最近做的兩個專案其中一個需求測試一下快取機制下的執行效率，結果配了半天，老是不起作用，而另一套同樣機制下的應用，確起作用查了兩個系統的配置也一樣，下面是我ehcache.xml 檔案的資訊

<?xml version="1.0" encoding="UTF-8"?>
<ehcache>
	<diskStore path="java.io.tmpdir" />
	<defaultCache maxElementsInMemory="999999999" eternal="true"
		timeToIdleSeconds="10000" timeToLiveSeconds="10000"
		overflowToDisk="true" />
</ehcache>

 下面是部份applicationContext.xml

<bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="dataSource" ref ="gzMobileSource" />
        <property name="lobHandler" ref ="oracleLobHandler" />
        <property name="mappingDirectoryLocations">
            <list>
                <value>classpath:/com/kmi/expert/model</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
                <prop key="hibernate.max_fetch_depth">0</prop>
                <prop key="hibernate.generate_statistics">true</prop>
                <prop key="hibernate.cache.use_query_cache">true</prop>
                <prop key="hibernate.cache.use_second_level_cache">true</prop>
                <prop key="cglib.use_reflection_optimizer">false</prop> 
                <prop key="hibernate.cache.provider_class">org.hibernate.cache.HashtableCacheProvider</prop>
                <prop key="hibernate.query.factory_class">org.hibernate.hql.ast.ASTQueryTranslatorFactory</prop>
            </props>
        </property>
    </bean>
 

ehcache.xml檔案放置在src目錄中，編譯後輸出在WEB-INF/classes/下面。持久類的對映如下

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >
<hibernate-mapping package="com.kmi.expert.model">
    <class name="Displaytype" table="DISPLAYTYPE">
        <cache usage="read-only"/>        
        <id name="id" type="integer" column="DISPLAYTYPEID">
            <generator class="org.hibernate.id.Assigned" />
        </id>
      中間部份略...
 </class>
</hibernate-mapping>

我對快取是否起作用的判斷是，通過執行相同的操作，檢查輸出的SQL，發現每次執行都輸出了相同的SQL，條數也一樣。不知道那位達人能指點一二。