两个类:
<class name="SpreadsheetImportTemplate" table="spreadsheetimport_template">
<id name="id" type="int" column="id" unsaved-value="0">
<generator class="native" />
</id>
<property name="name" type="java.lang.String" column="name" not-null="true" length="100" />
<many-to-one name="creator" class="org.openmrs.User" not-null="true" />
<property name="created" type="java.util.Date" column="date_created" not-null="true"
length="19" />
<many-to-one name="modifiedBy" column="changed_by" class="org.openmrs.User" not-null="false" />
<property name="modified" type="java.util.Date" column="date_changed" not-null="false" length="19" />
<!-- Associations -->
<!-- bi-directional one-to-many association to SpreadsheetImportTemplateColumn -->
<bag name="columns" cascade="all-delete-orphan" inverse="true">
<key column="template_id" not-null="true" />
<one-to-many class="SpreadsheetImportTemplateColumn" />
</bag>
</class>
<class name="SpreadsheetImportTemplateColumn" table="spreadsheetimport_template_column">
<id name="id" type="int" column="id" unsaved-value="0">
<generator class="native" />
</id>
<many-to-one name="template" class="SpreadsheetImportTemplate" column="template_id" />
<property name="columnName" type="java.lang.String" column="column_name" length="100" not-null="true" />
<property name="dbTableDotColumn" type="java.lang.String" column="db_table_dot_column" length="100" not-null="true"/>
<property name="extraData" type="java.lang.String" column="extra_data" length="100" not-null="false"/>
</class>
在java中,两者都有各自的getter和setter:
public class SpreadsheetImportTemplate {
Integer id;
String name;
Collection<SpreadsheetImportTemplateColumn> columns = new ArrayList<SpreadsheetImportTemplateColumn>();
Date created;
Date modified;
User creator;
User modifiedBy;
public SpreadsheetImportTemplate() {
}
...
public class SpreadsheetImportTemplateColumn {
Integer id;
SpreadsheetImportTemplate template;
String columnName;
String dbTableDotColumn;
String extraData;
public SpreadsheetImportTemplateColumn() {
}
...
但是,如果我们有一个包含某些列的 SpreadsheetImportTemplate
模板,并且执行 template.remove(0)
,然后执行 Hibernate saveOrUpdate
,则相关的 SpreadsheetImportTemplateColumn
不会从数据库中删除:(
感谢任何帮助。
仅供引用,这是创建数据库的相关 SQL:
CREATE TABLE IF NOT EXISTS `spreadsheetimport_template` (
`id` int(32) NOT NULL auto_increment,
`name` varchar(100) NOT NULL,
`creator` int(11) NOT NULL default '0',
`date_created` datetime NOT NULL default '0000-00-00 00:00:00',
`changed_by` int(11) default NULL,
`date_changed` datetime default NULL,
PRIMARY KEY (`id`),
KEY `User who wrote this spreadsheet template` (`creator`),
KEY `User who changed this spreadsheet template` (`changed_by`),
CONSTRAINT `User who wrote this spreadsheet template` FOREIGN KEY (`creator`) REFERENCES `users` (`user_id`),
CONSTRAINT `User who changed this spreadsheet template` FOREIGN KEY (`changed_by`) REFERENCES `users` (`user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE IF NOT EXISTS `spreadsheetimport_template_column` (
`id` int(32) NOT NULL auto_increment,
`template_id` int(32) NOT NULL default '0',
`column_name` varchar(100) NOT NULL,
`db_table_dot_column` varchar(100) NOT NULL,
`extra_data` varchar(100),
PRIMARY KEY (`id`),
KEY `Spreadsheet template to which this column belongs` (`template_id`),
CONSTRAINT `Spreadsheet template to which this column belongs` FOREIGN KEY (`template_id`) REFERENCES `spreadsheetimport_template` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
最佳答案
只是相关部分
电子表格导入模板
public class SpreadsheetImportTemplate {
private Integer id;
public Integer getId() { return id; }
public void setId(Integer id) { this.id = id; }
private Collection<SpreadsheetImportTemplateColumn> columns = new ArrayList<SpreadsheetImportTemplateColumn>();
public Collection<SpreadsheetImportTemplateColumn> getColumns() { return columns; }
public void setColumns(Collection<SpreadsheetImportTemplateColumn> columns) { this.columns = columns; }
/**
* set up both sides
*/
public void addColumn(SpreadsheetImportTemplateColumn column) {
getColumns().add(column);
column.setTemplate(this);
}
}
电子表格导入模板列
public class SpreadsheetImportTemplateColumn {
private Integer id;
public Integer getId() { return id; }
public void setId(Integer id) { this.id = id; }
private SpreadsheetImportTemplate template;
public SpreadsheetImportTemplate getTemplate() { return template; }
public void setTemplate(SpreadsheetImportTemplate template) { this.template = template; }
}
映射
<?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 package="br.com._3589013.model.domain">
<class name="SpreadsheetImportTemplate">
<id name="id">
<generator class="native"/>
</id>
<bag name="columns" cascade="all,delete-orphan" inverse="true">
<key/>
<one-to-many class="SpreadsheetImportTemplateColumn"/>
</bag>
</class>
<class name="SpreadsheetImportTemplateColumn">
<id name="id">
<generator class="native"/>
</id>
<many-to-one name="template" class="SpreadsheetImportTemplate"/>
</class>
</hibernate-mapping>
测试
public class PersistenceTest {
private static SessionFactory sessionFactory;
private Serializable id;
@BeforeClass
public static void setUpClass() {
Configuration c = new Configuration();
c.addResource("mapping.hbm.3589013.xml");
sessionFactory = c.configure().buildSessionFactory();
}
@Before
public void setUp() throws Exception {
SpreadsheetImportTemplate sit = new SpreadsheetImportTemplate();
sit.addColumn(new SpreadsheetImportTemplateColumn());
Session session = sessionFactory.openSession();
session.beginTransaction();
id = session.save(sit);
session.getTransaction().commit();
}
@Test
public void removedOrphan() throws Exception {
Session session = sessionFactory.openSession();
session.beginTransaction();
List<SpreadsheetImportTemplateColumn> sitcList = session.createQuery("from SpreadsheetImportTemplateColumn").list();
assertTrue(sitcList.size() == 1);
SpreadsheetImportTemplate sit = (SpreadsheetImportTemplate) session.get(SpreadsheetImportTemplate.class, id);
sit.getColumns().remove(sitcList.get(0));
session.getTransaction().commit();
assertTrue(sit.getColumns().size() == 0);
}
}
效果很好!
关于java - Hibernate 反向一对多映射似乎无法正确处理从 Java 列表中删除项目,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/3589013/