圖書資訊查詢系統

分層結構

util包

DButil程式碼

package top.xinsir.util;

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

public class DBUtil {
	static{
		try {
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static Connection getConn(){
		Connection conn = null;
		try {
			conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=MyDB", "sa", "1");
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		return conn;
	}
	
	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) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

bean包

Book.java程式碼

package top.xinsir.bean;

public class Book {
	private Integer id;
	private String name;
	private String isbn;
	private Float price;
	private String author;
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getIsbn() {
		return isbn;
	}
	public void setIsbn(String isbn) {
		this.isbn = isbn;
	}
	public Float getPrice() {
		return price;
	}
	public void setPrice(Float price) {
		this.price = price;
	}
	public String getAuthor() {
		return author;
	}
	public void setAuthor(String author) {
		this.author = author;
	}
	public Book(Integer id, String name, String isbn, Float price, String author) {
		super();
		this.id = id;
		this.name = name;
		this.isbn = isbn;
		this.price = price;
		this.author = author;
	}
	public Book(String name, String isbn, Float price, String author) {
		super();
		this.name = name;
		this.isbn = isbn;
		this.price = price;
		this.author = author;
	}
	public Book() {
		super();
		// TODO Auto-generated constructor stub
	}
	@Override
	public String toString() {
		return "<tr>"
				+"<td>"+id+"</td>"
				+"<td>"+name+"</td>"
				+"<td>"+isbn+"</td>"
				+"<td>"+price+"</td>"
				+"<td>"+author+"</td>"
			+"</tr>";
	}
}

action包

BookSearchServlet.java程式碼

package top.xinsir.action;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import top.xinsir.bean.Book;
import top.xinsir.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 {
		// 設定編碼
		request.setCharacterEncoding("UTF-8");
		// 獲取引數
		String bookName = request.getParameter("bookName");
		
		// 獲取傳遞過來的Book物件
		Book book = BookTest.getBookByName(bookName);
		
		// 將圖書資訊顯示在bookInfo.jsp頁面
		request.setAttribute("book", book);
		request.getRequestDispatcher("bookInfo.jsp").forward(request, response);
	}

}

web.xml設定

<?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.xinsir.action.BookSearchServlet</servlet-class>
  </servlet>

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

test包

BookTest.java程式碼

package top.xinsir.test;

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

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

public class BookTest {
	public static Book getBookByName(String bookName){
		// 連線資料庫並且把資料查詢出來 儲存在book物件中，最後返回book物件即可
		Connection conn = null;
		PreparedStatement ps = null;
		ResultSet rs = null;
		
		// 查詢程式碼
		conn = DBUtil.getConn();// 載入驅動
		String sql = "select * from book where name=?";//準備sql語句
		Book book = new Book();// 範例化Book物件
		try {
			ps = conn.prepareStatement(sql);
			// 設定值
			ps.setString(1, bookName);
			rs = ps.executeQuery();
			
			if(rs.next()){
				// 如果判斷查詢到值得話賦值到book物件中
				book = new Book();// 重新範例化Book物件
				// 設定book裡的值
				book.setId(rs.getInt("id"));
				book.setName(rs.getString("name"));
				book.setIsbn(rs.getString("isbn"));
				book.setPrice(rs.getFloat("price"));
				book.setAuthor(rs.getString("author"));
			}else{
				// 如果沒有查詢到內容給的話book為空值
				book = null;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		// 關閉資源
		DBUtil.close(conn, ps, rs);
		// 返回book物件
		return book;
	}
}

WebRoot下jsp頁面

search.jsp頁面

<%@ 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 'search.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>
  <%
  	// 如果沒有該圖書返回一個msg值 接收該值
  	String msg = (String)request.getAttribute("msg");
  	if(msg==null)
  		msg="";
   %>
    <form action="bookSearch" method="post">
    	圖書名稱:<input type="text" name="bookName" /><span style="color: red"><%=msg %></span><br>
    	<input type="submit" value="查詢" />
    </form>
  </body>
</html>

bookInfo.jsp頁面

<%@page import="top.xinsir.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 'bookInfo.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">
	-->
	<style type="text/css">
		table{
			margin: 0 auto;
		}
		h1{
			text-align: center;
			color: red;
		}
		td{
			text-align: center;
		}
		.id,.price{
			width: 60px;
		}
		.name,.author{
			width: 100px;
		}
		.isbn{
			width: 250px;
		}
	</style>
</head>

<body>
	<%
		// 接收Book值
		Book book = (Book) request.getAttribute("book");
		// 如果book的值不是空值得話 列印出來圖書資訊
	%>
	<h1>查詢結果</h1>
	<table border="1" cellpadding="0" cellspacing="0">
		<tr>
			<th class="id">id</th>
			<th class="name">書籍名稱</th>
			<th class="isbn">ISBN</th>
			<th class="price">價錢</th>
			<th class="author">作者</th>
		</tr>
	<%
		if (book != null) {
			out.println(book.toString() + "<br>");
		} else {
			// 如果為空值的話說明沒有這個圖書資訊
			request.setAttribute("msg", "很抱歉,沒有查詢到該圖書");
			// 繼續轉發到search.jsp頁面
			request.getRequestDispatcher("search.jsp").forward(request,
					response);
		}
	%>
	</table>
</body>
</html>

book表資料

瀏覽器效果

search.jsp頁面

輸入資料庫沒有的資料之後

點選查詢

輸入資料庫中已有的資料之後

點選查詢之後

這樣一個圖書查詢系統就算完成了