서블릿에서 JSP 페이지로 데이터 전송

서블릿에서 printWriter 코드를 제거하고 싶습니다.서블릿에서 JSP 페이지로 데이터 전송

기본적으로 현재 고객과 해당 도시를 색인 페이지의 숨겨진 필드 인 id로 출력하려고합니다. 거기에서 고객 이름이나 도시를 편집 한 다음 정보가 업데이트 될 인덱스 페이지로 다시 보내도록하고 싶습니다.

어떻게하면됩니까?

서블릿

package edu.witc.Assignment02.controller; 

import java.io.IOException; 
import java.io.PrintWriter; 
import java.util.ArrayList; 
import java.util.List; 

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 edu.witc.Assignment02_model.*; 

/** 
* Servlet implementation class CustomerServlet 
*/ 
@WebServlet(name = "CustomerServlet", urlPatterns = { 
     "/customer", "/editCustomer", "/updateCustomer" 
}) 
public class CustomerServlet extends HttpServlet { 
    private static final long serialVersionUID = -20L; 

    private List<Customer> customers = new ArrayList<Customer>(); 


    /** 
    * @see HttpServlet#HttpServlet() 
    */ 
    public CustomerServlet() { 
     super(); 
     // TODO Auto-generated constructor stub 
    } 

    @Override 
    public void init() throws ServletException { 
     Customer customer1 = new Customer(); 
     customer1.setId(1); 
     customer1.setName("Donald D."); 
     customer1.setCity("Miami"); 
     customer1.add(customer1); 

     Customer customer2 = new Customer(); 
     customer1.setId(2); 
     customer1.setName("Mickey M."); 
     customer1.setCity("Orlando"); 
     customer1.add(customer2); 
    } 

    private void sendCustomerList(HttpServletResponse response) throws IOException { 
     response.setContentType("text/html"); 
     PrintWriter writer = response.getWriter(); 
     writer.println("<html><head><title>Customers</title></head>" 
       + "<body><h2>Custoemrs</h2>"); 
     writer.println("<ul>"); 
     for (Customer customer : customers){ 
      writer.println("<li>" + customer.getName() 
        + "(" + customer.getCity() + ") (" 
        + "<a href='editCustomer?id=" + customer.getId() 
        + ";>edit</a>)"); 
     } 
     writer.println("</ul>"); 
     writer.println("</body></html>"); 
    } 

    private Customer getCustomer(Integer customerId){ 
     for (Customer customer : customers) { 
      if(customer.getId() == customerId){ 
       return customer; 
      } 
     } 
     return null; 
    } 

    private void sendEditCustomerForm(HttpServletRequest request, HttpServletResponse response) throws IOException { 
     response.setContentType("text/html"); 
     PrintWriter writer = response.getWriter(); 
     Integer customerId = 0; 
     try{ 
      customerId = Integer.parseInt(request.getParameter("id")); 
     }catch(NumberFormatException e){ 

      } 
     Customer customer = getCustomer(customerId); 

     if(customer != null){ 
      writer.println("<html><head>" 
        + "<title>Edit Customer</title></head>" 
        + "<body><h2>Edit Customer</h2>" 
        + "<form method = 'post' action = 'updateCustomer'>"); 
      writer.println("<input type = 'hidden' name = 'id' value = 'customerId'/>"); 
      writer.println("<table>"); 
      writer.println("<tr><td>Name:</td><td>" 
        + "<input name = 'name' value = '" 
        + customer.getName().replaceAll("'", "&#39") 
        + "'/></td></tr>"); 
      writer.println("<tr><td>City:</td><td>" 
        + "<input name = 'city' value = '" 
        + customer.getCity().replaceAll("'", "&#39") 
        + "'/></td></tr>"); 
      writer.println("<tr>" 
        + "<td colspan='2' style = 'text-align: right'>" 
        + "<input type ='submit' value = 'Update'/></td>" 
        + "</tr>"); 
      writer.println("<tr><td colspan='2'>" 
        + "<a href = 'customer'>CustomerList</a>" 
        + "</td></tr>"); 
      writer.println("</table>"); 
      writer.println("</form></body>"); 
     }else{ 
      writer.println("No Customer Found"); 

     } 
     } 

    @Override 
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
     String uri = request.getRequestURI(); 
     if(uri.endsWith("/customer")){ 
      sendCustomerList(response); 
     }else if(uri.endsWith("/editCustomer")){ 
      sendEditCustomerForm(request, response); 
     } 
    } 

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
     //update customer 
     Integer customerId = 0; 
     try{ 
      customerId = Integer.parseInt(request.getParameter("id")); 
     }catch(NumberFormatException e){ 

     } 
     Customer customer = getCustomer(customerId); 
     if(customer != null){ 
      customer.setName(request.getParameter("name")); 
      customer.setCity(request.getParameter("city")); 
     } 
     sendCustomerList(response); 
    } 

}

고객 클래스

package edu.witc.Assignment02_model; 

    public class Customer { 
     private Integer id; 
     private String name; 
     private String city; 

     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 getCity(){ 
      return city; 
     } 

     public void setCity(String city){ 
      this.city = city; 
     } 

     public void add(Customer customer1) { 
      // TODO Auto-generated method stub 

     } 

    }

인덱스 페이지

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" 
    pageEncoding="ISO-8859-1"%> 
<!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=ISO-8859-1"> 
<title>Home</title> 
</head> 
<body> 
<h1>Current Customer(s) w/City</h1><br> 
<%! String name, city; %> 

<% %> 






</body> 
</html>

출처

2014-02-09 user2939808

더 나은 늦게 일 절대로.

이 기능을 사용하려면 jstl 라이브러리를 프로젝트에 추가해야합니다.

서블릿

@WebServlet(name = "CustomerServlet", urlPatterns = { 
     "/customer", "/editCustomer", "/updateCustomer" 
}) 
public class CustomerServlet extends HttpServlet { 
    private static final long serialVersionUID = -20L; 

    private List<Customer> customers = new ArrayList<Customer>(); 

    @Override 
    public void init() throws ServletException { 
     Customer customer1 = new Customer(); 
     ... 
     customers.add(customer1); 

     Customer customer2 = new Customer(); 
     ... 
     customers.add(customer2); 
    } 

    private Customer getCustomer(Integer customerId){ 
     for (Customer customer : customers) { 
      if(customer.getId() == customerId){ 
       return customer; 
      } 
     } 
     return null; 
    } 


    @Override 
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
     String uri = request.getRequestURI(); 
     if(uri.endsWith("/customer")){ 

      request.setAttribute("customers", customers); 
      request.getRequestDispatcher("/customers.jsp").forward(request, response); 

     }else if(uri.endsWith("/editCustomer")){ 

      try{ 
       customerId = Integer.parseInt(request.getParameter("id")); 
      }catch(NumberFormatException e){ 
       e.printStackTrace(); 
      } 
      Customer customer = getCustomer(customerId); 

      request.setAttribute("customer", customer); 
      request.getRequestDispatcher("/edit_customer.jsp").forward(request, response); 

     } 
    } 

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 

     Integer customerId = 0; 
     try{ 
      customerId = Integer.parseInt(request.getParameter("id")); 
     }catch(NumberFormatException e){ 

     } 
     Customer customer = getCustomer(customerId); 
     if(customer != null){ 
      customer.setName(request.getParameter("name")); 
      customer.setCity(request.getParameter("city")); 
     } 
     response.sendRedirect("/customer"); 
    } 

}

customers.jsp

<%@page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" session="false" %> 
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 

<h1>Customer list</h1> 

<ul> 
<c:forEach var="c" items="${customers}"> 
    <li>${c.name} (<a href="editCustomer?id=${c.id}">Edit</a>)</li> 
</c:forEach> 
</ul>

edit_customer.jsp

<%@page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" session="false" %> 
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 

<h1>Edit customer</h1> 

<form method="POST" action="/updateCustomer"> 
    <input type="hidden" name="id" value="${customer.id}"/> 
    Name: <input type="text" name="name" value="${customer.name}"/><br/> 
    City: <input type="text" name="city" value="${customer.city}"/><br/> 
    <input type="submit" value="Save"/> 

</form>

출처

2014-02-09 04:55:59

안녕하세요 덕분에 무리 ... 유일한 것은 내가 그나마 g et는 $ {customer.name} 등입니다. 이를 수행 할 확장 된 방법이 있거나 광고 주석을 달 수 있습니까? Thanks – user2939808

$ {customer}는 서블릿에서 jsp로 전달되는 요청 속성입니다. "request.setAttribute ("customer ", customer);" 이름, 도시 - 고객 객체의 필드를 가져 오려면 Customer 객체에 getters/setters 메소드가 있어야합니다. –

taglib이 작동하지 않는다고 말하는 웬일인지 – user2939808

서블릿에서 JSP 페이지로 데이터 전송

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