authorservice.java

一套网上书店系统采用JAVABEAN+SERVLET+JSP

package cn.dang.service;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import cn.dang.dao.AllDAO;
import cn.dang.entity.Author;
import cn.dang.entity.Book;
import cn.dang.entity.Type;

public class AuthorService {
	private AllDAO allDAO=new AllDAO();
	
	public int getAuthorIdByName(String authorName) throws Throwable{
		//查询作者信息所需的SQL语句
		String sql="select aid from author where authorname='"+authorName+"'";
		//从DAO层获得信息
		List list=allDAO.getAuthorDAO().queryAuthor(sql);
		Author author=new Author();
		//如果list大于0说明有数据，则进行数据封装
		if(list.size()>0){
			return (Integer.parseInt(((String[])list.get(0))[0]));
		}
		return 0;
	}
	
	public int setAuthorInfo(ArrayList values_list) throws Throwable{
		//设置插入数据所需要的SQL语句
		String sql="insert into author(authorname,introduction) values(?,'')";
		//调用DAO层插入信息
		allDAO.getAuthorDAO().nonQueryAuthor(sql, values_list);
		//返回ID
		return this.getAuthorId(values_list.get(0).toString());
	}
	
	private int getAuthorId(String authorName) throws Throwable{
		//设置查询数据所需的SQL语句
		int aid=allDAO.getAuthorDAO().queryAuthorId("select aid from author where authorname='"+authorName+"'");
		return aid;
	}
	//更新出表名字信息
	public void updateAuthor(ArrayList values_list) throws Throwable{
		String sql="update author set authorname=? where aid=?";
		allDAO.getAuthorDAO().nonQueryAuthor(sql, values_list);
	}
	
	// 操作作者信息方法
	public int getAuthorIdByName(ArrayList values_list)
			throws Throwable {
		// 获得保存在ArrayList中的authorName
		String authorName = values_list.get(0).toString();
		// 如果不存在这个作者就进行添加,并将Aid保存在对象中
		int aid = this.getAuthorIdByName(authorName);
		if (aid == 0) {
			aid=this.setAuthorInfo(values_list);
		}
		//返回ID值一边进行保存
		return aid;
	}
	
	public int getAuthorIdByNameAndUpdate(ArrayList values_list) throws Throwable{
		// 获得保存在ArrayList中的authorName
		System.out.println(values_list.get(0).toString());
		String authorName = values_list.get(0).toString();
		// 如果不存在这个作者就进行添加,并将Aid保存在对象中
		int aid = this.getAuthorIdByName(authorName);
		if (aid == 0) {
			aid=this.setAuthorInfo(values_list);
		}else{
			values_list.add(aid);
			this.updateAuthor(values_list);
		}
		//返回ID值一边进行保存
		return aid;
	}
	
	// 查询作者表的信息
	public Author getAuthorInfo(int id) throws Throwable {
		String sql = "select * from author where aid=" + id;
		return allDAO.getAuthorDAO().queryAuthorInfo(sql);
	}
	
	
}