booktypedao.java

基于sturts的图书管理系统

package com.dao;

import com.core.ConnDB;
import java.sql.*;
import java.util.*;
import com.actionForm.BookTypeForm;

public class BookTypeDAO {
	private ConnDB conn = new ConnDB();

	// 查询数据
	public Collection query(String strif) {
		BookTypeForm bookTypeForm = null;
		Collection bookTypeColl = new ArrayList();
		String sql = "";
		if (strif != "all" && strif != null && strif != "") {
			sql = "select * from tb_bookType where " + strif + "";
		} else {
			sql = "select * from tb_bookType";
		}
		ResultSet rs = conn.executeQuery(sql);
		try {
			while (rs.next()) {
				bookTypeForm = new BookTypeForm();
				bookTypeForm.setId(Integer.valueOf(rs.getString(1)));
				bookTypeForm.setTypeName(rs.getString(2));
				bookTypeForm.setDays(rs.getInt(3));
				bookTypeColl.add(bookTypeForm);
				System.out.print(bookTypeForm.getTypeName());
			}
		} catch (SQLException ex) {
		}
		conn.close();
		return bookTypeColl;
	}

	// 用于修改的查询
	public BookTypeForm queryM(BookTypeForm bookTypeForm) {
		BookTypeForm bookTypeForm1 = null;
		String sql = "select * from tb_bookType where id="
				+ bookTypeForm.getId() + "";
		System.out.println("修改时的SQL：" + sql);
		ResultSet rs = conn.executeQuery(sql);
		try {
			while (rs.next()) {
				bookTypeForm1 = new BookTypeForm();
				bookTypeForm1.setId(Integer.valueOf(rs.getString(1)));
				bookTypeForm1.setTypeName(rs.getString(2));
				bookTypeForm1.setDays(rs.getInt(3));
			}
		} catch (SQLException ex) {
		}
		conn.close();
		return bookTypeForm1;
	}

	// 添加数据图书类别信息
	public int insert(BookTypeForm bookTypeForm) {
		/*首先查询该图书类别名称是否已经存在*/
		String sql1 = "SELECT * FROM tb_bookType WHERE typename='"
				+ bookTypeForm.getTypeName() + "'";
		ResultSet rs = conn.executeQuery(sql1);
		String sql = "";
		int falg = 0;
		try {
			if (rs.next()) {/*如果该图书类别名称存在,返回2*/
				falg = 2;
			} else {
				sql = "Insert into tb_bookType (typename,days) values('"
						+ bookTypeForm.getTypeName() + "',"
						+ bookTypeForm.getDays() + ")";
				falg = conn.executeUpdate(sql);
				System.out.println("添加图书类型的SQL：" + sql);
				conn.close();
			}
		} catch (SQLException ex) {
			falg = 0;
		}
		System.out.println("falg:" + falg);
		return falg;
	}

	// 修改数据
	public int update(BookTypeForm bookTypeForm) {
		String sql = "Update tb_bookType set typename='"
				+ bookTypeForm.getTypeName() + "',days="
				+ bookTypeForm.getDays() + " where id=" + bookTypeForm.getId()
				+ "";
		int falg = conn.executeUpdate(sql);
		System.out.println("修改数据时的SQL：" + sql);
		conn.close();
		return falg;
	}

	// 删除数据
	public int delete(BookTypeForm bookTypeForm) {
		String sql_1 = "SELECT * FROM tb_bookinfo WHERE typeid="
				+ bookTypeForm.getId() + "";
		ResultSet rs = conn.executeQuery(sql_1);
		int falg = 0;
		try {
			if (!rs.next()) {
				String sql = "Delete from tb_bookType where id="
						+ bookTypeForm.getId() + "";
				falg = conn.executeUpdate(sql);
				System.out.println("删除时的SQL：" + sql);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return falg;
	}
}