使用JSP和Servlet顯示當前日期

Question

我正在嘗試做有關Web編程（JSP和Servlet）的作業，但看不到代碼中的錯誤。

我的index.jsp是：

    <%@ 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>Data (sem JavaBeans)</title>
</head>
<body>

<a href="Data">Atualizar data</a>
<br/>

<%

    if (request.getAttribute("dia") != null)
    {
        int dia = (Integer) request.getAttribute("dia");
        int mes = (Integer) request.getAttribute("mes");
        int ano = (Integer) request.getAttribute("ano");
        int hora = (Integer) request.getAttribute("hora");
        int minuto = (Integer) request.getAttribute("minuto");

        String sDia = String.format("%2d",Integer.toString(dia));
        String sMes = String.format("%2d",Integer.toString(mes));
        String sAno = String.format("%4d",Integer.toString(ano));
        String sHora = String.format("%2d",Integer.toString(hora));
        String sMinuto = String.format("%2d",Integer.toString(minuto));

        out.print("A hora atual é: " + sDia + "/" + sMes + "/" + sAno + " - " + sHora + ":" + sMinuto);
    }
%>
</body>
</html>

而我的servlet是：

package br.com.gabriel;

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class Data
 */
@WebServlet("/Data")
public class Data extends HttpServlet {
    private static final long serialVersionUID = 1L;

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

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    @SuppressWarnings("deprecation")
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        Date d = new Date();

        int dia = d.getDate();
        int mes = d.getMonth() + 1;
        int ano = d.getYear() + 1900;
        int hora = d.getHours();
        int minuto = d.getMinutes();

        request.setAttribute("dia", dia);
        request.setAttribute("mes", mes);
        request.setAttribute("ano", ano);
        request.setAttribute("hora", hora);
        request.setAttribute("minuto", minuto);

        request.getRequestDispatcher("index.jsp").forward(request, response);
    };
}

我得到的錯誤是：

java.util.IllegalFormatConversionException: d != java.lang.String

但是我看不出這里哪里錯了...

提前致謝！ 加布里埃爾

Answer 1

在像

String sDia = String.format("%2d",Integer.toString(dia));

擺脫Integer.toString(..)調用。 d模式用於

%2d

期望一個整數值，但是您將其傳遞給String 。

簡單地做

String sDia = String.format("%2d", dia);

使用JSP和Servlet顯示當前日期

問題描述

1 個解決方案

解決方案1
1 已采納 2014-04-06 22:33:25

使用JSP和Servlet顯示當前日期

問題描述

1 個解決方案

解決方案1 1 已采納 2014-04-06 22:33:25

解決方案1
1 已采納 2014-04-06 22:33:25