secondcatalogpane.java

这是一个超市管理系统

package file2;
import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class SecondCatalogPane extends JPanel implements ActionListener{
	//声明数据库连接组件
	private DBConnection con=null;
	//声明各种标签
	private JLabel tip=null;
	private JLabel name=null;
	private JLabel belongsTo=null;
	private JTextField nameTextField=null;
	private JComboBox comboBox=null;
	private JButton insert=null;
	private JButton reset=null;
	//声明装载上面声明的各种控件的面版
	private JPanel tipPane=null;
	private JPanel namePane=null;
	private JScrollPane belongsToPane=null;//装载list
	private JPanel belongstoPane=null;//装载belongsTo标签
	private JPanel buttonsPane=null;
	//private JPanel echoPane=null;//装载所有面版
	public SecondCatalogPane(){
		try{
			tip=new JLabel("请在下面输入商品明细类信息");
			name=new JLabel("名称:");
			belongsTo=new JLabel("所属类别:");
			nameTextField=new JTextField(10);
			insert=new JButton("插入");
			reset=new JButton("重置");
			tipPane=new JPanel();
			tipPane.setLayout(new FlowLayout(FlowLayout.LEFT));
			tipPane.add(tip);
			namePane=new JPanel();
			namePane.setLayout(new FlowLayout(FlowLayout.LEFT));
			namePane.add(name);
			namePane.add(nameTextField);
			belongstoPane=new JPanel();
			belongstoPane.setLayout(new FlowLayout(FlowLayout.LEFT));
			belongstoPane.add(belongsTo);
			//声明所属类别面版
			con=new DBConnection();
			String[] dataOfList=new String[100];
			dataOfList[0]="请选择商品大类:";
			String querySql="select* from First_Catalog";
			ResultSet set=con.executeSelect(querySql);
			int count=1;
			while(set.next()){
				String name=set.getString(2);
				dataOfList[count++]=name;
			}
			comboBox=new JComboBox(dataOfList);
			comboBox.setSelectedIndex(0);
			belongstoPane.add(comboBox);
			//belongsToPane=new JScrollPane(comboBox);
			buttonsPane=new JPanel();
			buttonsPane.setLayout(new FlowLayout(FlowLayout.CENTER));
			buttonsPane.add(insert);
			buttonsPane.add(reset);
			//echoPane=new JPanel();
			this.setLayout(new GridLayout(4,1));
			this.add(tipPane);
			this.add(namePane);
			this.add(belongstoPane);
			//this.add(belongsToPane);
			this.add(buttonsPane);
			//this.setLayout(new FlowLayout());
			//this.add(echoPane);
			insert.addActionListener(this);
			reset.addActionListener(this);
		}catch(SQLException sql){
			JOptionPane.showMessageDialog(null, "发生SQL错误!", "提示", JOptionPane.ERROR_MESSAGE);
			return;
		}
		
	}
	public void actionPerformed(ActionEvent e){
		if(e.getSource()==reset){
			nameTextField.setText("");
			comboBox.setSelectedIndex(0);
			return;
		}
		if(e.getSource()==insert){
			String name=nameTextField.getText().trim();
			String belongsTo=(String)comboBox.getSelectedItem();
			if(name.equals("")||belongsTo.equals("请选择商品大类:")){
				JOptionPane.showMessageDialog(null, "请您选择商品大类,且商品名称不能为空!", "警告", JOptionPane.ERROR_MESSAGE);
				return;
			}
			String querySql="select* from Second_Catalog where Second_name='"+name+"'";
			ResultSet rs=con.executeSelect(querySql);
			try{
				if(rs.next()){
					JOptionPane.showMessageDialog(null, "该名称已经存在!", "提示", JOptionPane.ERROR_MESSAGE);
					return;
				}
				String queryID="select* from First_Catalog where First_name='"+belongsTo+"'";
				ResultSet set=con.executeSelect(queryID);
				if(set.next()){
					int ID=set.getInt(1);
					String insertSql="insert into Second_Catalog values("+ID+",'"+name+"')";
					con.executeDML(insertSql);
					JOptionPane.showMessageDialog(null, "插入成功!", "提示", JOptionPane.INFORMATION_MESSAGE);
					return;
				}
				
			}catch(SQLException sql){
				JOptionPane.showMessageDialog(null, "发生SQL错误!", "提示", JOptionPane.ERROR_MESSAGE);
				sql.printStackTrace();
				return;
			}
		}
	}
}