20170904_chr_filter 初試過濾器（集合模擬數據庫添加圖書）

filter過濾器

• /20170904_chr_filter/src/nuc/sw/dangdang/dao/BookDao.java

package nuc.sw.dangdang.dao;

import java.util.List;

import nuc.sw.dangdang.db.BookDB;
import nuc.sw.dangdang.vo.Book;

public class BookDao {
  public void addBook(Book b) {
     BookDB.bookList.add(b); 
  }
  public List<Book> getBooks(){
     return BookDB.bookList; 
  }
}

• /20170904_chr_filter/src/nuc/sw/dangdang/db/BookDB.java

package nuc.sw.dangdang.db;

import java.util.ArrayList;
import java.util.List;
import nuc.sw.dangdang.vo.*;

public class BookDB {
 public static List<Book> bookList=new ArrayList<Book>();
}

• /20170904_chr_filter/src/nuc/sw/dangdang/filter/Encoding.java

package nuc.sw.dangdang.filter;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;

/**
 * Servlet Filter implementation class Encoding
 */
@WebFilter("/AddServlet")
public class Encoding implements Filter {
    private String encoding;
    /**
     * Default constructor. 
     */
    public Encoding() {
        // TODO Auto-generated constructor stub
    }

    /**
     * @see Filter#destroy()
     */
    public void destroy() {
        // TODO Auto-generated method stub
    }

    /**
     * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
     */
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        // TODO Auto-generated method stub
        // place your code here
        request.setCharacterEncoding("utf-8");
        // pass the request along the filter chain
        chain.doFilter(request, response);
    }

    /**
     * @see Filter#init(FilterConfig)
     */
    public void init(FilterConfig fConfig) throws ServletException {
        // TODO Auto-generated method stub
        encoding=fConfig.getInitParameter("encoding");
    }

}

• /20170904_chr_filter/src/nuc/sw/dangdang/servlet/AddServlet.java

package nuc.sw.dangdang.servlet;

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

import nuc.sw.dangdang.dao.BookDao;
import nuc.sw.dangdang.vo.Book;

/**
 * Servlet implementation class AddServlet
 */
@WebServlet("/AddServlet")
public class AddServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    private BookDao bDao=new BookDao();   
    /**
     * @see HttpServlet#HttpServlet()
     */
    public AddServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see Servlet#init(ServletConfig)
     */
    public void init(ServletConfig config) throws ServletException {
        // TODO Auto-generated method stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request, response);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        Book book=new Book();
        //book.setBookName(request.getParameter("bookName"));
        //book.setBookAuthor(request.getParameter("bookAuthor"));
        //book.setBookPrice(Float.valueOf(request.getParameter("bookPrice")));
        //request.setAttribute("book",book);
        //request.getRequestDispatcher("showBook.jsp").forward(request, response);      
        bDao.addBook(book);
        request.setAttribute("blist", bDao.getBooks());
    }

    /**
     * @see HttpServlet#doDelete(HttpServletRequest, HttpServletResponse)
     */
    protected void doDelete(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
    }

}

• /20170904_chr_filter/src/nuc/sw/dangdang/vo/Book.java

package nuc.sw.dangdang.vo;

public class Book {
    private String bookName;
    private String bookAuthor;
    private Float bookPrice;
    public String getBookName() {
        return bookName;
    }
    public void setBookName(String bookName) {
        this.bookName = bookName;
    }
    public String getBookAuthor() {
        return bookAuthor;
    }
    public void setBookAuthor(String bookAuthor) {
        this.bookAuthor = bookAuthor;
    }
    public Float getBookPrice() {
        return bookPrice;
    }
    public void setBookPrice(Float bookPrice) {
        this.bookPrice = bookPrice;
    }

}

• /20170904_chr_filter/WebContent/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>20170904_chr_filter</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
</web-app>

• /20170904_chr_filter/WebContent/addBook.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>添加Book頁面</title>
</head>
<body>
   <form action="AddServlet" method="post">
        書名：<input type="text" name="bookName"><br>
        作者：<input type="text" name="bookAuthor"><br>
        定價：<input type="text" name="bookPrice"><br>   
    <input type="submit" value="提交"><br>
   </form>
</body>
</html>

• /20170904_chr_filter/WebContent/showBook.jsp

<%@ page language="java"  contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ page import="java.util.*,nuc.sw.dangdang.vo.Book" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
  <body>
    你添加的圖書信息如下:<br>
    <table>
        <tr><td>書名</td><td>作者</td><td>定價</td></tr>
        <%
            Iterator<Book> iter=((ArrayList<Book>)session.getAttribute("bList")).iterator();
            while(iter.hasNext()){
                pageContext.setAttribute("b", iter.next());
            %>
            <tr>
                <td>${b.bookName }</td>
                <td>${b.bookAuthor }</td>
                <td>${b.bookPrice }</td>
            </tr>
            <%} %>
    </table> 
    <a href="addBook.jsp">繼續添加</a>
  </body>
</html>