您好，我的 jsp 页面返回空属性。每次填写表格时，我都会收到“必须填写所有字段”错误。这是我的代码：
jsp代码
<%@ page pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Registration with eBank</title>
<link type="text/css" rel="stylesheet" href="style1.css" />
</head>
<body>
<form method="post" action="registrationAdmin" enctype="multipart/form-data">
<fieldset>
<legend>Personal Information</legend>
<p>Begin your application with this form.</p>
<label for="firstname">First name <span class="required">*</span></label>
<input type="text" id="firstname" name="firstname"
value="<c:out value="${admin.firstname}"/>" size="20" maxlength="60" />
<span class="error">${form.errors['firstname']}</span> <br />
<label for="lastname">Last name <span class="required">*</span></label> <input
type="text" id="lastname" name="lastname"
value="<c:out value="${admin.lastname}"/>" size="20" maxlength="60" />
<span class="error">${form.errors['lastname']}</span> <br />
<label for="email">Email address <span class="required">*</span></label>
<input type="email" id="email" name="email"
value="<c:out value="${admin.email}"/>" size="20" maxlength="60" />
<span class="error">${form.errors['email']}</span> <br />
<label for="password">Password <span class="required">*</span></label>
<input type="password" id="password" name="password" value=""
size="20" maxlength="20" /> <span class="error">${form.errors['password']}</span>
<br />
<label for="confirmation">Confirmation of password <span class="required">*</span></label>
<input type="password" id="confirmation" name="confirmation" value="" size="20" maxlength="20" />
<span class="error">${form.errors['confirmation']}</span>
<br />
<br />
<input type="submit" value="registration" class="sansLabel" />
<br />
<p class="${empty form.errors ? 'success' : 'error'}">${form.result}</p>
<br />
</fieldset>
</form>
</body>
</html>
小服务程序代码：
public class RegistrationAdmin extends HttpServlet {
public static final String CONF_DAO_FACTORY = "daofactory";
public static final String ATT_ADMIN = "admin";
public static final String ATT_FORM = "form";
public static final String VUE = "/WEB-INF/registrationAdmin.jsp";
private AdminDao adminDao;
public void init() throws ServletException{
//get instance of DAO user
this.adminDao = ((DAOFactory)getServletContext().getAttribute(CONF_DAO_FACTORY)).getAdminDao();
}
public void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException{
/* Affichage de la page d'inscription */
this.getServletContext().getRequestDispatcher( VUE ).forward( request, response );
}
public void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException{
//String path = this.getServletConfig().getInitParameter(PATH);
/* Préparation de l'objet formulaire */
RegistrationAdminForm form = new RegistrationAdminForm(adminDao);
/* Appel au traitement et à la validation de la requête, et récupération du bean en résultant */
Admin admin = form.registerAdmin( request);
/* Stockage du formulaire et du bean dans l'objet request */
request.setAttribute( ATT_FORM, form );
request.setAttribute( ATT_ADMIN, admin);
this.getServletContext().getRequestDispatcher( VUE ).forward( request, response );
}
}
和我的表单代码：
public class RegistrationAdminForm {
private static final String EMAIL_FIELD = "email";
private static final String PASS_FIELD = "password";
private static final String FNAME_FIELD = "firstname";
private static final String LNAME_FIELD = "lastname";
private static final String CONF_FIELD = "confirmation";
private static final String ALGO = "SHA-256";
private String result;
private Map<String, String> errors = new HashMap<String, String>();
public String getResult() {
return result;
}
public Map<String, String> getErrors() {
return errors;
}
private AdminDao adminDao;
public RegistrationAdminForm(AdminDao adminDao){
this.adminDao = adminDao;
}
public Admin registerAdmin( HttpServletRequest request ) {
String email = getFieldValue( request, EMAIL_FIELD );
String password = getFieldValue( request, PASS_FIELD );
String firstname = getFieldValue( request, FNAME_FIELD );
String lastname = getFieldValue( request, LNAME_FIELD );
String confimation = getFieldValue( request, CONF_FIELD );
Admin admin = new Admin();
try{
try {
validateEmail( email );
} catch (FormValidationException e ) {
setError( EMAIL_FIELD, e.getMessage() );
}
admin.setEmail( email );
try {
validateName( firstname, lastname );
} catch (FormValidationException e ) {
setError( FNAME_FIELD, e.getMessage() );
setError( LNAME_FIELD, e.getMessage() );
}
admin.setFirstname(firstname);
admin.setLastname(lastname);
treatPassword(password, confimation, admin);
if ( errors.isEmpty() ) {
adminDao.create(admin);
result = "Congrats, you are successfully registred!";
} else {
result = "Registration failed. Please try again!";
}
}catch(DAOException e){
result = "Registration Error, Please try again Later...";
e.printStackTrace();
}
return admin;
}
private void validateName( String firstname, String lastname ) throws FormValidationException {
if ( firstname != null && lastname !=null ) {
if ( firstname.length() < 3 ) {
throw new FormValidationException( "Firstname must be at least 3 characters long" );
}else if ( lastname.length() < 3 ){
throw new FormValidationException( "Lastname must be at least 3 characters long" );
}
} else {
throw new FormValidationException( "All fields must be filled out." );
}
}
private void validateEmail( String email ) throws FormValidationException {
if ( email != null ) {
if ( !email.matches( "([^.@]+)(\\.[^.@]+)*@([^.@]+\\.)+([^.@]+)" ) ) {
throw new FormValidationException( "Please enter a valid email address!" );
}else if(adminDao.find(email)!= null){
throw new FormValidationException("This email address is already used for another account, Please choose another email address.");
}
}else{
throw new FormValidationException( "Please enter an email address!" );
}
}
private void treatPassword (String password, String confirmation, Admin admin){
try {
validatePassword( password, confirmation );
} catch ( FormValidationException e ) {
setError( PASS_FIELD, e.getMessage() );
setError( CONF_FIELD, null );
}
ConfigurablePasswordEncryptor passwordEncryptor = new ConfigurablePasswordEncryptor();
passwordEncryptor.setAlgorithm( ALGO );
passwordEncryptor.setPlainDigest( false );
String encyptedPassword = passwordEncryptor.encryptPassword( password );
admin.setPassword(encyptedPassword);
}
private void validatePassword( String password, String confirmation ) throws FormValidationException {
if ( password != null && confirmation != null ) {
if ( !password.equals( confirmation ) ) {
throw new FormValidationException( "Passwords don't match!" );
} else if ( password.length() < 6 ) {
throw new FormValidationException( "Passwords must be at least 6 characters long" );
}
} else {
throw new FormValidationException( "Please enter and confirm your password!" );
}
}
private void setError( String field, String message ) {
errors.put( field, message );
}
private static String getFieldValue( HttpServletRequest request, String FieldName ) {
String value = request.getParameter( FieldName );
if ( value == null || value.trim().length() == 0 ) {
return null;
} else {
return value;
}
}
}
尽管参数名称与 JSP 中的名称匹配，但 request.getParamaeter("param") 每次都返回 null。任何帮助将不胜感激。谢谢