zhandian_procedure.java

java做的 公交车查询系统....毕业设计

//后台处理,用于zhandian.jsp的处理
package gongjiaochexitong.gongjiaoche.zhandian_pkg;

import gongjiaochexitong.gongjiaoche.*;

import java.sql.*;
import java.util.Vector;

public class zhandian_procedure {  //后台处理(站点列表 + 车次列表)
	
	//将站点名取出显示在列表栏中,以字符串的形式
	public static String showZhanDianList(Vector resultList){
		String result="\n";
		stationinfo station=new stationinfo();
		
		for(int i=0;i<resultList.size();i++){
			station = (stationinfo)resultList.get(i);
			result=result+station.getStationName()+"\n";
		}
		
		return result;
	}
	
	//查询数据库有此站点
	public static boolean isExistZhangDian(conn_Bus db,String zhandian) throws Exception{
		boolean result=false;
		ResultSet rs=null;
		String sql="select * from stationinfo where stationName='"+zhandian+"'";
		
		rs=db.exeQuery(sql);
		if(rs.next()) result=true;
		
		return result;
	}
	
	//添加站点
	public static int addZhanDian(conn_Bus db,String zhandian,String msg[]) throws Exception{
		int result=0;
		String sql ="insert into stationinfo(stationName) values('"+zhandian+"')";
		if(!isExistZhangDian(db,zhandian)){
			result = db.exeUpdate(sql);
		}
		else{
			//插入的站点已经存在
			msg[0]="label.zhandian_insertedStationExist";  //字符串数组进行参数传递
		}
		
		
		return result;
	}
	
	//删除站点
	public static int deleteZhanDian(conn_Bus db,String zhandian,String msg[]) throws Exception{
		int result=0;
		String sql="delete from stationinfo where stationName='"+zhandian+"'";
		if(isExistZhangDian(db,zhandian)){
			result = db.exeUpdate(sql);
		}
		else{
			msg[0]="label.zhandian_deleteStationNull";
		}		
		
		return result;
	}
	
	//修改站点
	public static int modifyZhanDian(conn_Bus db,String zhandian_old,
			String zhandian_new,String msg[]) throws Exception{
		int result=0;
		String sql="update stationinfo set stationName='"+zhandian_new+"' "
		  +"where stationName='"+zhandian_old+"'";
		if(isExistZhangDian(db,zhandian_old) && !isExistZhangDian(db,zhandian_new)){
			result = db.exeUpdate(sql);
		}
		else if(!isExistZhangDian(db,zhandian_old)){
			//要修改的站点不存在,无法进行修改
			msg[0]="label.zhandian_modifyBeforeStationNull";
		}
		else if(isExistZhangDian(db,zhandian_new)){
			//修改后的站点出现重复
			msg[0]="label.zhandian_modifyAfterStationExist";
		}		
		
		return result;
	}
	
	

}