classdao.java

一套购物车项目。电子商务系统。实现了前台和后台的业务逻辑。

package com.softfz.jn0708.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import com.softfz.jn0708.bean.ClassBean;
import com.softfz.jn0708.util.SqlUtil;

/**
 * 商品类别管理操作的DAO
 * 
 * @author admin
 *
 */
public class ClassDAO {
	/**
	 * 获取大类 列表
	 * @return
	 */
	public List getBclass() {
		String sql = "select * from T_classinfo where parentid=0";
		Connection conn = null;
		Statement st = null;
		ResultSet rs = null;
		conn = SqlUtil.getConn();
		List list = null;
		try {
			st = conn.createStatement();
			rs = st.executeQuery(sql);
			list = new ArrayList();
			ClassBean info = null;
			while (rs.next()) {
				info = new ClassBean();
				info.setClassid(rs.getInt("classid"));
				info.setClassname(rs.getString("classname"));
				info.setParentid(rs.getInt("parentid"));
				list.add(info);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			SqlUtil.tryClose(rs, st, conn);
		}

		return list;
	}

	/**
	 * 获取小类 列表
	 * @return
	 */
	public List getNclass() {
		String sql = "select * from T_classinfo where parentid!=0";
		Connection conn = null;
		Statement st = null;
		ResultSet rs = null;
		conn = SqlUtil.getConn();
		List list = null;
		try {
			st = conn.createStatement();
			rs = st.executeQuery(sql);
			list = new ArrayList();
			ClassBean info = null;
			while (rs.next()) {
				info = new ClassBean();
				info.setClassid(rs.getInt("classid"));
				info.setClassname(rs.getString("classname"));
				info.setParentid(rs.getInt("parentid"));
				list.add(info);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			SqlUtil.tryClose(rs, st, conn);
		}

		return list;
	}
	


	/**
	 * 添加商品类别时候   判断该商品类别是否有被用
	 * @param name 商品名称
	 * @param parentid 商品ID
	 * @return
	 */
	public boolean isUsed(String name,String parentid) {
		Connection conn = SqlUtil.getConn();
		PreparedStatement ps = null;
		ResultSet rs = null;
		String Sql = null;
		boolean flag = false;
		if (conn != null){
			if(parentid!=null && parentid.equals("0")){
				Sql="select * from T_classinfo where classname=? and parentid = '0'";
			}else{
				Sql="select * from T_classinfo where classname=? and parentid!='0'";
			}
			try {
				ps = conn.prepareStatement(Sql);
				ps.setString(1,name);
				rs = ps.executeQuery();
				if(rs.next()){
					flag = true;
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}finally{
				SqlUtil.tryToClose(rs,ps,conn);
			}
		}
		return flag;
	}
	
	/**
	 * 修改商品类别时候   判断该商品类别是否有被用
	 * @param name 商品名称
	 * @param classid 商品ID
	 * @param parentid 商品类别父ID
	 * @return
	 */

	public boolean isUsing(String name,String classid ,String parentid) {
		Connection conn = SqlUtil.getConn();
		PreparedStatement ps = null;
		ResultSet rs = null;
		String Sql = null;
		boolean flag = false;
		if (conn != null){
			if(parentid!=null && parentid.equals("0")){
				Sql="select * from T_classinfo where classname=? and classid!=? and parentid = '0'";
			}else{
				Sql="select * from T_classinfo where classname=? and classid!=? and parentid!='0'";
			}
			try {
				ps = conn.prepareStatement(Sql);
				ps.setString(1,name);
				ps.setString(2,classid);
				rs = ps.executeQuery();
				if(rs.next()){
					flag = true;
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}finally{
				SqlUtil.tryToClose(rs,ps,conn);
			}
		}
		return flag;
	}

	
	
	/**
	 * 根据类别编号获取类别信息
	 * @param classid 商品类别ID
	 * @return
	 */


	public ClassBean getClassType(String classid) {
		ClassBean classBean = null;
		Connection conn = SqlUtil.getConn();
		PreparedStatement ps = null;
		ResultSet rs = null;
		if(conn!=null){
			if(classid!=null && !classid.trim().equals("")){
				String Sql = "select * from t_classinfo where classid=?";
				try {
					ps = conn.prepareStatement(Sql);
					ps.setString(1, classid);
					rs = ps.executeQuery();
					classBean = new ClassBean();
					if (rs.next()) {
						classBean.setClassid(Integer.parseInt(rs.getString("classid").trim()));
						classBean.setClassname(rs.getString("classname"));
						classBean.setParentid(Integer.parseInt(rs.getString("parentid").trim()));
					}
				} catch (SQLException e) {
					e.printStackTrace();
				} finally {
					SqlUtil.tryToClose(rs, ps, conn);
				}
			}
		}
		return classBean;
	}	
	

	
	/**
	 * 根据类别编号删除类别
	 * @param classid 大类ID
	 * @param parentid 夫类ID
	 * @return
	 */
	public boolean delClassType(String classid,String parentid) {
		
			if(parentid!=null && parentid.equals("0")){
				String[] sqlStr = new String[2]; 
				sqlStr[0]="delete t_iteminfo where classid="+classid;
				sqlStr[1]="delete t_classinfo where classid ="+classid+" or  parentid ="+ classid;
				return SqlUtil.executeUpdates(sqlStr);
				
			}else{
				String[] sqlStr = new String[2]; 
				sqlStr[0]="delete t_iteminfo where nclassid="+classid;
				sqlStr[1]="delete from t_classinfo where classid ="+classid;
				return SqlUtil.executeUpdates(sqlStr);
			}
							

	}
	
	
	/**
	 * 修改商品类别信息
	 * @param classBean 商品类别Bean对象
	 * @return
	 */
	public boolean updateClassType(ClassBean classBean) {
		Connection conn = SqlUtil.getConn();
		PreparedStatement ps = null;
		ResultSet rs = null;
		String Sql = null;
		boolean flag = false;
		try {
			if (classBean != null) {
				Sql = "update t_classinfo set classname=? where classid=?";
				ps = conn.prepareStatement(Sql);
				ps.setString(1, classBean.getClassname());
				ps.setInt(2, classBean.getClassid());
				int i = ps.executeUpdate();
				if (i > 0) {
					flag = true;
				}
			}

		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			SqlUtil.tryToClose(rs, ps, conn);
		}
		return flag;
	}
	
	/**
	 * 增加商品类别信息
	 * @param classBean商品类别Bean对象
	 * @return
	 */
	public boolean addClassType(ClassBean classBean){
		Connection conn = SqlUtil.getConn();
		PreparedStatement ps = null;
		ResultSet rs = null;
		String Sql = null;
		boolean flag = false;
		if (conn != null){
			Sql="insert into t_classinfo(classid,classname,parentid)";
			Sql = Sql+" values(SEQ_T_CLASSINFO.NEXTVAL,?,?)";
			try {
				ps = conn.prepareStatement(Sql);
				ps.setString(1,classBean.getClassname());
				ps.setInt(2,classBean.getParentid());
				int i = ps.executeUpdate();
				if(i>0){
					flag = true;
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}finally{
				SqlUtil.tryToClose(rs,ps,conn);
			}
		}
		return flag;
	}	
	
		
	
}