春季MVC視圖 - 解決佔位符

Question

我是初學者在春天mvc。這裏是我的控制器

@Controller 
public class UserController { 
@RequestMapping(value="/register", method = RequestMethod.GET) 
public ModelAndView registerUser(){ 
    User user = new User(); 
    user.setNickName("aaa"); 
    user.setId(1); 
    user.setEmail("aaa@gmail.com"); 
    ModelAndView model = new ModelAndView("register", "model", user); 
    return model; 
} 

我的User類

package org.proffart.bet.domain; 

import javax.persistence.Column; 
import javax.persistence.Entity; 
import javax.persistence.GeneratedValue; 
import javax.persistence.Id; 
import javax.persistence.Table; 

@Entity 
@Table(name="users") 
public class User { 
    @Id 
    @Column(name="id") 
    @GeneratedValue 
    private Integer id; 

    @Column(name="nic_name") 
    private String nickName; 

    @Column(name="email") 
    private String email; 

    @Column(name="password") 
    private String password; 

    @Column(name="balance") 
    private Double balance; 

    public String getEmail(){ 
     return email; 
    } 

    public void setEmail(String email){ 
     this.email = email; 
    } 

    public String getNickName(){ 
     return nickName; 
    } 

    public void setNickName(String nickName){ 
     this.nickName = nickName; 
    } 

    public String getPassword(){ 
     return password; 
    } 

    public void setPassword(String password){ 
     this.password = password; 
    } 

    public Double getBalance(){ 
     return balance; 
    } 

    public void setBalance(Double balance){ 
     this.balance = balance; 
    } 

    public Integer getId(){ 
     return id; 
    } 

    public void setId(int id){ 
     this.id = id; 
    } 
} 

我嘗試在我的JSP視圖（register.jsp），但無法顯示的東西。請向我解釋爲什麼你好${model.email}在jsp中不起作用。它向我顯示文本「Hello $ {model.email}」？

Answer 1

這裏有幾件事情可能會出錯，通常懷疑是web.xml中定義的容器合規性，舊的JSP 1.2必須具有該指示，並且您必須將其設置爲

<%@ page isELIgnored="false" %> 

如果你使用其中EL是默認啓用的新JSP版，您應該確保您的部署描述符（web.xml）至少complient到2.4版本

<web-app id="WebApp_ID" version="2.4" 
    xmlns="http://java.sun.com/xml/ns/j2ee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> 
//... 
</web-app> 

可以查找更多詳情here和here