database.java

我们做的J2EE课程设计实验,使用JSF语言编写一个简易的订单系统,麻雀虽小五脏俱全,适合初学者学习J2EE时参考,代码简炼精深,具有一定的参考价值.

package ch6;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;

public class database {
	public Connection con;
	private String Order;
	private String Buyer;
	//private String  Sum;
	private String Itemnum;
	private String Item;
	private String  Num;
	private String  Price;
	//初始化连接。
	public database()
	{
	String CLASSFORNAME="com.microsoft.jdbc.sqlserver.SQLServerDriver";
	String SERVANDDB="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=scm";
	String USER="sa";
	String PWD="bigtwo863158"; 
	Order="";
	Buyer="";
	//Sum=0;
	Itemnum="";
	Item="";
	Price="";
	Price="";
	try
	{
	Class.forName(CLASSFORNAME);
	con = DriverManager.getConnection(SERVANDDB,USER,PWD);
	}
	catch(Exception e)
	{
	//System.out.println("slkdjf");
	e.printStackTrace();
	}
	}
	public void setOrder(String OrderStr){Order=OrderStr.trim();}
	public void setBuyer(String BuyerStr){Buyer=BuyerStr.trim();}
	//public void setSum(String Sumin){Sum=Sumin.trim();}
	public void setItemnum(String ItemnumStr){Itemnum=ItemnumStr.trim();}
	public void setItem(String ItemStr){Item=ItemStr.trim();}
	public void setNum(String Numin){Num=Numin.trim();}
	public void setPrice(String Pricein){Price=Pricein.trim();} 
	public String getOrder(){return Order;}
	public String getBuyer(){return Buyer;}
	//public String  getSum(){return Sum;}
	public String getItemnum(){return Itemnum;}
	public String getItem(){return Item;}
	public String  getNum(){return Num;}
	public String  getPrice(){return Price;}
	public ResultSet getorder()
	{
	try
	{
	Statement stm=con.createStatement();
	ResultSet result=stm.executeQuery("select * from t_order");
	//System.out.println("slkdjf");
	return result;
	}
	catch(Exception e)
	{
		return null;
	}
	}
	public ResultSet getorderitem()
	{
		try
		{
		Statement stm=con.createStatement();
		ResultSet result=stm.executeQuery("select * from t_orderItem");
		//System.out.println("slkdjf");
		return result;
		}
		catch(Exception e)
		{
			System.out.print(e);
			return null;
		}
	}
	public ResultSet search_order()
	{
	    //System.out.print(1234);
		int len=10-Order.length();
		for(int i=0;i<len;i++)
			Order=Order+" ";
		String sentence="select * from t_order where [Order]='"+Order+"'";
	  
		try{
		  Statement stm=con.createStatement();
		  ResultSet result=stm.executeQuery(sentence);
		  return result;
	  }
		catch(Exception e)
		{
			System.out.print(123);
			return null;
		}
	}
	public ResultSet search_orderitem()
	{
		int len=10-Order.length();
		for(int i=0;i<len;i++)
			Order=Order+" ";
		String sentence="select * from t_orderitem where [Order]='"+Order+"'";
		try{
			Statement stm=con.createStatement();
			ResultSet result=stm.executeQuery(sentence);
			return result;
		}
		catch(Exception e)
		{
			return null;
		}
	}
	public boolean addContent()
	{
		ResultSet result=search_order();
		//System.out.print(Buyer);
		//System.out.print(Item);
		//System.out.print(Itemnum);
		//System.out.print(Price);
		//System.out.print(Num);
		int Sum=Integer.parseInt(Price)*Integer.parseInt(Num);
		int su=0;
		String name;
		try
		{
			while(result.next())
			su=result.getInt(3);
			result.close();
			Statement stm=con.createStatement();
			stm.execute("delete from t_order where [Order]='"+Order+"'");
			Sum=su+Sum;
			stm.close();
		PreparedStatement pstmt=con.prepareStatement("insert into t_order values(?,?,?)");
		pstmt.setString(1, Order);
		pstmt.setString(2, Buyer);
		pstmt.setInt(3, Sum);
		pstmt.executeUpdate();
		PreparedStatement pst=con.prepareStatement("insert into t_orderitem values(?,?,?,?,?)");
		    pst.setString(1,Order);
		    pst.setString(2,Itemnum);
		    pst.setString(3, Item);
		    pst.setInt(4, Integer.parseInt(Num));
		    pst.setInt(5, Integer.parseInt(Price));
		    pst.executeUpdate();
		    
		}
		catch(Exception e)
		{
			System.out.print(e);
			return false;
		}
		return true;
	}
	public boolean Change()
	{
		int sum;
		String name="";
		int sumbin=0;
        int sumbin2=0;
		try
		{
		sum=Integer.parseInt(Num)*Integer.parseInt(Price);
		Statement stm=con.createStatement();
		ResultSet result=stm.executeQuery("select * from t_orderItem where [Order]='"+Order+"' and [Itemnum]='"+Itemnum+"'");
		while(result.next())
		{
		sumbin=result.getInt("Price")*result.getInt("Num");
		name=result.getString("Item");
		//stm.close();
		result.close();
		//Statement stm=con.createStatement();
		stm.executeUpdate("delete from t_orderItem where [Order]='"+Order+"' and [Itemnum]='"+Itemnum+"'");
		PreparedStatement stm1=con.prepareStatement("insert into t_orderItem values(?,?,?,?,?)");
		stm1.setString(1, Order);
		stm1.setString(2, Itemnum);
		stm1.setString(3, name);
		stm1.setInt(4,Integer.parseInt(Price));
		stm1.setInt(5,Integer.parseInt(Num));
		stm1.executeUpdate();
		stm1.close();
		result=stm.executeQuery("select * from t_order where [Order]='"+Order+"'");
		while(result.next())
		{
		 name=result.getString("Buyer");
		 sumbin2=result.getInt("Sum");
		}
		sum=sumbin2-sumbin+sum;
		stm.executeUpdate("delete from t_order where [Order]='"+Order+"'");
		stm1=con.prepareStatement("insert into t_order values(?,?,?)");
		stm1.setString(1,Order);
		stm1.setString(2,name);
		stm1.setInt(3,sum);
		stm1.executeUpdate();
		return true;
		}
		return false;
	   }
		catch(Exception e)
		{
			e.printStackTrace();
			return false;
		}
	}
	public boolean del()
	{
		int sum;
		try{
			Statement stm=con.createStatement();
			ResultSet result=stm.executeQuery("select * from t_orderItem where [Order]='"+Order+"' and [Itemnum]='"+Itemnum+"'");
			while(result.next())
			{
				sum=result.getInt("Price")*result.getInt("Num");
				stm.execute("delete from t_orderItem where [Order]='"+Order+"' and [Itemnum]='"+Itemnum+"'");
				result=stm.executeQuery("select * from t_order where Ordernum='"+Order+"'");
				while(result.next())
				{
				String name=result.getString("Buyer");
				int sumbin=result.getInt("Sum");
				stm.execute("delete from t_order where [Order]='"+Order+"'");
				stm.close();
				PreparedStatement state=con.prepareStatement("insert into t_order values(?,?,?)");
				state.setString(1, Order);
				state.setString(2, name);
				state.setInt(3, sumbin-sum);
				state.executeUpdate();
				return true;
				}
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
			return false;
		}
		return false;
	}	
}