bean.java

用servlet做的多表的简单增删改查,数据库是用sql2

package bean;

import java.sql.SQLException;
import java.util.HashMap;
import java.util.List;

import persistence.DataBaseConnection;

public class Bean {
	
	public void executeUpdate(String sql){
		DataBaseConnection dbc=new DataBaseConnection();
		dbc.createConnection();
		dbc.executeUpdate(sql);
		dbc.commit();
		dbc.closeDBConnection();
	}
	
	public HashMap queryMap(String sql){
		DataBaseConnection dbc=new DataBaseConnection();
		dbc.createConnection();
		HashMap hash=null;
		try {
			 hash=dbc.executeQueryForMap(sql);
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		dbc.closeDBConnection();
		return hash;
	}
	
	public void insertRelation(List list){
		DataBaseConnection dbc=new DataBaseConnection();
		dbc.createConnection();
		dbc.executeUpdateBatch(list);
		dbc.commit();
		dbc.closeDBConnection();
	}
	
	public List queryList(String sql){
		DataBaseConnection dbc=new DataBaseConnection();
		dbc.createConnection();
		List list=null;
		try {
			list=dbc.executeQueryForList(sql);
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return list;
	}

}