JPA - 使用注释在模型 [英] JPA - using annotations in a model

问题描述

我的应用程序在JPA / Hibernate中，Spring和检票运行。我想我们的ORM从XML文件转换为JPA注解。带注释的模式是这样的：

My application runs on JPA/Hibernate, Spring and Wicket. I'm trying to convert our ORM from XML files to JPA annotations. The annotated model looks like this:

@Entity
@Table(name = "APP_USER")
public class User extends BaseObject {
    private Long id;
    private String firstName;
    private String lastName;
    private String email;

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    @Column(name = "ID")
    public Long getId() {
        return id;
    }

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

    @Column(name="FIRST_NAME")
    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    @Column(name="LAST_NAME")
    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    @Column(name="EMAIL")
    public String getEmail() {
        return email;
    }

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

    /**
     * @return Returns firstName and lastName
     */
    public String getFullName() {
        return firstName + ' ' + lastName;
    }
}

原来，虽然，它是没有标注，并在User.hbm.xml被描述的映射：

Originally, though, it was without annotation and the mapping was described in User.hbm.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
    <class name="org.appfuse.model.User" table="app_user">
        <id name="id" column="id" unsaved-value="null">
            <generator class="increment"/>
        </id>
        <property name="firstName" column="first_name" not-null="true"/>
        <property name="lastName" column="last_name" not-null="true"/>
        <property name="email" column="email"/>
    </class>
</hibernate-mapping>

当我删除映射文件，并尝试使用刚刚注释中，EntityManagerFactory还没有生成，唯独

When I delete the mapping file and try to use just the annotations, the entityManagerFactory doesn't get created, with the exception

org.hibernate.PropertyNotFoundException：
  找不到属性的设置
  全名类
  org.appfuse.model.User。

有没有映射设置此属性，因为它只是一个方便的方法。我该怎么办错了？

There's no mapping set for this property, because it's just a convenience method. What do I do wrong?

推荐答案

标记方法，<一个href=\"http://download.oracle.com/javaee/5/api/javax/persistence/Transient.html\"><$c$c>@Transient所以Hibernate会忽略它：

Mark the method as @Transient so Hibernate will ignore it:

/**
 * @return Returns firstName and lastName
 */
@Transient
public String getFullName() {
    return firstName + ' ' + lastName;
}

在默认情况下，一切都看起来像一个getter映射。

By default, everything that looks like a getter is mapped.

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