Hibernate 复合主键的映射问题

--角色权限关系表
create table role_power_relation(
	roleid int not null,
	powerid int not null,
	primary key(roleid,powerid)
	);

  此表有复合主键，Hibernate反向工程映射结果

<hibernate-mapping>
    <class name="com.qdhh.system.entity.RolePowerRelation" table="role_power_relation" catalog="curtain">
        <composite-id name="id" class="com.qdhh.system.entity.RolePowerRelation">
            <key-property name="roleid" type="integer">
                <column name="roleid" />
            </key-property>
            <key-property name="powerid" type="integer">
                <column name="powerid" />
            </key-property>
        </composite-id>
    </class>
</hibernate-mapping>

 

 

java 文件

 

public class RolePowerRelation implements Serializable{

	// Fields
	private Integer roleid;
	private Integer powerid;

	// Constructors

	/** default constructor */
	public RolePowerRelation() {
	}

	/** full constructor */
	public RolePowerRelation(Integer roleid, Integer powerid) {
		this.roleid = roleid;
		this.powerid = powerid;
	}
……省略get和set方法

 

junit测试代码

 

public class TestCurtainDAO extends TestCase{

	String[] xmls=new String[]{
							"D:\\Apache Software Foundation\\Tomcat 6.0\\webapps\\Curtain\\WEB-INF\\applicationContext.xml",
							"D:\\Apache Software Foundation\\Tomcat 6.0\\webapps\\Curtain\\WEB-INF\\applicationContext-action.xml",
							"D:\\Apache Software Foundation\\Tomcat 6.0\\webapps\\Curtain\\WEB-INF\\applicationContext-dao.xml"};
	
	BeanFactory factory=new FileSystemXmlApplicationContext(xmls);

	private CurtainHibernateDAO service;
	@Override
	protected void setUp() throws Exception {
		// TODO Auto-generated method stub
		super.setUp();
	}

	@Override
	protected void tearDown() throws Exception {
		// TODO Auto-generated method stub
		super.tearDown();
	}
	
	public void testFindAll()
	{
		service=(CurtainHibernateDAO)factory.getBean("curtainDAO");
		List<Curtain> curtains=service.findAll();
		for (Curtain curtain : curtains) {
			System.out.println(curtain.getTime()+"\t"+curtain.getSummary()+"\t"+curtain.getPropertyid()+"\t"+curtain.getBorrow()+"\t"+curtain.getLoan()+"\t"+curtain.getBalance());
		}
	}
	
}

此测试只是启动spring，只要启动spring就会报错的

 

测试结果

 

Caused by: org.hibernate.PropertyNotFoundException: Could not find a getter for id in class com.qdhh.system.entity.RolePowerRelation
	at org.hibernate.property.BasicPropertyAccessor.createGetter(BasicPropertyAccessor.java:282)
	at org.hibernate.property.BasicPropertyAccessor.getGetter(BasicPropertyAccessor.java:275)
	at org.hibernate.tuple.PropertyFactory.getGetter(PropertyFactory.java:168)
	at org.hibernate.tuple.PropertyFactory.buildIdentifierProperty(PropertyFactory.java:44)
	at org.hibernate.tuple.entity.EntityMetamodel.<init>(EntityMetamodel.java:123)
	at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:434)
	at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:109)
	at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:55)
	at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:226)
	at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1294)
	at org.springframework.orm.hibernate3.LocalSessionFactoryBean.newSessionFactory(LocalSessionFactoryBean.java:814)
	at org.springframework.orm.hibernate3.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:732)
	at org.springframework.orm.hibernate3.AbstractSessionFactoryBean.afterPropertiesSet(AbstractSessionFactoryBean.java:211)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1367)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1333)
	... 41 more
)
	

 

说明：

  Hibernate映射联合主键表的时候，会将联合主键抽取成一个类，查询记录是就按照联合主键方式方式来查找了。
    当然，我们也可也不让他抽取，如果没必要的话。

 

解决办法：

 
方法1.将hbm文件的   <composite-id name="id" class="com.qdhh.system.entity.RolePowerRelation">
改成 <composite-id >

方法2.创建一个复合主键的类

public class Key implements Serializable {   
    private int roleid;   
    private String powerid;   
       // 省略所有getter和setter方法   
} 

 

    修改hbm文件

<composite-id name="id" class="Key">