database.java

这是我做的一个收发邮件的软件

package source;
import java.sql.*;

import javax.swing.*;

import org.eclipse.jface.dialogs.MessageDialog;
public class DataBase 
{
	Connection conn = null;
	Statement stmt = null;
	ResultSet rs = null;
	public DataBase() 
	{
		try {
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		} catch (ClassNotFoundException e) {
			 MessageDialog.openInformation(null, "系统提示！", "驱动加载错误！");
		}
	}
	public void connectToDB() {
		try 
		{	
			String url="jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=database/mail.mdb;";
			conn = DriverManager.getConnection(url,"admin","4021");
			stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
		} catch (SQLException e) {
			MessageDialog.openInformation(null, "系统提示！", "建立数据库连接错误！");
			e.printStackTrace();
		}
	}
	public ResultSet executeQuery(String sql) {
		try {
			rs = stmt.executeQuery(sql);
		} catch (SQLException e) {
			MessageDialog.openInformation(null, "系统提示！", "执行sql语句错误！");
			e.printStackTrace();
		}
		return rs;
	}
	public void executeInsert(String sql) {
		try {
			stmt.executeUpdate(sql);
		} catch (SQLException e) {
			// TODO 自动生成 catch 块
			MessageDialog.openInformation(null, "系统提示！", "执行sql语句错误！");
			e.printStackTrace();
		}
	}
	public void executeDelete(String sql) {
		try {
			stmt.executeUpdate(sql);
		} catch (SQLException e) {
			// TODO 自动生成 catch 块
			MessageDialog.openInformation(null, "系统提示！", "执行sql语句错误！");
			e.printStackTrace();
		}
	}
	public void executeUpdate(String sql) {
		try {
			stmt.executeUpdate(sql);
		} catch (SQLException e) {
			// TODO 自动生成 catch 块
			MessageDialog.openInformation(null, "系统提示！", "执行sql语句错误！");
			e.printStackTrace();
		}
	}
	public void close() {
		try {
		if(rs != null)			
			rs.close();			
		if(stmt != null)
			stmt.close();
		if(conn != null)
			conn.close();
		}catch (SQLException e) {
			// TODO 自动生成 catch 块
			MessageDialog.openInformation(null, "系统提示！", "数据库关闭错误！");
			e.printStackTrace();
		}
	}


}