hibernate報錯（一）

Exception in thread "main" org.hibernate.MappingException: could not instantiate id generator [entity-name=com.xss.domain.Employee]
at org.hibernate.id.IdentifierGeneratorFactory.create(IdentifierGeneratorFactory.java:132)
at org.hibernate.mapping.SimpleValue.createIdentifierGenerator(SimpleValue.java:175)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:224)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1327)
at com.xss.view.testMain.main(testMain.java:15)
Caused by: org.hibernate.MappingException: could not interpret id generator strategy: sequence 
at org.hibernate.id.IdentifierGeneratorFactory.getIdentifierGeneratorClass(IdentifierGeneratorFactory.java:151)
at org.hibernate.id.IdentifierGeneratorFactory.create(IdentifierGeneratorFactory.java:124)
... 4 more

<?xml version="1.0" encoding="UTF-8"?>
<!-- 該文件要清楚地表述出類和表的對應關係 -->
<!DOCTYPE hibernate-mapping PUBLIC
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
	<!-- package :表示該類在哪一個包下 -->
	<hibernate-mapping package="com.xss.domain">
	<!-- name:表示類名；table：表示該類和哪一個表映射 -->
		<class name="Employee" table="employee">
			<!-- id 元素專門用於指定主鍵是如何生成，hibernate設計者認爲，我們每一個表都應該擁有一個主鍵 -->
			<id name="id" column="id"  type="java.lang.Integer">
				<!-- 指定主鍵生成策略 -->
				<generator class="sequence ">
					<param name="sequence">EMP_SEQ</param>
				</generator>
			</id>
			<!-- 配置其他屬性 -->
			<property name="name" type="java.lang.String">
				<column name="name" not-null="false"/>
			</property>
			<property name="email" type="java.lang.String">
				<column name="email" not-null="false"/>
			</property>
			<property name="hiredate" type="java.util.Date">
				<column name="hiredate" not-null="false"/>
			</property>
		</class>
	</hibernate-mapping>

錯誤是因爲：

<id name="id" column="id"  type="java.lang.Integer">
				<!-- 指定主鍵生成策略 -->
				<generator class="sequence ">
					<param name="sequence">EMP_SEQ</param>
				</generator>
			</id>

class="sequence"多了一個空格

修改以後編譯，運行正常！！