hibernate二級快取測試

阿新 • • 發佈：2019-01-16

SessionFactory類：


import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.stat.Statistics;

public class HibernateSessionFactory {

    private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";
    private static final 
 ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
    private static Configuration configuration = new Configuration();
    private static SessionFactory sessionFactory;
    private static String configFile = CONFIG_FILE_LOCATION;
    static {
        sessionFactory = configuration.configure(configFile).buildSessionFactory();
    }

    private 
 HibernateSessionFactory(){

    }

    public static Session getSession(){
        Session session = threadLocal.get();
        if(session == null || !session.isOpen()){
            session = (sessionFactory != null) ? sessionFactory.openSession():null;
            threadLocal.set(session);
        }
        return 
 session;
    }

    public static Statistics getstat(){
        return sessionFactory.getStatistics();
    }

    public static void close(){
        sessionFactory.close();
    }

}

在Stu.hbm.xml中加入（必須在配置id前完成）

<cache usage="read-write"/>

在hibernate.cfg.xml加入二級快取配置

<!-- 設定二級快取外掛EHCache的Provider類-->
        <property name="hibernate.cache.provider_class">
            net.sf.ehcache.hibernate.EhCacheProvider
        </property>
        <!-- 啟動"查詢快取" -->
        <property name="hibernate.cache.use_query_cache">
          true
        </property>

        <!-- 快取記憶體提供程式 -->  
        <property name="hibernate.cache.region.factory_class"> 
        org.hibernate.cache.ehcache.EhCacheRegionFactory 
      </property>

<!-- 開啟二級快取 --> 
        <property name="hibernate.cache.use_second_level_cache">true</property>
         <!-- 強制Hibernate以更人性化的格式將資料存入二級快取 -->  
        <property name="hibernate.cache.use_structured_entries">true</property> 

        <property name="current_session_context_class">thread</property>
        <property name="hibernate.generate_statistics">true</property>

Scenario1：
開啟查詢快取，開啟二級快取

import model.Stu;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.stat.Statistics;

public class CacheTest {

    public static void main(String[] args) {
        eacheTest();
    }

    public static void eacheTest(){
        Session s1 = HibernateSessionFactory.getSession();
        s1.beginTransaction();
        System.out.println("Search Stu first time.");
        Query q = s1.createQuery("from Stu");
        //啟用查詢快取
        //Enable/disable second level query (result) caching for this query.
        q.setCacheable(true);
        q.list();
//      q.iterate();

        System.out.println("put int level-two eache.");
        s1.getTransaction().commit();
        s1.close();

        System.out.println("-------------------------------------");

        Session s2 = HibernateSessionFactory.getSession();
        s2.beginTransaction();
        System.out.println("Search Stu second time, don't execute sql");
        Query q2 = s2.createQuery("from Stu");
        //啟用查詢快取
        q2.setCacheable(true);
        q2.list();
//      q2.iterate();
        s2.getTransaction().commit();
        s2.close();

        System.out.println("-------------------------------------");

        Session s3 = HibernateSessionFactory.getSession();
        Stu  stu = (Stu) s3.get(Stu.class, 1);
        Stu  stu2 = (Stu) s3.get(Stu.class, 1);
        Stu stu3 = (Stu)s3.get(Stu.class, 2);
        System.out.println(stu.getSname());
        System.out.println(stu2.getSname());
        System.out.println(stu3.getSname());
        s3.close();

        System.out.println("-------------------------------------");

        Statistics s = HibernateSessionFactory.getstat();
        s.logSummary();

        HibernateSessionFactory.close();
    }
}

執行結果：

Search Stu first time.
08-13 16:23:25.772 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking cached query results in region: org.hibernate.cache.internal.StandardQueryCache
08-13 16:23:25.772 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2
08-13 16:23:25.772 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - Element for key sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2 is null
08-13 16:23:25.773 org.hibernate.cache.internal.StandardQueryCache DEBUG - Query results were not found in cache
Hibernate: 
    select
        stu0_.sno as sno1_2_,
        stu0_.sname as sname2_2_,
        stu0_.sex as sex3_2_,
        stu0_.age as age4_2_,
        stu0_.sdept as sdept5_2_ 
    from
        test.stu stu0_
08-13 16:23:25.841 org.hibernate.cache.internal.StandardQueryCache DEBUG - Caching query results in region: org.hibernate.cache.internal.StandardQueryCache; timestamp=5896004427124736
08-13 16:23:25.842 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2 value: [5896004427124736, 1, 2, 3, 4, 6, 7]
put int level-two eache.
08-13 16:23:25.851 org.hibernate.engine.internal.StatisticalLoggingSessionEventListener INFO  - Session Metrics {
    29941 nanoseconds spent acquiring 1 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    17828019 nanoseconds spent preparing 1 JDBC statements;
    1520136 nanoseconds spent executing 1 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    8472812 nanoseconds spent performing 7 L2C puts;
    0 nanoseconds spent performing 0 L2C hits;
    568019 nanoseconds spent performing 1 L2C misses;
    6330335 nanoseconds spent executing 1 flushes (flushing a total of 6 entities and 0 collections);
    62448 nanoseconds spent executing 1 partial-flushes (flushing a total of 0 entities and 0 collections)
}
-------------------------------------
Search Stu second time, don't execute sql
08-13 16:23:25.854 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking cached query results in region: org.hibernate.cache.internal.StandardQueryCache
08-13 16:23:25.855 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2
08-13 16:23:25.855 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking query spaces are up-to-date: [test.stu]
08-13 16:23:25.855 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: test.stu
08-13 16:23:25.855 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - Element for key test.stu is null
08-13 16:23:25.855 org.hibernate.cache.internal.StandardQueryCache DEBUG - Returning cached query results
08-13 16:23:25.863 org.hibernate.engine.internal.StatisticalLoggingSessionEventListener INFO  - Session Metrics {
    8554 nanoseconds spent acquiring 1 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    0 nanoseconds spent preparing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    0 nanoseconds spent performing 0 L2C puts;
    2024852 nanoseconds spent performing 7 L2C hits;
    233966 nanoseconds spent performing 1 L2C misses;
    432003 nanoseconds spent executing 1 flushes (flushing a total of 6 entities and 0 collections);
    8127 nanoseconds spent executing 1 partial-flushes (flushing a total of 0 entities and 0 collections)
}
-------------------------------------
zhs
zhs
lisi
08-13 16:23:25.866 org.hibernate.engine.internal.StatisticalLoggingSessionEventListener INFO  - Session Metrics {
    0 nanoseconds spent acquiring 0 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    0 nanoseconds spent preparing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    0 nanoseconds spent performing 0 L2C puts;
    68864 nanoseconds spent performing 2 L2C hits;
    0 nanoseconds spent performing 0 L2C misses;
    0 nanoseconds spent executing 0 flushes (flushing a total of 0 entities and 0 collections);
    0 nanoseconds spent executing 0 partial-flushes (flushing a total of 0 entities and 0 collections)
}
-------------------------------------
08-13 16:23:25.866 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000161: Logging statistics....
08-13 16:23:25.866 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000251: Start time: 1439454205398
08-13 16:23:25.866 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000242: Sessions opened: 3
08-13 16:23:25.866 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000241: Sessions closed: 3
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000266: Transactions: 2
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000258: Successful transactions: 2
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000187: Optimistic lock failures: 0
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000105: Flushes: 2
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000048: Connections obtained: 2
08-13 16:23:25.867 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000253: Statements prepared: 1
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000252: Statements closed: 0
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000239: Second level cache puts: 6
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000237: Second level cache hits: 8
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000238: Second level cache misses: 0
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000079: Entities loaded: 6
08-13 16:23:25.868 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000080: Entities updated: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000078: Entities inserted: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000076: Entities deleted: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000077: Entities fetched (minimize this): 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000033: Collections loaded: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000036: Collections updated: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000035: Collections removed: 0
08-13 16:23:25.869 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000034: Collections recreated: 0
08-13 16:23:25.870 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000032: Collections fetched (minimize this): 0
08-13 16:23:25.870 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000438: NaturalId cache puts: 0
08-13 16:23:25.870 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000439: NaturalId cache hits: 0
08-13 16:23:25.870 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000440: NaturalId cache misses: 0
08-13 16:23:25.870 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000441: Max NaturalId query time: 0ms
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000442: NaturalId queries executed to database: 0
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000210: Queries executed to database: 1
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000215: Query cache puts: 1
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000433: update timestamps cache puts: 0
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000434: update timestamps cache hits: 0
08-13 16:23:25.871 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000435: update timestamps cache misses: 1
08-13 16:23:25.872 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000213: Query cache hits: 1
08-13 16:23:25.872 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000214: Query cache misses: 1
08-13 16:23:25.872 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000173: Max query time: 67ms
08-13 16:23:25.885 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl INFO  - HHH000030: Cleaning up connection pool [jdbc:mysql://localhost:3306/test]

Scenario2：
開啟查詢快取，關閉二級快取。

執行結果：

Search Stu first time.
08-13 17:10:58.560 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking cached query results in region: org.hibernate.cache.internal.StandardQueryCache
08-13 17:10:58.560 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2
08-13 17:10:58.560 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - Element for key sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2 is null
08-13 17:10:58.561 org.hibernate.cache.internal.StandardQueryCache DEBUG - Query results were not found in cache
Hibernate: 
    select
        stu0_.sno as sno1_2_,
        stu0_.sname as sname2_2_,
        stu0_.sex as sex3_2_,
        stu0_.age as age4_2_,
        stu0_.sdept as sdept5_2_ 
    from
        test.stu stu0_
08-13 17:10:58.620 org.hibernate.cache.internal.StandardQueryCache DEBUG - Caching query results in region: org.hibernate.cache.internal.StandardQueryCache; timestamp=5896016112107520
08-13 17:10:58.621 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2 value: [5896016112107520, 1, 2, 3, 4, 6, 7]
-------------------------------------
Search Stu second time, don't execute sql
08-13 17:10:58.632 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking cached query results in region: org.hibernate.cache.internal.StandardQueryCache
08-13 17:10:58.632 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: sql: select stu0_.sno as sno1_2_, stu0_.sname as sname2_2_, stu0_.sex as sex3_2_, stu0_.age as age4_2_, stu0_.sdept as sdept5_2_ from test.stu stu0_; parameters: ; named parameters: {}; transformer: [email protected]110f2
08-13 17:10:58.632 org.hibernate.cache.internal.StandardQueryCache DEBUG - Checking query spaces are up-to-date: [test.stu]
08-13 17:10:58.632 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - key: test.stu
08-13 17:10:58.632 org.hibernate.cache.ehcache.internal.regions.EhcacheGeneralDataRegion DEBUG - Element for key test.stu is null
08-13 17:10:58.633 org.hibernate.cache.internal.StandardQueryCache DEBUG - Returning cached query results
-------------------------------------
zhs
zhs
lisi
-------------------------------------
08-13 17:10:58.641 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000161: Logging statistics....
08-13 17:10:58.641 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000251: Start time: 1439457058255
08-13 17:10:58.641 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000242: Sessions opened: 0
08-13 17:10:58.641 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000241: Sessions closed: 0
08-13 17:10:58.641 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000266: Transactions: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000258: Successful transactions: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000187: Optimistic lock failures: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000105: Flushes: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000048: Connections obtained: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000253: Statements prepared: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000252: Statements closed: 0
08-13 17:10:58.642 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000239: Second level cache puts: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000237: Second level cache hits: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000238: Second level cache misses: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000079: Entities loaded: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000080: Entities updated: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000078: Entities inserted: 0
08-13 17:10:58.643 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000076: Entities deleted: 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000077: Entities fetched (minimize this): 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000033: Collections loaded: 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000036: Collections updated: 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000035: Collections removed: 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000034: Collections recreated: 0
08-13 17:10:58.644 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000032: Collections fetched (minimize this): 0
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000438: NaturalId cache puts: 0
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000439: NaturalId cache hits: 0
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000440: NaturalId cache misses: 0
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000441: Max NaturalId query time: 0ms
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000442: NaturalId queries executed to database: 0
08-13 17:10:58.645 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000210: Queries executed to database: 0
08-13 17:10:58.646 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000215: Query cache puts: 0
08-13 17:10:58.646 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000433: update timestamps cache puts: 0
08-13 17:10:58.646 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000434: update timestamps cache hits: 0
08-13 17:10:58.646 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000435: update timestamps cache misses: 0
08-13 17:10:58.647 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000213: Query cache hits: 0
08-13 17:10:58.647 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000214: Query cache misses: 0
08-13 17:10:58.647 org.hibernate.stat.internal.ConcurrentStatisticsImpl INFO  - HHH000173: Max query time: 0ms
08-13 17:10:58.656 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl INFO  - HHH000030: Cleaning up connection pool [jdbc:mysql://localhost:3306/test]

從兩次的執行結果的日誌對比發現，Scenario1中的第二次查詢使用的是二級快取中的快取，從日誌中也可以看到命中的次數。Scenario2中第二次查詢使用的是查詢快取中的快取。

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