dbmess.java

基于JSP的家电连锁超市管理系统 数据库也在文件内

package electric.dbs;

import java.sql.*;
import javax.servlet.http.*;
import java.text.SimpleDateFormat;
import electric.*;
import electric.electricUtils.*;

public class Dbmess
{
	//将执行操作的sql语句定义为final,增加执行操作的速度
	private static final String LOAD_MESS_BY_ID="SELECT * FROM [MESS] WHERE [ID]=?";
	//执行插入的预执行语句
	private static final String INSERT_MESS="INSERT INTO [MESS]([Id],[Mname],[Mtext],[Mnote],[Createdate],[Status]) VALUES"+
	  "(?,?,?,?,?,?)";
	//执行更新操作的预执行语句
	private static final String UPDATE_MESS="UPDATE [MESS] SET [Id]=?,[Mname]=?,[Mtext]=?,[Mnote]=?,[Createdate]=?,[Status]=?"+
	  "WHERE [Id]=?";
	//执行删除的预执行语句
	private static final String DEL_MESS="UPDATE [MESS] SET [Status]=? WHERE [Id]=?";
	//设置变量名称
	private int Id;
	private String Mname;
	private String Mtext;
	private String Mnote;
	private String Createdate;
	private int Status;
	public Dbmess()
	{
	}
	
	//getXXX()
	public int getId()
	{
		return this.Id;
	}
	public String getMname()
	{
		return this.Mname;
	}
	public String getMtext()
	{
		return this.Mtext;
	}
	public String getCreatedate()
	{
		return this.Createdate;
	}
	public String getMnote()
	{
		return this.Mnote;
	}
	public int getStatus()
	{
		return this.Status;
	}
	
	//setXXX()
	public void setId(int Id)
	{
		this.Id=Id;
		saveToDb();
	}
	public void setMname(String Mname)
	{
		this.Mname=Mname;
		saveToDb();
	}
	public void setMtext(String Mtext)
	{
		this.Mtext=Mtext;
		saveToDb();
	}
	public void setMnote(String Mnote)
	{
		this.Mnote=Mnote;
		saveToDb();
	}
	public void setCreatedate(String Createdate)
	{
		this.Createdate=Createdate;
		saveToDb();
	}
	public void setStatus(int Status)
	{
		this.Status=Status;
		DELToDb();
	}
	//从前台提取信息，进行插入的操作
	public Dbmess(HttpServletRequest request)
	{
		//使用request对象获取前台信息
		//使用类DbSequenceManager,获得增长的编号
		this.Id=DbSequenceManager.nextID(FinalConstants.T_MESS);
		this.Mname=ParamUtils.getEscapeHTMLParameter(request,"mname");
		this.Mtext=ParamUtils.getEscapeHTMLParameter(request,"mtext");
		this.Mnote=ParamUtils.getEscapeHTMLParameter(request,"mnote");
		//使用类SimpleDateFormat对日期格式进行格式化
		SimpleDateFormat simpleDate=new SimpleDateFormat("yyyyMMdd");
		String shiftDateToDate=simpleDate.format(new java.util.Date());
		this.Createdate=shiftDateToDate;
		this.Status=FinalConstants.STATUS_NORMAL;
		insertIntoDb();	
	}
	
	//在构造函数中调用loadFromDb()执行读取操作
	public Dbmess(int Id) throws MessNotFoundException
	{
		this.Id=Id;
		if(Id<=0)
		{
			return;
		}
		loadFromDb();
	}
	
	//执行读取操作的方法loadFromDb()
	private void loadFromDb() throws MessNotFoundException
	{
		Connection con=null;
		PreparedStatement pstmt=null;
		try
		{
			con=DbConnectionManager.getConnection();
			pstmt=con.prepareStatement(LOAD_MESS_BY_ID);
			pstmt.setInt(1,Id);
			ResultSet rs=pstmt.executeQuery();
			if(!rs.next())
			{
				throw new MessNotFoundException("从数据表[MESS]中读取用户数据失败，欲读取的用户ID:["+Id+"]!");
			}
			this.Id=rs.getInt("ID");
			this.Mname=rs.getString("Mname");
			this.Mtext=rs.getString("Mtext");
			this.Mnote=rs.getString("Mnote");
			this.Createdate=rs.getString("Createdate");
			this.Status=rs.getInt("Status");
		}
		catch(SQLException sqle)
		{
			System.out.println("错误位置：DbMess:loadFromDb()-"+sqle);
			sqle.printStackTrace();
		}
		finally
		{
			try
			{
				pstmt.close();
				con.close();
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
	}
	
	//执行添加操作的方法
	private void insertIntoDb()
	{
		Connection con=null;
		PreparedStatement pstmt=null;
		try
		{
			con=DbConnectionManager.getConnection();
			pstmt=con.prepareStatement(INSERT_MESS);
			pstmt.setInt(1,this.Id);
			pstmt.setString(2,StringUtils.toChinese(this.Mname));
			pstmt.setString(3,StringUtils.toChinese(this.Mtext));
			pstmt.setString(4,StringUtils.toChinese(this.Mnote));
			pstmt.setString(5,StringUtils.toChinese(this.Createdate));
			pstmt.setInt(6,this.Status);
			pstmt.executeUpdate();
		}
		catch(SQLException sqle)
		{
			System.out.println("错误位置：DbMess:insertIntoDb()-"+sqle);
			sqle.printStackTrace();
		}
		finally
		{
			try
			{
				pstmt.close();
				con.close();
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
	}
	
	//使用方法saveToDb进行更新操作
	private void saveToDb()
	{
		Connection con=null;
		PreparedStatement pstmt=null;
		try
		{
			con=DbConnectionManager.getConnection();
			pstmt=con.prepareStatement(UPDATE_MESS);
			pstmt.setString(1,StringUtils.toChinese(this.Mname));
			pstmt.setString(2,StringUtils.toChinese(this.Mtext));
			pstmt.setString(3,StringUtils.toChinese(this.Mnote));
			pstmt.setString(4,StringUtils.toChinese(this.Createdate));
			pstmt.setInt(5,this.Status);
			pstmt.setInt(6,this.Id);
			pstmt.executeUpdate();
		}
		catch(SQLException sqle)
		{
			System.out.println("错误位置：DbMess:saveToDb()-"+sqle);
			sqle.printStackTrace();
		}
		finally
		{
			try
			{
			    pstmt.close();
			    con.close();	
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
	}
	
	//使用DELToDb()进行删除操作
	private void DELToDb()
	{
		Connection con=null;
		PreparedStatement pstmt=null;
		try
		{
			con=DbConnectionManager.getConnection();
			pstmt=con.prepareStatement(DEL_MESS);
			pstmt.setInt(1,this.Status);
			pstmt.setInt(2,this.Id);			
			pstmt.executeUpdate();
		}
		catch(SQLException sqle)
		{
			System.out.println("错误位置：DbMess:insertIntoDb()-"+sqle);
			sqle.printStackTrace();
		}
		finally
		{
			try
			{
				pstmt.close();
				con.close();
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
		}
	}
}