我正在尝试使用嵌入式数据库构建Java应用程序。它与CRUD应用程序非常类似，我深入研究了许多为oracle和netbeans提供的教程，如下所示：
http://platform.netbeans.org/tutorials/nbm-crud.html
http://netbeans.org/kb/70/java/gui-db.html
但是，这个构建会自动建立一个基于crud动作的默认界面，而这不是我想要的。我假装自己定制所有界面，并在需要时访问derby嵌入式数据库来执行某些操作。
同时我只有两个.java文件。 JFrame包含由设计菜单上添加的元素生成的代码：
package interface_aquitex;
import aquitex.Aquitex;
import javax.swing.JOptionPane;
public class design_aquitex extends javax.swing.JFrame {
/**
* Creates new form design_aquitex
*/
public design_aquitex() {
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() {
jFrame1 = new javax.swing.JFrame();
jLabel1 = new javax.swing.JLabel();
jLabel2 = new javax.swing.JLabel();
jTextField1 = new javax.swing.JTextField();
jTextField2 = new javax.swing.JTextField();
jButton1 = new javax.swing.JButton();
jLabel3 = new javax.swing.JLabel();
jButton2 = new javax.swing.JButton();
jMenuBar1 = new javax.swing.JMenuBar();
jMenu1 = new javax.swing.JMenu();
jMenuItem1 = new javax.swing.JMenuItem();
jMenu2 = new javax.swing.JMenu();
jFrame1.setMinimumSize(new java.awt.Dimension(400, 400));
jLabel1.setText("Nome:");
jLabel2.setText("Idade:");
jTextField1.setName(""); // NOI18N
jTextField1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jTextField1ActionPerformed(evt);
}
});
jTextField1.addPropertyChangeListener(new java.beans.PropertyChangeListener() {
public void propertyChange(java.beans.PropertyChangeEvent evt) {
jTextField1PropertyChange(evt);
}
});
jTextField1.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
jTextField1KeyPressed(evt);
}
});
jButton1.setText("Inserir");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jLabel3.setText("Dados");
jButton2.setText("Listar");
javax.swing.GroupLayout jFrame1Layout = new javax.swing.GroupLayout(jFrame1.getContentPane());
jFrame1.getContentPane().setLayout(jFrame1Layout);
jFrame1Layout.setHorizontalGroup(
jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jFrame1Layout.createSequentialGroup()
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jFrame1Layout.createSequentialGroup()
.addGap(26, 26, 26)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel1)
.addComponent(jLabel2))
.addGap(37, 37, 37)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(jTextField1, javax.swing.GroupLayout.DEFAULT_SIZE, 56, Short.MAX_VALUE)
.addComponent(jTextField2)))
.addGroup(jFrame1Layout.createSequentialGroup()
.addGap(57, 57, 57)
.addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 64, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 92, Short.MAX_VALUE)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton2)
.addComponent(jButton1))
.addGap(94, 94, 94))
);
jFrame1Layout.setVerticalGroup(
jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jFrame1Layout.createSequentialGroup()
.addGap(24, 24, 24)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel1)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(5, 5, 5)
.addComponent(jButton1)
.addGap(4, 4, 4)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(88, 88, 88)
.addGroup(jFrame1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 37, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jButton2))
.addContainerGap(79, Short.MAX_VALUE))
);
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jMenu1.setText("File");
jMenuItem1.setText("jMenuItem1");
jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jMenuItem1ActionPerformed(evt);
}
});
jMenu1.add(jMenuItem1);
jMenuBar1.add(jMenu1);
jMenu2.setText("Edit");
jMenuBar1.add(jMenu2);
setJMenuBar(jMenuBar1);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 400, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 279, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
public String getjTextField1(){
JOptionPane.showMessageDialog(null,jTextField1.getText());
return jTextField1.getText();
}
public int getjTextField2(){
int idade;
idade = Integer.parseInt(jTextField2.getText());
System.out.println(idade);
return idade;
}
private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
jFrame1.setVisible(true);
}
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
Aquitex a = new Aquitex();
a.saveRecord();
}
private void jTextField1PropertyChange(java.beans.PropertyChangeEvent evt) {
// TODO add your handling code here:
}
private void jTextField1KeyPressed(java.awt.event.KeyEvent evt) {
JOptionPane.showMessageDialog(null,jTextField1.getText());
}
/**
* @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(design_aquitex.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(design_aquitex.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(design_aquitex.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(design_aquitex.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 design_aquitex().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JFrame jFrame1;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JMenu jMenu1;
private javax.swing.JMenu jMenu2;
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JMenuItem jMenuItem1;
private javax.swing.JTextField jTextField1;
private javax.swing.JTextField jTextField2;
// End of variables declaration
}
和我创建的类：
package aquitex;
import interface_aquitex.design_aquitex;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
public class Aquitex extends JFrame{
private static PreparedStatement stmtSaveNewRecord=null;
private static Connection dbConnection = null;
String tabelaExp =
"CREATE table APP.Alunos ("+
" ID INTEGER NOT NULL"+
" PRIMARY KEY GENERATED ALWAYS AS IDENTITY "+
" (START WITH 1, INCREMENT BY 1),"+
"FIRSTNAME VARCHAR(30),"+
"AGE INT )";
private void setDBSystemDir() {
// Decide on the db system directory: <userhome>/.aquitex/
String userHomeDir = System.getProperty("user.home", ".");
String systemDir = userHomeDir + "/.aquitex";
// Set the db system directory.
System.setProperty("derby.system.home", systemDir);
}
private boolean createTables(Connection dbConnection) {
boolean bCreatedTables = false;
Statement statement = null;
try {
statement = dbConnection.createStatement();
statement.execute(tabelaExp);
bCreatedTables = true;
} catch (SQLException ex) {
ex.printStackTrace();
}
return bCreatedTables;
}
public int saveRecord() {
design_aquitex da = new design_aquitex();
try {
stmtSaveNewRecord = dbConnection.prepareStatement(
"INSERT INTO APP.Alunos " +
" (FIRSTNAME, AGE) " +
"VALUES (?, ?)",
Statement.RETURN_GENERATED_KEYS);
} catch (SQLException ex) {
Logger.getLogger(Aquitex.class.getName()).log(Level.SEVERE, null, ex);
}
int id = -1;
try {
stmtSaveNewRecord.clearParameters();
stmtSaveNewRecord.setString(1, da.getjTextField1());
stmtSaveNewRecord.setInt(2, da.getjTextField2());
int rowCount = stmtSaveNewRecord.executeUpdate();
ResultSet results = stmtSaveNewRecord.getGeneratedKeys();
if (results.next()) {
id = results.getInt(1);
}
} catch(SQLException sqle) {
sqle.printStackTrace();
}
return id;
}
public static void main(String[] args) {
// TODO code application logic here
String userHomeDir = System.getProperty("user.home", ".");
String systemDir = userHomeDir + "/.aquitex";
// Set the db system directory.
System.setProperty("derby.system.home", systemDir);
String strUrl = "jdbc:derby:aquitex_db;create=true";
Properties props = new Properties();
props.put("user", "adm_aquitex");
props.put("password", "pass_aquitex");
try {
dbConnection = DriverManager.getConnection(strUrl, props);
} catch (SQLException ex) {
Logger.getLogger(Aquitex.class.getName()).log(Level.SEVERE, null, ex);
}
//Aquitex a = new Aquitex();
//a.createTables(dbConnection);
design_aquitex da = new design_aquitex();
da.setVisible(true);
}
}
目前，我真正需要的是如何将界面与数据库分开的一些亮点，我的意思是，在它们之间使用“类”或其他东西，以便它们不会相互“接触”。
我的另一个问题是关于数据库中的表格。他们是否需要每个类的class.java文件？那么本教程中介绍的Entity Manager类如何： http://platform.netbeans.org/tutorials/nbm-crud.html
我需要使用它吗？我正在使用德比数据库。
Sory这么长时间的问题，但我现在有点迷失了如何在一个带有自定义界面的java crud桌面应用程序中构建结构，以及如何制作图层（ “swing”，“db”和分隔它们的那个“）相互连接。
答案 0 :(得分：2)
1）你的第一个文件（它的名字是什么？）应该包含所有的GUI内容。
2）你的第二个文件（“Aquitex.java”？）应不从JFrame扩展，并且不必须有任何GUI内容。
3）您的主表单将创建一个“Aquitex”实例。
4）第一个类中的UI事件处理程序将在第二个类中调用公共方法。