Question

我的application-datasource.xmls低于我的问题是我不想在此提供用户名和密码上下文文件我想在用户登录时获取运行时的用户名和密码，但我不知道如何操作这样做。

    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="
    http://www.springframework.org/schema/beans http://www.springframework.org/schem...-beans-2.0.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schem...ng-aop-2.0.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">

    <tx:annotation-driven />
    <!-- DataSource has been Lazily initialized, set lazy-init to false in production -->

    <bean id="datasource"
    class="com.mchange.v2.c3p0.ComboPooledDataSource" lazy-init="true" destroy-method="close">
    <!-- Tracker created for connection problem: https://sourceforge.net/tracker/?func=detail&aid=3176467&group_id=25357&atid=38369 0-->
    <property name="driverClass" value="com.ibm.as400.access.AS400JDBCDriver" />
    <property name="jdbcUrl" value="${url}" />
    <!--<property name="user" value="${username}" />
    <property name="password" value="${password}" />-->

    <!-- Pool Size Properties follow -->
    <property name="minPoolSize" value="0"/> <!-- Minimum no. of pooled connections -->
    <property name="initialPoolSize" value="1" /> <!-- Initial no. of pooled connections (>minimum)[optional] -->
    <property name="maxPoolSize" value="2"/> <!-- Maximum no. of pooled connections (>minimum) -->
    <property name="acquireIncrement" value="1"/> <!-- Connections to be added every time the need arises -->

    <!-- Connection Establishment Strategy follows -->
    <property name="acquireRetryAttempts" value="5" /> <!-- Retry Attempts on Database connection failure -->
    <property name="acquireRetryDelay" value="1000"/> <!-- Milliseconds between re-tries -->
    <property name="breakAfterAcquireFailure" value="true" /> <!-- Aggressively break DataSource on connection failure -->

    <!-- Prepared Statement pooling -->
    <property name="maxStatements" value="300"/> <!-- Value ~= maxPoolSize * no. of (frequently used)stored procedures -->
    <property name= "maxStatementsPerConnection" value="15" /> <!-- Statement caching per connection for improved performance -->

    <!-- Connection Age related settings -->
    <property name="maxIdleTime" value="300" /> <!-- Seconds for a connection to remain idle before being closed -->
    <property name="unreturnedConnectionTimeout" value="300" /> <!-- Wait for number of seconds for application to release a connection -->

    <property name="idleConnectionTestPeriod" value="30000"/> <!-- Test for idle connections(In milliseconds) -->
    <property name= "autoCommitOnClose" value="true" /> <!-- For ensuring all transactions to commit/rollback on close -->
    <property name="debugUnreturnedConnectionStackTraces" value ="true" />
    <!-- Ignored overrides -->

    <!-- Used for connection testing during startup -->
    <!--property name="testConnectionOnCheckin" value="true" /--> <!-- Test for connection validity asynchronously -->

    <!--property name="initialPoolSize" value="1" /--> <!-- Initial no. of pooled connections (>minimum)[optional] -->
    <!--property name="idleConnectionTestPeriod" value="30000" /> In milliseconds(Overridden) -->
    <!--property name="maxConnectionAge" value="1800" /--> <!-- Life in seconds for any connection(busy/idle) before being deleted -->
    <!--property name="numHelperThreads" value="3" /--> <!-- Perform JDBC operations asynchronously -->

    <bean id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalContainerE ntityManagerFactoryBean">
    <property name="persistenceUnitName" value="persistence" />
    <property name="persistenceXmlLocation" value="classpathersistence.xml" />
    <property name="dataSource" ref="datasource" />
    <property name="loadTimeWeaver">
    <bean class="org.springframework.instrument.classloading .InstrumentationLoadTimeWeaver" />
    </property>
    <property name="jpaVendorAdapter" ref="vendorAdapter" />
    </bean>

    <bean id="vendorAdapter"
    class="org.springframework.orm.jpa.vendor.Hibernat eJpaVendorAdapter">
    <property name="databasePlatform" value="${dialect}" />
    <property name="showSql" value="${show_sql}" />
    <property name="generateDdl" value="false" />
    </bean>

<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionM anager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>

<bean class="org.springframework.orm.jpa.support.Persist enceAnnotationBeanPostProcessor" />
<bean class="org.springframework.dao.annotation.Persiste nceExceptionTranslationPostProcessor"/>
</beans>

有些网站建议使用UserCredintialDataSource但它实际上不起作用我想刷新entitymanagerfactory所以它可以使我在当前场景中使用新连接的实体对象它给出错误无法在获取数据时打开连接。感谢

Answer 1

EntityManagerFactory是全局的，所以你提出的建议不会很好。如果刷新（即重新创建）EnitytManagerFactory，那将影响整个应用程序，而不仅仅是当前请求/线程/用户。如果您希望真正拥有每个用户的不同数据库凭据，Hibernate不是您的最佳选择。您基本上必须为每个会话创建一个唯一的EntityManagerFactory，这会产生大量的性能开销和内存重复。您也不能使用连接池，因为无论如何您都需要为每个用户打开一个新连接。

我的建议，重新考虑您的要求和您的架构。如果您无法远离数据库中的用户凭据并且必须使用Hibernate，那么您将不得不在性能，内存和复杂性方面受到重创，因为您需要为每个用户会话打开和关闭新的entitymanagerfactories。 / p>

即时刷新实体管理器工厂

1 个答案: