我的 spring MVC 控制器不断收到 org.springframework.web.util.NestedServletException：请求处理失败；嵌套异常是 java.lang.NullPointerException
我的代码如下：
电影.jsp
<%@taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<c:choose>
<c:when test="true">
<h2>Please enter the details below:</h2>
<form:form method="POST" commandName="movie">
<table>
<tr><td>Lead Actor:</td><td><form:input path="actor"/></td></tr>
<tr><td>Lead Actress:</td><td><form:input path="actoress"/></td></tr>
<tr><td>Genre:</td><td><form:input path="genre"/></td></tr>
<tr><td>Year:</td><td><form:input path="year"/></td></tr>
</table>
<form:hidden path="way" value="add"/>
<form:hidden path="page" value="5"/>
<input type="submit" value="Add Moives"/>
</form:form>
</c:when>
<c:when test="${requestScope.page eq '2'}">
<h2>Searching Movies</h2>
<form:form method="POST" commandName="movie">
Keyword:<form:input path="key"/><br/>
<form:radiobutton path="search" value="title"/>Search By Title<br/>
<form:radiobutton path="search" value="actor"/>Search By Actor<br/>
<form:radiobutton path="search" value="actress"/>Search By Actress<br/>
<form:hidden path="way" value="browse"/>
<form:hidden path="page" value="5"/>
<input type="submit" value="Search Moives"/>
</form:form>
</c:when>
<%-- <c:when test="${requestScope.page eq '3'}">
<p>Add movie successful</p>
</c:when>
<c:when test="${requestScope.page eq '3'}">
<p>Movie Title:${requestScope.title}</p>
<p>Actor:${requestScope.actor}</p>
<p>Actress:${requestScope.actress}</p>
<p>Genre:${requestScope.Genre}</p>
<p>Year:${requestScope.Year}</p>
</c:when> --%>
<c:otherwise>
<h2>Welcome to our Movie Store</h2>
<p>Please make your selection below</p>
<!--<form method="post" action="movie.htm">
<select name="page">
<option value="2">Browse Movies</option>
<option value="1">Add New Movie to Database</option>
</select>
<input type="submit" value="Send"/>
</form> -->
<form:form method="POST" action="movie.htm" commandName="movie">
<form:select path="page">
<form:option value="1">Add New Movie to Database</form:option>
<form:option value="2">Browse Movies</form:option>
</form:select>
<input type="submit" value="Send"/>
</form:form>
</c:otherwise>
</c:choose>
</body>
</html>
这是我的控制器：
public class movieController extends SimpleFormController {
public movieController() {
//Initialize controller properties here or
//in the Web Application Context
setCommandClass(Movie.class);
setCommandName("movie");
setSuccessView("movie");
setFormView("movie");
}
/*
@Override
protected void doSubmitAction(Object command) throws Exception {
throw new UnsupportedOperationException("Not yet implemented");
}
* */
//Use onSubmit instead of doSubmitAction
//when you need access to the Request, Response, or BindException objects
@Override
protected ModelAndView onSubmit(
HttpServletRequest request,
HttpServletResponse response,
Object command,
BindException errors) throws Exception {
//Do something...
Movie movie = new Movie();
String page = movie.getPage();
if(page.equals("1")||page.equals("2")){
request.setAttribute("page",'1');
}
else{
Connection con = null;
Statement statement = null;
ResultSet st = null;
if(movie.getWay().equals("add")){
String title = movie.getTitle();
title = title.replaceAll("[^A-Za-z0-9\\s]","");
String actor = movie.getActor();
actor = actor.replaceAll("[^A-Za-z0-9\\s]","");
String actress = movie.getActoress();
actress = actress.replaceAll("[^A-Za-z0-9\\s]","");
String genre = movie.getGenre();
genre = genre.replaceAll("[^A-Za-z0-9\\s]","");
String year_temp = movie.getYear();
year_temp = year_temp.replaceAll("[^A-Za-z0-9\\s]","");
int year = Integer.parseInt(year_temp);
try{
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/moviedb",
"root","");
String sql = "INSERT INTO movies (title,actor,actress,genre,year) VALUES
('"+title+"','"+actor+"','"+actress+"','"+genre+"','"+year+"')";
statement = con.createStatement();
statement.executeUpdate(sql);
} catch (SQLException ex) {
// TODO Auto-generated catch block
System.out.println("error happend:" + ex);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
System.out.println("error happend:" + e);
}
finally{
try{
if(statement != null) statement.close();
if(con != null) con.close();
//request.setAttribute("page", "3");
} catch (SQLException ex) {
System.out.println("error happend:" + ex);
}
}
}
else{
String search = movie.getSearch();
String key = movie.getKey();
key = key.replaceAll("[^A-Za-z0-9\\s]","");
try{
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/moviedb", "root","");
String sql = "select * from movies where "+search+"='"+key+"'";
statement = con.createStatement();
st = statement.executeQuery(sql);
while (st.next()) {
request.setAttribute("page", "4");
request.setAttribute("title",st.getString(1));
request.setAttribute("actor",st.getString(2));
request.setAttribute("actress",st.getString(3));
request.setAttribute("Genre",st.getString(4));
request.setAttribute("Year",st.getInt(5));
}
} catch (SQLException ex) {
// TODO Auto-generated catch block
System.out.println("error happend:" + ex);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
System.out.println("error happend:" + e);
}
finally{
try{
if(st != null) st.close();
if(statement != null) statement.close();
if(con != null) con.close();
} catch (SQLException ex) {
System.out.println("error happend:" + ex);
}
}
}
//End
}
return new ModelAndView("movie","movie",movie);
}
}
非常感谢！