图书信息查询系统

package top.gaojc.action;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import top.gaojc.bean.Book;
import top.gaojc.test.BookTest;

public class BookSearchServlet extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doPost(request, response);
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		// 1.设置编码
		request.setCharacterEncoding("utf-8");
		
		// 2.获取参数
		String bookName = request.getParameter("bookName");
		Book book = BookTest.getBookByName(bookName);
				
		// 3.将图书信息显示在bookInfo.jsp的页面
		request.setAttribute("book", book);
		request.getRequestDispatcher("bookInfo.jsp").forward(request, response);
	}
}

package top.gaojc.bean;

public class Book {
	
	private int id;
	private String bookName;
	private String author;
	private String classify;
	private float price;
	
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getBookName() {
		return bookName;
	}
	public void setBookName(String bookName) {
		this.bookName = bookName;
	}
	public String getAuthor() {
		return author;
	}
	public void setAuthor(String author) {
		this.author = author;
	}
	public String getClassify() {
		return classify;
	}
	public void setClassify(String classify) {
		this.classify = classify;
	}
	public float getPrice() {
		return price;
	}
	public void setPrice(float price) {
		this.price = price;
	}
	
	public Book() {
		super();
		// TODO Auto-generated constructor stub
	}
	
	public Book(int id, String bookName, String author, String classify,
			float price) {
		super();
		this.id = id;
		this.bookName = bookName;
		this.author = author;
		this.classify = classify;
		this.price = price;
	}
	
	@Override
	public String toString() {
		return "<tr>"
				+"<td><center>"+id+"</center></td>"
				+"<td><center>"+bookName+"</center></td>"
				+"<td><center>"+author+"</center></td>"
				+"<td><center>"+classify+"</center></td>"
				+"<td><center>"+price+"</center></td>"
			+"</tr>";
	}
}

package top.gaojc.test;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import top.gaojc.bean.Book;
import top.gaojc.util.DBUtil;

public class BookTest {
	public static Book getBookByName(String bookName) {
		// 连接数据库并且把数据查询出来 存储在book对象中，最后返回book对象即可

		// 1 2 调用DBUtil方法添加驱动程序包、连接数据库
		Connection conn = DBUtil.getConn();

		// 3.添加sql语句
		String sql = "select * from book where bookName = ?";

		// 4.准备一个和数据库打交道的
		PreparedStatement ps = null;
		ResultSet rs = null;
		Book book = null;
		try {
			ps = conn.prepareStatement(sql);
			ps.setString(1, bookName);
			// 5.查询结果
			rs = ps.executeQuery();
			if (rs.next()) {
				// 创建一个有属性值的对象
				// 6.输出
				book = new Book(rs.getInt(1), rs.getString(2), rs.getString(3),rs.getString(4), rs.getFloat(5));
			}
		} catch (Exception e) {
			// TODO: handle exception
		} finally {
			// 7.调用DBUtil关闭资源
			DBUtil.close(conn, ps, rs);
		}
		// 返回值
		return book;
	}
}

package top.gaojc.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DBUtil {
	
	// 1.添加驱动程序包
	static {
		try {
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}

	// 2.连接数据库
	public static Connection getConn() {
		Connection conn = null;
		try {
			// ("jdbc:运行环境://localhost:端口号;databaseName=数据库名称","SQL账号","SQL密码")
			conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=bookwork","sa", "1");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}

	// 7.关闭资源
	public static void close(Connection conn, PreparedStatement ps, ResultSet rs) {
		try {
			if (conn != null)
				conn.close();

			if (ps != null)
				ps.close();

			if (rs != null)
				rs.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
	xmlns="http://java.sun.com/xml/ns/javaee" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <display-name></display-name>
  <servlet>
    <description>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>BookSearchServlet</servlet-name>
    <servlet-class>top.gaojc.action.BookSearchServlet</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>BookSearchServlet</servlet-name>
    <url-pattern>/BookSearchServlet</url-pattern>
  </servlet-mapping>	
  <welcome-file-list>
    <welcome-file>search.jsp</welcome-file>
  </welcome-file-list>
</web-app>

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
	String path = request.getContextPath();
	String basePath = request.getScheme() + "://"
			+ request.getServerName() + ":" + request.getServerPort()
			+ path + "/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">

<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
	<link rel="stylesheet" type="text/css" href="styles.css">
	-->
</head>

<body>
	<form action="BookSearchServlet" method="post">
		图书名称：
		<input type="text" name="bookName">
		<input type="submit"value="查询">
	</form>
</body>
</html>

<%@page import="top.gaojc.bean.Book"%>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
	String path = request.getContextPath();
	String basePath = request.getScheme() + "://"
			+ request.getServerName() + ":" + request.getServerPort()
			+ path + "/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">

<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
	<link rel="stylesheet" type="text/css" href="styles.css">
	-->
</head>

<body>
	<%
		// 接收Book值
		Book book = (Book) request.getAttribute("book");
	%>

	<h1 style=text-align:center;>查询结果</h1>
	<table border="1" cellpadding="0" cellspacing="0" align="center" width="600px">
		<tr>
			<td><center>编号</center></td>
			<td><center>图书名称</center></td>
			<td><center>作者</center></center></td>
			<td><center>类别</center></td>
			<td><center>价格</center></td>
		</tr>
		
		<%
			if (book != null) {
				// 如果book的值不是空值 打印出来图书信息
				out.println(book.toString() + "<br>");
			} else {
				// 如果为空值的话继续跳转到search.jsp页面
				request.getRequestDispatcher("search.jsp").forward(request,response);
			}
		%>
	</table>
</body>
</html>