Java 游戏框架2埃宾:为什么';无法获取相关对象?
这是我的Java 游戏框架2埃宾:为什么';无法获取相关对象?,java,playframework-2.0,ebean,Java,Playframework 2.0,Ebean,这是我的用户: package models.user; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.Id; import javax.persistence.ManyToOne; import javax.persistence.Table; import play.data.val
用户
:
package models.user;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import play.data.validation.Constraints.MaxLength;
import play.data.validation.Constraints.MinLength;
import play.data.validation.Constraints.Required;
import play.db.ebean.Model;
@Entity
@Table(name = "T_USER")
public class User extends Model {
@Id
public Long id;
@Required
@MaxLength(30)
@MinLength(4)
public String username;
@Required
@MaxLength(30)
@MinLength(4)
public String password;
@ManyToOne(fetch = FetchType.EAGER)
@Column(nullable = false)
public Role role;
public static Finder<Long, User> find = new Finder<Long, User>(Long.class, User.class);
public User() {
}
public User(String username, String password, Role role) {
this.username = username;
this.password = password;
this.role = role;
}
@Override
public String toString() {
return "[Tying to login : ] [" + username + " - " + password + "]";
}
}
问题是,
user.role.name
为空,但是user.role.id
在这里是正确的,为什么EBean不帮助我为用户获取role
?我在不同的场合遇到过这个问题。您可以执行以下操作:
首先,尝试用私有字段替换公共字段,并添加适当的getter和setter(无论如何,在使用Java时,这是一个很好的模式)
其次,您可以编写一个查找/获取所需信息的小助手。假设您需要通过Id获取用户,并执行此字符串检查。然后在User
类中,您可以编写如下方法:
public static User findById(Long id) {
return Ebean.find(User.class)
.fetch("role")
.where()
.eq("id", id)
.findUnique();
}
之后,只需使用以下方法:
public static Result modules(Long id) {
User user = User.findById(id);
if ("Super User".equalsIgnoreCase(user.getRole().getName())) {
return ok();
} else {
return forbidden();
}
}
public static Result modules(Long id) {
User user = User.findById(id);
if ("Super User".equalsIgnoreCase(user.getRole().getName())) {
return ok();
} else {
return forbidden();
}
}