为什么使用 JndiObjectFactoryBean 配置 JNDI 数据源不起作用?

why use JndiObjectFactoryBean to config JNDI datasource did not work?

当我使用 Java-base 来配置我的 JNDI 时。 Spring4.2.5.

但是如果我使用 JndiObjectFactoryBean config.when 我想得到 datasource,对象将为空。

@Bean
    public DataSource dataSource(){
        JndiObjectFactoryBean jndiObjectFactoryBean =new JndiObjectFactoryBean();
        jndiObjectFactoryBean.setJndiName("jdbc/SpittrDS");
        jndiObjectFactoryBean.setResourceRef(true);
        jndiObjectFactoryBean.setProxyInterface(DataSource.class);
        return (DataSource) jndiObjectFactoryBean.getObject();  //NULL!!!
    }

但是如果把方法改成这个,效果很好。

@Bean
    public DataSource dataSource(){
        final JndiDataSourceLookup dsLookup = new JndiDataSourceLookup();
        dsLookup.setResourceRef(true);
        DataSource dataSource = dsLookup.getDataSource("java:comp/env/jdbc/SpittrDS");
        return dataSource;
    }

不知道哪里出了问题

Tomcat 9.0 context.xml

<Context>

    <!-- Default set of monitored resources. If one of these changes, the    -->
    <!-- web application will be reloaded.                                   -->
    <WatchedResource>WEB-INF/web.xml</WatchedResource>
    <WatchedResource>${catalina.base}/conf/web.xml</WatchedResource>

    <!-- Uncomment this to disable session persistence across Tomcat restarts -->
    <!--
    <Manager pathname="" />
    -->

    <Resource name="jdbc/SpittrDS"
      auth="Container"
      type="javax.sql.DataSource"
      driverClassName="com.mysql.jdbc.Driver"
      url="jdbc:mysql://localhost:3306/spittrds"
      username="root"
      password="1"
      maxActive="100"
      maxIdle="20"
      minIdle="5"
      maxWait="10000"/>
</Context>

JndiObjectFactoryBean 中的实际查找是在生命周期回调方法中完成的。像这样在 @Bean 方法中显式调用该方法(解决方法)

    @Bean
    public DataSource dataSource(){
        JndiObjectFactoryBean jndiObjectFactoryBean =new JndiObjectFactoryBean();
        jndiObjectFactoryBean.setJndiName("jdbc/SpittrDS");
        jndiObjectFactoryBean.setResourceRef(true);
        jndiObjectFactoryBean.setProxyInterface(DataSource.class);
        jndiObjectFactoryBean.afterPropertiesSet();
        return (DataSource) jndiObjectFactoryBean.getObject();  //NULL!!!
    }

或者更好的方法。让你的@Bean 方法 return JndiObjectFactoryBean 并管理它的生命周期。然后在需要数据源的依赖 bean 中注入从工厂创建的数据源

    @Bean
    public JndiObjectFactoryBean dataSource(){
        JndiObjectFactoryBean jndiObjectFactoryBean =new JndiObjectFactoryBean();
        jndiObjectFactoryBean.setJndiName("jdbc/SpittrDS");
        jndiObjectFactoryBean.setResourceRef(true);
        jndiObjectFactoryBean.setProxyInterface(DataSource.class);
        return jndiObjectFactoryBean;
    }

//in your dependnecy

@Bean
public SomeBean someBean(DataSource dataSource){
   //use the injected datasource shich comes from the factory
}

我来到这里并没有意识到这是我过去遇到的问题 -

因此,解决方法(不是首选方法)是在尝试 getObject()

之前调用 jndiObjectFactoryBean 上的 afterPropertiesSet()
@Bean
    public DataSource dataSource(){
        JndiObjectFactoryBean jndiObjectFactoryBean =new JndiObjectFactoryBean();
        jndiObjectFactoryBean.setJndiName("jdbc/SpittrDS");
        jndiObjectFactoryBean.setResourceRef(true);
        jndiObjectFactoryBean.setProxyInterface(DataSource.class);
        jndiObjectFactoryBean.afterPropertiesSet();
        return (DataSource) jndiObjectFactoryBean.getObject();  //NOT NULL
    }

对于那些正在寻找通过 JNDI 定义数据源的方法的人,我会选择:

@Bean
public JndiObjectFactoryBean dataSource(){
    return new JndiDataSourceLookup().getDataSource("jdbc/SpittrDS");
}