我正在制作一个Java程序，可以在其中使用Java并使用SQL命令访问数据库来制作本地食谱。我试图通过在文本字段中输入名称来删除数据库条目，然后在数据库中删除具有相同名称的匹配条目。我遇到一个奇怪的错误，它说“ executeQuerey（）”不能用作更新，但是我那里仍然有更新方法。如果有人能找到解决该问题所需的措施，我将非常感激。谢谢！
/** Creates new form deleteRecipe */
public deleteRecipe() {
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() {
txtName = new javax.swing.JTextField();
jLabel1 = new javax.swing.JLabel();
btnDelete = new javax.swing.JButton();
btnBack = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
txtName.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
txtName.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
txtNameActionPerformed(evt);
}
});
jLabel1.setFont(new java.awt.Font("Lucida Grande", 1, 18)); // NOI18N
jLabel1.setText("What Recipe do you want to delete?");
btnDelete.setText("Delete!");
btnDelete.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
btnDeleteActionPerformed(evt);
}
});
btnBack.setText("Back");
btnBack.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
btnBackActionPerformed(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()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(87, 87, 87)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(txtName)))
.addGroup(layout.createSequentialGroup()
.addGap(199, 199, 199)
.addComponent(btnDelete, javax.swing.GroupLayout.PREFERRED_SIZE, 101, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(btnBack)))
.addContainerGap(80, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(btnBack)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 69, Short.MAX_VALUE)
.addComponent(jLabel1)
.addGap(30, 30, 30)
.addComponent(txtName, javax.swing.GroupLayout.PREFERRED_SIZE, 47, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(38, 38, 38)
.addComponent(btnDelete, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(34, 34, 34))
);
pack();
}// </editor-fold>
private void txtNameActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void btnBackActionPerformed(java.awt.event.ActionEvent evt) {
this.dispose();
CookbookApp ca = new CookbookApp();
ca.setVisible(true);
}
private void btnDeleteActionPerformed(java.awt.event.ActionEvent evt) {
ArrayList<Cookbook > recipes = new ArrayList();
String name = txtName.getText();
try {
String url = "jdbc:derby://localhost:1527/Cookbook";
Connection conn = DriverManager.getConnection(url);
String query = "INSERT into RECIPES(NAME, SUBCATAGORY, CATAGORY, INGREDIENTS, INSTRUCTIONS, MODIFICATIONS) values(?,?,?,?,?,?)";
PreparedStatement pst = conn.prepareStatement(query);
pst.setString(1, name);
ResultSet rs = pst.executeQuery();
Cookbook recipe;
while (rs.next()) {
recipe = new Cookbook(rs.getString("NAME"), rs.getString("SUBCATAGORY"),rs.getString("CATAGORY"), rs.getString("INGREDIENTS"), rs.getString("INSTRUCTIONS"),rs.getString("MODIFICATIONS"));
if (rs.getString(1).equalsIgnoreCase(name))
recipes.remove(recipe);
}
pst.executeUpdate();
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
// }
// public ArrayList<Cookbook> recipes() {
// ArrayList<Cookbook > recipes = new ArrayList();
//
// try {
// String url = "jdbc:derby://localhost:1527/Cookbook";
// Connection conn = DriverManager.getConnection(url);
// String query = "SELECT * FROM RECIPES";
// PreparedStatement pst = conn.prepareStatement(query);
// ResultSet rs = pst.executeQuery();
//
// Cookbook recipe;
//
// pst.setString(1, name);
//
//
// while (rs.next()) {
// recipe = new Cookbook(rs.getString("NAME"), rs.getString("SUBCATAGORY"),rs.getString("CATAGORY"), rs.getString("INGREDIENTS"), rs.getString("INSTRUCTIONS"),rs.getString("MODIFICATIONS"));
// if (rs.getString(1).equalsIgnoreCase(name))
// recipes.remove(recipe);
// }
// } catch (Exception e) {
// JOptionPane.showMessageDialog(null, e);
// }
// return recipes;
//
}
/**
* @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(deleteRecipe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(deleteRecipe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(deleteRecipe.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(deleteRecipe.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 deleteRecipe().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton btnBack;
private javax.swing.JButton btnDelete;
private javax.swing.JLabel jLabel1;
private javax.swing.JTextField txtName;
// End of variables declaration
}
这里的问题是，您尝试使用executeQuery方法执行INSERT SQL语句。当您要更新数据库（创建，更新，删除）时，必须调用executeUpdate。
如果要从数据库读取，则可以使用executeQuery方法执行此操作。