basedao.java

servlet实现网上书店查询

package com.ghy.base.dao;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import com.ghy.util.DataManager;
import com.ghy.util.DataManagerFactory;

public class BaseDao {
	private DataManager datamanager;
	public DataManager getDatamanager()
	{
		if(this.datamanager==null)
		
			this.setDatamanager(DataManagerFactory.getDataBaseManager());
		return datamanager;
		
	}
	public void setDatamanager(DataManager datamanager)
	{
		this.datamanager=datamanager;
	}
	
	public String generateId(Connection conn) throws SQLException
	{
		//dual是oracle系统里的一个伪表,一行一列
		//UIDSEQ.NEXTVAL
		String sql = "select UIDSEQ.NEXTVAL FROM DUAL";
		Statement stat=conn.createStatement();
		ResultSet rt=stat.executeQuery(sql);
		rt.next();
		String id =rt.getString(1);
		return id;
	}

}