Pessoal, boa noite.
Pesquisei no fórum acerca do problema que estou enfrentando, porém não obtive sucesso quanto a resolução do mesmo.
De acordo com a apostila da Caelum java-web-fj21, estou tentando fazer o exercício 11.14.
Ao tentar acessar a listagem das tarefas cadastradas, a mesma apresenta erro.
De acordo com o Log, estou com o seguinte erro:
127.0.0.1 - - [06/Jun/2014:23:43:54 -0300] “GET /fj21-tarefas/listaTarefas HTTP/1.1” 500 3680
Segue também a página de erro apresentada:
HTTP Status 500 - Request processing failed; nested exception is java.lang.NullPointerException
type Exception report
message Request processing failed; nested exception is java.lang.NullPointerException
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:965)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:844)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
root cause
java.lang.NullPointerException
java.util.Calendar.setTime(Calendar.java:1076)
br.com.caelum.tarefas.dao.JdbcTarefaDao.lista(JdbcTarefaDao.java:56)
br.com.caelum.tarefas.controller.TarefasController.lista(TarefasController.java:38)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:685)
org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:919)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:851)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:844)
javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.53 logs.
Apache Tomcat/7.0.53
Seguem também meus arquivos para implementação desta funcionalidade.
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
id="WebApp_ID" version="2.5">
<display-name>fj21-tarefas</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>
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
TarefasController.java
package br.com.caelum.tarefas.controller;
import java.util.List;
import javax.validation.Valid;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import br.com.caelum.tarefas.dao.JdbcTarefaDao;
import br.com.caelum.tarefas.modelo.Tarefa;
@Controller
public class TarefasController
{
@RequestMapping("novaTarefa")
public String form(){
return "tarefa/formulario";
}
@RequestMapping("adicionaTarefa")
public String adiciona(@Valid Tarefa tarefa, BindingResult result)
{
if(result.hasFieldErrors("descricao")){
return "tarefa/formulario";
}
JdbcTarefaDao dao = new JdbcTarefaDao();
dao.adiciona(tarefa);
return "tarefa/adicionada";
}
@RequestMapping("listaTarefas")
public String lista(Model model)
{
JdbcTarefaDao dao = new JdbcTarefaDao();
model.addAttribute("tarefas", dao.lista());
return "tarefa/lista";
}
}
JdbcTarefaDao.java
package br.com.caelum.tarefas.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import br.com.caelum.tarefas.jdbc.ConnectionFactory;
import br.com.caelum.tarefas.modelo.Tarefa;
public class JdbcTarefaDao {
private Connection connection;
public JdbcTarefaDao()
{
this.connection = new ConnectionFactory().getConnection();
}
public void adiciona(Tarefa tarefa)
{
String sql = "Insert into tarefas (descricao, finalizado) values(?, ?)";
try
{
PreparedStatement stmt = connection.prepareStatement(sql);
stmt.setString(1, tarefa.getDescricao());
stmt.setBoolean(2, tarefa.isFinalizado());
// stmt.setDate(3, new Date(tarefa.getDataFinalizacao().getTimeInMillis()) );
stmt.execute();
stmt.close();
}catch(SQLException e)
{
throw new RuntimeException(e);
}
}
public List<Tarefa> lista()
{
try{
List<Tarefa> tarefas = new ArrayList<Tarefa>();
PreparedStatement stmt = this.connection.prepareStatement("select * from tarefas");
ResultSet rs = stmt.executeQuery();
while (rs.next())
{
Tarefa tarefa = new Tarefa();
tarefa.setId(rs.getLong("id"));
tarefa.setDescricao(rs.getString("descricao"));
tarefa.setFinalizado(rs.getBoolean("finalizado"));
Calendar data = Calendar.getInstance();
data.setTime(rs.getDate("dataFinalizacao"));
tarefa.setDataFinalizacao(data);
tarefas.add(tarefa);
}
rs.close();
stmt.close();
return tarefas;
}
catch (SQLException e)
{
throw new RuntimeException(e);
}
}
}
lista.jsp
<%@ 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">
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<a href="novaTarefa">Criar nova tarefa</a>
<br /><br />
<table>
<tr>
<th>Id</th>
<th>Descrição</th>
<th>Finalizado?</th>
<th>Data de finalização</th>
</tr>
<c:forEach items="${tarefas}" var="tarefa">
<tr>
<td>${tarefa.id}</td>
<td>${tarefa.descricao}</td>
<c:if test="${tarefa.finalizado eq false}">
<td>Não finalizado</td>
</c:if>
<c:if test="${tarefa.finalizado eq true}">
<td>Finalizado</td>
</c:if>
<td>
<fmt:formatDate
value="${tarefa.dataFinalizacao.time}"
pattern="dd/MM/yyyy"/>
</td>
</tr>
</c:forEach>
</table>
</body>
</html>
spring-context.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd">
<context:component-scan base-package="br.com.caelum.tarefas.controller" />
<mvc:annotation-driven />
<mvc:resources mapping="/resources/**" location="/resources/" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/views/"/>
<property name="suffix" value=".jsp"/>
</bean>
<bean id="messageSource" class= "org.springframework.context.support.ReloadableResourceBundleMessageSource">
<property name="basename" value="/WEB-INF/mensagens"></property>
</bean>
</beans>
Tarefa.java
package br.com.caelum.tarefas.modelo;
import java.util.Calendar;
import javax.validation.constraints.Size;
import com.sun.istack.internal.NotNull;
public class Tarefa
{
private Long id;
@NotNull//(message="{tarefa.descricao.vazia}")
@Size(min=5, message="{tarefa.descricao.pequena}")
private String descricao;
private boolean finalizado;
private Calendar dataFinalizacao;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getDescricao() {
return descricao;
}
public void setDescricao(String descricao) {
this.descricao = descricao;
}
public boolean isFinalizado() {
return finalizado;
}
public void setFinalizado(boolean finalizado) {
this.finalizado = finalizado;
}
public Calendar getDataFinalizacao() {
return dataFinalizacao;
}
public void setDataFinalizacao(Calendar dataFinalizacao) {
this.dataFinalizacao = dataFinalizacao;
}
}
Agradeço a ajuda de todos.
Abraço,
Fernando Nascimento