编辑:
问题解决了,我没有在XML文件中写实体的确切位置,那里只有一个标签。
我正在尝试将这些类映射到数据库,但出现此错误:
Exception in thread "main" org.hibernate.MappingException: Association references unmapped class: Reservation
at org.hibernate.cfg.HbmBinder.bindCollectionSecondPass(HbmBinder.java:2557)
at org.hibernate.cfg.HbmBinder$CollectionSecondPass.secondPass(HbmBinder.java:2808)
at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:70)
at org.hibernate.cfg.Configuration.originalSecondPassCompile(Configuration.java:1695)
at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1424)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1844)
at entities.chairandtabletest.main(chairandtabletest.java:39)
我试图找到我的问题出在哪里,我读到了这个异常,但我不明白程序中的问题出在哪里。
课程:
public class Customer {
private Integer id;
private String fullName;
private String address;
private String email;
private String phoneNumber;
private List<Reservation> reservations = new ArrayList<Reservation>();
}
public class Reservation{
private Integer id;
private String date;
private Integer totalSum;
private boolean isDeliever;
private List<Item> items = new ArrayList<Item>();
}
public class Item {
private Integer id;
private String name;
private Integer price;
}
表格:
CREATE TABLE ITEM(
item_id INT NOT NULL AUTO_INCREMENT,
item_name VARCHAR(40),
item_price INT NOT NULL,
reservation_id INT,
PRIMARY KEY(item_id)
);
CREATE TABLE RESERVATION(
reservation_id INT NOT NULL AUTO_INCREMENT,
reservarion_date VARCHAR(255),
reservtion_delivery BOOL,
reservation_total_sum INT,
customer_id INT,
PRIMARY KEY(reservation_id)
);
CREATE TABLE CUSTOMERS(
customer_id INT NOT NULL AUTO_INCREMENT,
customer_full_name VARCHAR(40),
customer_address VARCHAR(255),
customer_email VARCHAR(255),
customer_phone_number VARCHAR(20),
PRIMARY KEY(customer_id)
);
XML文件:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://127.0.0.1:3306/chairandtable?serverTimezone=UTC</property>
<property name="hibernate.connection.username">aliali</property>
<property name="hibernate.connection.password">password</property>
<mapping resource="props/customer.hbm.xml"/>
<mapping resource="props/reservation.hbm.xml"/>
<mapping resource="props/item.hbm.xml"/>
</session-factory>
</hibernate-configuration>
<?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="entities.Customer" table="customers">
<meta attribute="class-description">
This class contain customers details.
</meta>
<id name="id" type="integer" column="customer_id">
<generator class="identity"/>
</id>
<bag name="reservations" cascade="all">
<key column= "customer_id"/>
<one-to-many class="Reservation"/>
</bag>
<property name="fullName" column="customer_full_name" type="string"/>
<property name="address" column="customer_adress" type="string"/>
<property name="email" column="customer_email" type="string"/>
<property name="phoneNumber" column="customer_phone_number" type="string"/>
</class>
</hibernate-mapping>
<?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 ="entities.Reservation" table="reservation">
<meta attribute="class-description">
This class contain reservation detail.
</meta>
<id name ="id" column="reservation_id" type="integer">
<generator class="identity"/>
</id>
<bag name="items" cascade="all">
<key column="reservation_id"/>
<one-to-many class="Item"/>
</bag>
<property name="date" column="reservation_date" type="string"/>
<property name="totalSum" column="reservation_total_sum" type="integer"/>
<property name="isDeliver" column="reservtion_delivery" type="boolean"/>
</class>
</hibernate-mapping>
<?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="entities.Item" table="item">
<id name= "id" column="item_id" type="integer">
<generator class="identity"/>
</id>
<property name="name" column="item_name" type="string"/>
<property name="price" column="item_price" type="integer"/>
</class>
</hibernate-mapping>
我认为问题是我声明的表,也许与表不匹配 xml文件。
答案 0 :(得分:0)
您需要将* hbm.xml配置的顺序更改为:
<mapping resource="props/item.hbm.xml"/>
<mapping resource="props/reservation.hbm.xml"/>
<mapping resource="props/customer.hbm.xml"/>
将“实体”包添加到您的所有一对多映射中,如下所示:
<one-to-many class="entities.Item"/>