txtNuevott))
                                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 53, Short.MAX_VALUE)
                                        .addComponent(txtTA, javax.swing.GroupLayout.PREFERRED_SIZE, 264, javax.swing.GroupLayout.PREFERRED_SIZE))))
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 153, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                .addComponent(txtMSN, javax.swing.GroupLayout.PREFERRED_SIZE, 264, javax.swing.GroupLayout.PREFERRED_SIZE)))))
                .addGap(88, 88, 88))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(97, 97, 97)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(12, 12, 12)
                        .addComponent(txtNuevott, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(18, 18, 18)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                            .addComponent(jLabel1)
                            .addComponent(txtTA, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
                    .addComponent(txtntitulo))
                .addGap(18, 18, 18)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(txtMSN, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(jLabel2))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 96, Short.MAX_VALUE)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(jButton2)
                        .addGap(100, 100, 100))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                            .addComponent(jRBaviso)
                            .addComponent(jRBerror)
                            .addComponent(jRBinfo))
                        .addGap(78, 78, 78)))
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jButton3)
                    .addComponent(jButton4))
                .addGap(46, 46, 46))
        );

        pack();
    }// </editor-fold>                       

    private void txtntituloActionPerformed(java.awt.event.ActionEvent evt) {                                          
        // TODO add your handling code here:
        String titulo=txtNuevott.getText();
        this.setTitle(""+titulo);
       
    }                                         

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                        
        // TODO add your handling code here:
        String titulo1=txtTA.getText();
        String Mensajet=txtMSN.getText();
       
        if (jRBinfo.isSelected()){
               
                JOptionPane.showMessageDialog(null,Mensajet, titulo1 ,JOptionPane.INFORMATION_MESSAGE);
       
        }
       
        if (jRBaviso.isSelected()){
       
                JOptionPane.showMessageDialog(null,Mensajet, titulo1 ,JOptionPane.WARNING_MESSAGE);
       
        }
        
        if (jRBerror.isSelected()){
       
                JOptionPane.showMessageDialog(null,Mensajet, titulo1 ,JOptionPane.ERROR_MESSAGE);
       
        }
        
    }                                       

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                        
        // TODO add your handling code here:
        System.exit(0);
    }                                       

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(Ventana.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Ventana.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Ventana.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Ventana.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Ventana().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                    
    private javax.swing.ButtonGroup buttonGroup1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JRadioButton jRBaviso;
    private javax.swing.JRadioButton jRBerror;
    private javax.swing.JRadioButton jRBinfo;
    private javax.swing.JTextField txtMSN;
    private javax.swing.JTextField txtNuevott;
    private javax.swing.JTextField txtTA;
    private javax.swing.JButton txtntitulo;
    // End of variables declaration                  
}

formularios

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author SEDUCA
 */
public class Calculo extends javax.swing.JFrame {

    /**
     * Creates new form Calculo
     */
    public Calculo() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                         
    private void initComponents() {

        txtPasajero = new javax.swing.JTextField();
        txtPrecio = new javax.swing.JTextField();
        txtGasto15 = new javax.swing.JTextField();
        txtGanancia = new javax.swing.JTextField();
        txtGasto20 = new javax.swing.JTextField();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        jLabel3 = new javax.swing.JLabel();
        jLabel4 = new javax.swing.JLabel();
        jLabel6 = new javax.swing.JLabel();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Calculo de Gasto y GananciasExcursión");

        txtPasajero.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        txtPasajero.setPreferredSize(new java.awt.Dimension(80, 28));
        txtPasajero.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                txtPasajeroActionPerformed(evt);
            }
        });

        txtPrecio.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N

        txtGasto15.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        txtGasto15.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                txtGasto15ActionPerformed(evt);
            }
        });

        txtGanancia.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        txtGanancia.setText(" ");

        txtGasto20.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        txtGasto20.setText(" ");

        jLabel1.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel1.setText("Cantidad de Pasajeros");

        jLabel2.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel2.setText("Precio del Pasaje");

        jLabel3.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel3.setText("Gastos del Seguro 15%");

        jLabel4.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel4.setText("Gasto de Excursion 20%");

        jLabel6.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N
        jLabel6.setText("Ganancia Final expresada en peso");

        jButton1.setText("jButton1");

        jButton2.setText("jButton2");

        jButton3.setText("CALCULAR");
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });

        jButton4.setText("SALIR");
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(126, 126, 126)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(txtGasto15, javax.swing.GroupLayout.PREFERRED_SIZE, 166, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 196, javax.swing.GroupLayout.PREFERRED_SIZE))
                        .addGap(139, 139, 139)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(txtGasto20, javax.swing.GroupLayout.PREFERRED_SIZE, 151, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addComponent(jLabel4, javax.swing.GroupLayout.PREFERRED_SIZE, 206, javax.swing.GroupLayout.PREFERRED_SIZE)))
                    .addComponent(txtGanancia, javax.swing.GroupLayout.PREFERRED_SIZE, 166, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(jLabel6)
                    .addComponent(jLabel2)
                    .addComponent(jLabel1)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                        .addComponent(txtPrecio, javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(txtPasajero, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, 236, Short.MAX_VALUE)))
                .addContainerGap(121, Short.MAX_VALUE))
            .addGroup(layout.createSequentialGroup()
                .addGap(63, 63, 63)
                .addComponent(jButton1)
                .addGap(101, 101, 101)
                .addComponent(jButton2)
                .addGap(117, 117, 117)
                .addComponent(jButton3)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton4)
                .addGap(91, 91, 91))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(51, 51, 51)
                .addComponent(jLabel1)
                .addGap(18, 18, 18)
                .addComponent(txtPasajero, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(16, 16, 16)
                .addComponent(jLabel2)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(txtPrecio, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(79, 79, 79)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel3)
                    .addComponent(jLabel4))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(txtGasto15, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(txtGasto20, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(18, 18, 18)
                .addComponent(jLabel6)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(txtGanancia, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 80, Short.MAX_VALUE)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jButton1)
                    .addComponent(jButton2)
                    .addComponent(jButton3)
                    .addComponent(jButton4))
                .addGap(50, 50, 50))
        );

        pack();
    }// </editor-fold>                       

    private void txtPasajeroActionPerformed(java.awt.event.ActionEvent evt) {                                           
        // TODO add your handling code here:
    }                                          

    private void txtGasto15ActionPerformed(java.awt.event.ActionEvent evt) {                                          
        // TODO add your handling code here:
    }                                         

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                        
        // TODO add your handling code here:
        System.exit(0);
    }                                       

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                        
        // TODO add your handling code here:
        //boton calculo
        int pasajero=Integer.parseInt(txtPasajero.getText());
        int preciop=Integer.parseInt(txtPrecio.getText());
        int monto=0;
        int monto2=0;
        int gasto20=0;
        monto=(pasajero*preciop);
       
        monto2=(monto*15/100);
       
        txtGasto15.setText(String.valueOf(monto2) ); //conversion string int
        gasto20=(monto*20/100);
        txtGasto20.setText(String.valueOf(gasto20));
       
    }                                       

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(Calculo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Calculo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Calculo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Calculo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Calculo().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                    
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel6;
    private javax.swing.JTextField txtGanancia;
    private javax.swing.JTextField txtGasto15;
    private javax.swing.JTextField txtGasto20;
    private javax.swing.JTextField txtPasajero;
    private javax.swing.JTextField txtPrecio;
    // End of variables declaration                  
}

ejercicio de cuadros de mensajes

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_ejercicio_01;

import javax.swing.JOptionPane;

/**
 *
 * @author SEDUCA
 */
public class POO_ejercicio_01 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
         String mensaje="Ingrese su nombre:";
         String nombre="";
         int nota1=0;
         int nota2=0;
         int nota3=0;
         int promedio=0;
        
        nombre=JOptionPane.showInputDialog(null,mensaje);
       
        //JOptionPane.showMessageDialog(null, nombre,"su nombre es:",1);
       
        mensaje="Ingrese la nota numero 1:";
        nota1=Integer.parseInt(JOptionPane.showInputDialog(null,mensaje));
        mensaje="Ingrese la nota numero 2:";
        nota2=Integer.parseInt(JOptionPane.showInputDialog(null,mensaje));
        mensaje="Ingrese la nota numero 3:";
        nota3=Integer.parseInt(JOptionPane.showInputDialog(null,mensaje));
        promedio=(nota1+nota2+nota3)/3;
       
       
       
        JOptionPane.showMessageDialog(null,"El Alumno: " + nombre + " tiene un promedio de:" + promedio);
        /*
        int seleccion=0;
        do{
            seleccion=JOptionPane.showOptionDialog(null,"¿Desea continuar?", "seleccion",
            JOptionPane.YES_NO_OPTION,JOptionPane.QUESTION_MESSAGE,null,new Object[]{"si","no"},null);
       
       
        }while(seleccion==0);
        */
    }
   
}

Mensaje o caja de mensajes en java. utilizando el JOption

import javax.swing.JOptionPane;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author SEDUCA
 */
public class main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        String mensaje="Ingrese su nombre:";
        String nombre="";
       
        int numero=0;
        nombre=JOptionPane.showInputDialog(null,mensaje);
       
        JOptionPane.showMessageDialog(null, nombre,"su nombre es:",1);
       
        mensaje="Ingrese un numeero entero:";
       
        numero=Integer.parseInt(JOptionPane.showInputDialog(null,mensaje));
       
        numero++;
       
        JOptionPane.showMessageDialog(null,"El numero incrementado en 1 es: "+numero);
       
        int seleccion=0;
        do{
            seleccion=JOptionPane.showOptionDialog(null,"¿Desea continuar?", "seleccion",
            JOptionPane.YES_NO_OPTION,JOptionPane.QUESTION_MESSAGE,null,new Object[]{"si","no"},null);
       
       
        }while(seleccion==0);
       
       
    }
   
}

crear vector de nombre y ordenar con la propiedad sort pero en lugar de numeros primitivos lo haremos los string. se mostrar ordenado y de atras hacia adelante.

ejercicio 31

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package ejercicio_mj_vector.ordenar;
//import java.util.Scanner;

import java.util.Arrays;
import java.util.Collections;


/**
 *
 * @author PC 09
 */
public class Ejercicio_mj_vectorOrdenar {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        final int LARGO=10;
        int contadorIntercambios=0;
        int aux=0;
        int[]vecNumeros=new int[LARGO];
        for (int i = 0; i < vecNumeros.length; i++) {
            vecNumeros[i]=(int)(Math.random()*100);
        }
 
     String[] vecNombres={"Daniel","Fer","Arturo","Genaro"};
        for (int i = 0; i < vecNombres.length; i++) {
            System.out.print(vecNombres[i]+" ");
        }
        System.out.println("");
        Arrays.sort(vecNombres);
        for (int i = 0; i < vecNombres.length; i++) {
            System.out.print(vecNombres[i]+" ");
        }
        Arrays.sort(vecNombres,Collections.reverseOrder());
        System.out.println("");
     
        for (int i = 0; i < vecNombres.length; i++) {
            System.out.print(vecNombres[i]+" ");
        }
        System.out.println("");
     
         
         
     
        }
    }

ejercicio 13 martes

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package ejercicio_mj_prueba01;
import java.util.Scanner;
/**
 *
 * @author CFP31-26
 */
public class Ejercicio_mj_prueba01 {
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
         int sexo,acumulado=0,i,importe, servicio;
         int corteMujer=300,corteHombre=200,peinado=600,brishing=250,color=500,afeitar=100;
               
        //sexo: el genero del cliente//acumulado el total de la suma de los clientes//importe:el pago de cada cliente//i=contador
        Scanner entrada = new Scanner (System.in);
     
        System.out.println("Incluya el genero del Cliente 0=salir, 1=hombre, 2=mujer");
        sexo=entrada.nextInt();
     
        switch (sexo){
            case 1:
            System.out.println("Ingrese el servicio que desea 1 para corto, 2 para afeitado");
            servicio = entrada.nextInt();
            //importe=entrada.nextInt(); ***El importe no lo decide el usuario
            do{
                switch(servicio){ //Los valores se suman aquí, no están en variables
                case 1:
                    acumulado=acumulado+200;
                    break;
                case 2:
                    acumulado=acumulado+100;
                    break;
             
            }
        }

-----------------------
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package ejercicio_cortes_de_pelo;
import java.util.Scanner;
/**
 *
 * @author MedinaDiaz
 */
public class Ejercicio_cortes_de_pelo {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        //-----------------variables------------------------
        int sexo,acumulado=0,i,importe, servicio=0,servicio2=0;
         int corteMujer=300,corteHombre=200,peinado=600,brishing=250,color=500,afeitar=100;
             
        //sexo: el genero del cliente//acumulado el total de la suma de los clientes//importe:el pago de cada cliente//i=contador
        //----------------------------------------
        Scanner entrada = new Scanner (System.in);
       //do
        System.out.println("Incluya el genero del Cliente 0=salir, 1=hombre, 2=mujer");
        sexo=entrada.nextInt();
        System.out.println("Ingrese el servicio que desea.");
        switch (sexo){
            case 1:
                System.out.println("servicio para hombre");
                System.out.println("corte");
                System.out.println("afeitar");
                servicio = entrada.nextInt();
                switch(servicio){
                    case 1:;
                        acumulado=acumulado+corteHombre;
                        break;
                    case 2:;
                        acumulado=acumulado+afeitar;
                        break;
                }
            case 2:
             
                    //case 1:
                    System.out.println("servicio para mujer");
                    System.out.println("corte");
                    System.out.println("peinado");
                    System.out.println("brishing");
                    System.out.println("color");
                    servicio2 = entrada.nextInt();
                    switch(servicio2){
                        case 1:;
                            acumulado=acumulado+corteMujer;
                            break;
                        case 2:;
                            acumulado=acumulado+peinado;
                            break;
                        case 3:;
                            acumulado=acumulado+brishing;
                            break;
                        case 4:;
                            acumulado=acumulado+color;
                            break;
                        default:;
                            break;

                    }
                }
         
            }
        }

clases java 3

 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package mj_ejercicio_13;
import java.util.Scanner;
//ejercicio para calcular el costo de una excursion.


/**
 *
 * @author CFP31-26
 */
public class Mj_ejercicio_13 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        //declarar
        int c_personas,p_excursion;
        c_personas=20;
        p_excursion=500;
        double total_neto,m_bruto_d,d_diezp,d_quince,comision_seguro,comision_personas;
       
        Scanner teclado = new Scanner(System.in);
        //personas y precio c/u
        m_bruto_d=(c_personas*p_excursion);
     
        //comision del 15 para la compañia de seguro
        comision_seguro=(m_bruto_d*0.15);
     
        //monto neto (bruto) para aplicar los otros descuengo.
        total_neto=(comision_seguro-m_bruto_d);
        if (c_personas >= 20){
            d_diezp=(total_neto*0.1);
            }else{
            if (c_personas >= 30);
               d_diezp=(total_neto*0.15);
                   
        }
     
     
     
     
     
     
     
       
    }
 
}

---------------------------------------
ejercicio 12
cargar las tres notas parciales de un alumno y calcular su promedio, luego informar su situacion,
 aprobado, reprobado, aplazado, o error en el ingreso de notas teniendo en cuenta que.
.aprobado si el promedio >=7 y menor igual a 10.
.reprobado si el promedio >=4 y menor a 7
. aplazado si el promedio >=1 y menor a 4
. mostrar error si no esta entre 1 al 10

solucion. java

package mj_ejercicio_12;
import java.util.Scanner;
     
/**
 *
 * @author CFP31-26
 */
public class Mj_ejercicio_12 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        // resolucion de ejercicio 12
        int nota1,nota2,nota3;
        double promedio;
        promedio=0;
        System.out.println("ingrese nota 1:");
        Scanner teclado = new Scanner(System.in);
        nota1=teclado.nextInt();
     
        System.out.println("ingrese nota 2:");
        nota2=teclado.nextInt();
     
        System.out.println("ingrese nota 3:");
        nota3=teclado.nextInt();
        promedio=(nota1+nota2+nota3)/3;
     
        if ((nota1<1)||(nota1>10)||(nota2<1)||(nota2>10)||(nota3<1)||(nota3>10)){
                         
               // || (nota1>10)||(nota2<1) || (nota2>10){**//
            System.out.println("Error");
        }else{
             
            if (promedio >= 7 && promedio <=10){
                System.out.println ("Aprobado");
                }

                if(promedio>=4 && promedio<7){
                System.out.println("Reprobado");
                } else if (promedio>=1 && promedio<4){
                System.out.println("Aplazado");
                 System.out.println("Su Promedio es: "+promedio);
                }
        }
-----------------------------------------------
package mj_06_lecturateclado;

import java.util.Scanner;

/**
 *
 * @author CFP31-26
 */
public class MJ_06_lecturateclado {
//se debe crear una clase scanner
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        String  nombre;
        int edad;
        nombre="";
        edad=0;
        System.out.println("ingrese su nombre:");
        Scanner teclado = new Scanner(System.in);
        nombre=teclado.nextLine();
        System.out.println("INGRESE SU EDAD:");
        edad=teclado.nextInt();
        System.out.println("su nombre es: "+nombre+" y su edad es:"+edad);
     
    }
 
}

------------------------------

package mj_05_tipofloat.java;

/**

 *

 * @author CFP31-26

 */

public class Mj_05_tipofloatJava {

    /**

     * @param args the command line arguments

     */

    public static void main(String[] args) {

        // TODO code application logic here

        float numero;

        numero=7/3f;

        System.out.println(numero);

        

    }

    

}

--------------------------------------

public class Mj_03_tipostring {

    /**

     * @param args the command line arguments

     */

    public static void main(String[] args) {

        // TODO code application logic here

        String nombre;

        nombre="codo a codo";

        System.out.println(nombre);

        

    }

    

}

--------------------------------------

 package mj_03_operacionesjava;

/**

 *

 * @author CFP31-26

 */

public class Mj_04_operacionesjava {

    /**

     * @param args the command line arguments

     */

    public static void main(String[] args) {

        // TODO code application logic here

        int numero;

        numero=5+7;

        System.out.println("El Resultado de la suma es:"+numero);

    }

    

}

.---------------------------------------

package mj_02_suma;

/**

 *

 * @author CFP31-26

 */

public class MJ_02_suma {

    /**

     * @param args the command line arguments

     */

    public static void main(String[] args) {

        // TODO code application logic here

        //suma de dos numeros sin variables

        System.out.println(5+7);

        System.out.println(54);

        System.out.println("Hola");

              

    }

    

}

------------------------------------------

Ejemplos: 161, 2992, 3003, 2882,

 */

package ej3.capicua;

import java.util.Scanner;

/**

 * @author Natalia

 */

public class Ej3Capicua {

    public static void main(String[] args) {

        String frase;

        int cont=0;

        Scanner entrada = new Scanner(System.in);

        System.out.print("Ingrese una frase: ");

        frase = entrada.nextLine();

        

        //se convierte string en array de caracteres

        char[] reves = new char[frase.length()];

        char[] arreglo = frase.toCharArray();

       

        //se crea un array con la palabra ingresada ordenados los caracteres al reves

        for (int i = 0; i < arreglo.length; i++) {

            reves[arreglo.length - i - 1] = arreglo[i];

        }

        // se comparan los arreglos

        for (int i = 0; i < arreglo.length; i++) {

            if (arreglo[i] == reves[i]) {

                cont = cont + 1;

            }

        }

        if (cont == arreglo.length) {

            System.out.println("la palabra es capicua");

        } else {

            System.out.println("la palabra no es capicua");

        }

    }

}

ejercicio 13

package mj_ejercicio_13;
import java.util.Scanner;
//ejercicio para calcular el costo de una excursion.


/**
 *
 * @author CFP31-26
 */
public class Mj_ejercicio_13 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        //declarar
        int c_personas,p_excursion; // cantidad de persona,precio de la excursion
        c_personas=24;  //cantidad de personas
        p_excursion=500;
        double costos;
        costos=0;
        double neto,valorCongastseg;
        valorCongastseg=0;
        Scanner teclado = new Scanner(System.in);
 
        if (c_personas > 20 && c_personas < 30){
            costos=((c_personas*p_excursion)-((c_personas*p_excursion)*0.1));
            }
         if (c_personas >= 30){
               costos=((c_personas*p_excursion)-((c_personas*p_excursion)*0.15));
            }
           //System.out.println(""+costos);
         
           valorCongastseg=(costos*0.15);
         
            neto=(costos-valorCongastseg);
         
            System.out.println("Gasto de Excursion:"+valorCongastseg);
            System.out.println("Le toca a la compañia de seguro:"+neto);
         
     
     
     
    }
}

ejercicio java 14

 */
package mj_ejercicio_15;
import java.util.Scanner;


/**
 *
 * @author CFP31-26
 */
public class Mj_ejercicio_15 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
     int numMenor,auxMenor,numMayor;
     numMenor=0;
     numMayor=0;
     auxMenor=0;
     Scanner teclado = new Scanner (System.in);
        System.out.println("Ingrese el numero Menor:");
        numMenor=teclado.nextInt();;
        System.out.println("Ingrese el numero Mayor");
        numMayor=teclado.nextInt();
     
        if (numMenor>numMayor) {
            System.out.println("El numero menor es mayor se cambiaran los datos");
            auxMenor=numMenor;
            numMenor=numMayor;
            numMayor=auxMenor;
         
        }else{
            System.out.println("El numero menor esta ingresado correctamente");
     
        }
        System.out.println("este es el menor: "+numMenor);
    }
 
}

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

import java.util.Scanner;

/**
 *
 * @author SEDUCA
 */
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
       
        Producto mouse=new Producto("Mouse",200);
        System.out.println(mouse.calcularPrecioFinal());
        System.out.println("El Iva es:" + mouse.calcularIva());
        System.out.println("El Deuda es:" + mouse.calcularDeuda());
        mouse.informarProducto();
    }
   
}
*******************************
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

/**
 *
 * @author SEDUCA
 */
public class Producto implements Contable {
    private String producto;
    private double costo;
   
    public Producto(String producto,double costo){
    this.producto=producto;
    this.costo=costo;
    }
    //implementacion de los metodos adstractos:
    @Override
    public double calcularIva(){
    return calcularPrecioFinal()*IVA;
    }
    @Override
    public double calcularPrecioFinal(){
    return calcularPrecio()+calcularPrecio()*IVA;
    }
   
    @Override
    public double calcularDeuda(){
    return calcularPrecio()+calcularPrecio()*DEUDA;
    }
   
   
   
    //Metodo privados:
    private double calcularPrecio(){
    return (double)(this.costo+this.costo*GANANCIA);
    }

    @Override /// este proceso con la palabra void hace un proceso.
    public void informarProducto() {
        System.out.println("Este Producto es:" +this.producto);
    }
   
    
}
*****************************
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

/**
 *
 * @author SEDUCA
 */
public interface Contable {
    //CONSTANTES:
    public final double IVA=0.21;
    public final double GANANCIA=0.5;
    public final double DEUDA=0.2;
   
    //METODOS ABSTRACTOS:
    public double calcularPrecioFinal();
    public double calcularIva();
    public double calcularDeuda();
    public void informarProducto();
   
}

clase de interfas

..............................clase main................................
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

/**
 *
 * @author SEDUCA
 */
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        Producto mouse=new Producto("Mouse",100);
        System.out.println(mouse.calcularPrecioFinal());
        System.out.println("El Iva es:" + mouse.calcularIva());
    }
   
}
................................class Producto.........................................

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

/**
 *
 * @author SEDUCA
 */
public class Producto implements Contable {
    private String producto;
    private double costo;
   
    public Producto(String producto,double costo){
    this.producto=producto;
    this.costo=costo;
    }
    //implementacion de los metodos adstractos:
    @Override
    public double calcularIva(){
    return calcularPrecioFinal()*IVA;
    }
    @Override
    public double calcularPrecioFinal(){
    return calcularPrecio()+calcularPrecio()*IVA;
    }
   

    //Metodo privados:
    private double calcularPrecio(){
    return (double)(this.costo+this.costo*GANANCIA);
    }
   
}
............................interfas  contable..................................

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package poo_mj_interfas;

/**
 *
 * @author SEDUCA
 */
public interface Contable {
    //CONSTANTES:
    public final double IVA=0.21;
    public final double GANANCIA=0.5;
   
    //METODOS ABSTRACTOS:
    public double calcularPrecioFinal();
    public double calcularIva();
   
}