Hibernate连接池

        <!-- datasource config -->        <property name="connection.url">jdbc:mysql://localhost:3306/db?useUnipre=true&amp;characterEncoding=UTF-8&amp;autoReconnect=true</property>        <property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>        <property name="connection.username">user</property>        <property name="connection.password">pass</property>        <!-- c3p0 config http://www.hibernate.org/214.html -->        <property name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>     <property name="hibernate.c3p0.acquire_increment">1</property>        <property name="hibernate.c3p0.idle_test_period">60</property>        <property name="hibernate.c3p0.min_size">1</property>        <property name="hibernate.c3p0.max_size">2</property>        <property name="hibernate.c3p0.max_statements">50</property>        <property name="hibernate.c3p0.timeout">0</property>        <property name="hibernate.c3p0.acquireRetryAttempts">1</property>        <property name="hibernate.c3p0.acquireRetryDelay">250</property>        <property name="hibernate.show_sql">true</property>        <property name="hibernate.use_sql_comments">true</property>        <property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>        <property name="hibernate.current_session_context_class">thread</property>        ...    </session-factory></hibernate-configuration>