【JSP】【Servlet】 Servlet で 確認ダイアログ を表示させるには...

Java / その他Web関連

サンプル

http://oshiete.goo.ne.jp/qa/1203828.html
にある <body>タグで「onLoad」イベントを利用して確認ダイアログを表示させる。

■ 画面側

main.jsp

* checkboxを付けてボタン押下すれば確認ダイアログが表示する 
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<jsp:useBean id="sampleBean" class="com.sample.SampleBean" scope="request" />
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "">http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script type="text/javascript">
<!--
function showConfirmDialog(){
   if(confirm("Are you really sure to delete data?")){
     window.location='./ok.html';
     return;
   }
}
//-->
</script> 
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
</head>
<body
<%if(sampleBean.needToShowConfirmDialog()) { %>
onload="showConfirmDialog()"
<%} %>
>
<form action="<%=request.getContextPath() %>/CheckServlet" method="post">
<input type="checkbox" id="ShowDialog" name="ShowDialog" value="true"><br />
<input type="submit" value="Go To Servlet"><br />
</form>
</body>
</html>

ok.html

* 最終移動先 
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Sample</title>
</head>
<body>
OK!
</body>
</html>

■ Java側

CheckServlet.java

* Servlet 
import java.io.IOException;

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

import com.sample.SampleBean;

/**
 * Servlet implementation class CheckServlet
 */
public class CheckServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;

   /**
    * @see HttpServlet#HttpServlet()
    */
   public CheckServlet() {
      super();
   }

   /**
    * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    */
   protected void doGet(HttpServletRequest request, HttpServletResponse response)
         throws ServletException, IOException {
      String showDialog = request.getParameter("ShowDialog");
      SampleBean sampleBean = new SampleBean();
      if (this.toBoolean(showDialog)) {
         sampleBean.setNeedToShowConfirmDialog(true);
      } else {
         sampleBean.setNeedToShowConfirmDialog(false);
      }

      request.setAttribute("sampleBean", sampleBean);
      RequestDispatcher requestDispatcher = request.getRequestDispatcher("./Views/main.jsp");
      requestDispatcher.forward(request, response);
   }

   /**
    * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    */
   protected void doPost(HttpServletRequest request,
         HttpServletResponse response) throws ServletException, IOException {
      this.doGet(request, response);
   }
   
   private boolean toBoolean(String value) {
      try {
         return Boolean.valueOf(value);
      } catch (Exception ex) {
      }
      return false;
   }
}

com.sample.SampleBean.java

* Servletと画面側間のデータ 
package com.sample;

import java.io.Serializable;

public class SampleBean implements Serializable {
   private static final long serialVersionUID = 1L;
   private boolean needToShowConfirmDialog;

   public SampleBean() {
      this.needToShowConfirmDialog = false;
   }

   public boolean needToShowConfirmDialog() {
      return this.needToShowConfirmDialog;
   }

   public void setNeedToShowConfirmDialog(boolean needToShowConfirmDialog) {
      this.needToShowConfirmDialog = needToShowConfirmDialog;
   }
}