20170904_chr_filter 初试过滤器（集合模拟数据库添加图书）

filter过滤器

• /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页面</title></head><body>   <form action="AddServlet" method="post">        书名：<input type="text" name="bookName"><br>        作者：<input type="text" name="bookAuthor"><br>        定价：<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>    你添加的图书信息如下:<br>    <table>        <tr><td>书名</td><td>作者</td><td>定价</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">继续添加</a>  </body></html>