java - Spring应用程序监听器-ContextRefreshedEvent java :comp/env/jdbc/db not found

Question

我试图在应用程序首次启动时进行一些数据库清理。 首先，我定义了 JNDI 连接，如下所示:

@Bean
public TomcatEmbeddedServletContainerFactory tomcatFactory() {
    return new TomcatEmbeddedServletContainerFactory() {

        @Override
        protected TomcatEmbeddedServletContainer getTomcatEmbeddedServletContainer(
                Tomcat tomcat) {
            tomcat.enableNaming();
            return super.getTomcatEmbeddedServletContainer(tomcat);
        }

        @Override
        protected void postProcessContext(Context context) {
            ContextResource resource = new ContextResource();
            resource.setName("jdbc/myDataSource");
            resource.setType(DataSource.class.getName());
            resource.setProperty("driverClassName", "your.db.Driver");
            resource.setProperty("url", "jdbc:yourDb");

            context.getNamingResources().addResource(resource);
        }
    };
}

然后我希望在ApplicationListener ContextRefreshedEvent中检索资源，ApplicationListener实现如下:

@Component
public class StartupConfiguration implements ApplicationListener<ContextRefreshedEvent>
{
    @Override
    public void onApplicationEvent(ContextRefreshedEvent event)
    {
        ApplicationContext ctx = event.getApplicationContext();

        Context initialContext = new InitialContext();
        DataSource datasource = (DataSource) initialContext.lookup("java:comp/env/jdbc/myDataSource");
        ...
    }

}

问题是它无法找到 java:comp/env/jdbc/myDataSource，我已经使用各种事件进行了测试，唯一有效的事件是在我所做的 RequestHandledEvent 中不认为这是一个好的解决方案。

Answer 1

我在以下堆栈溢出问题中找到了答案 stackoverflow.com/questions/27822619

我会引用安迪·威尔金森

Tomcat uses the thread's context class loader to determine the JNDI context to perform the lookup against. If the thread context class loader isn't the web app classloader then the JNDI context is empty, hence the lookup failure.

安迪·威尔金森建议的修复

@Bean
public TomcatEmbeddedServletContainerFactory tomcatFactory() {
return new TomcatEmbeddedServletContainerFactory() {

    @Override
    protected TomcatEmbeddedServletContainer getTomcatEmbeddedServletContainer(
            Tomcat tomcat) {
        tomcat.enableNaming();
        TomcatEmbeddedServletContainer container = 
                super.getTomcatEmbeddedServletContainer(tomcat);
        for (Container child: container.getTomcat().getHost().findChildren()) {
            if (child instanceof Context) {
                ClassLoader contextClassLoader = 
                        ((Context)child).getLoader().getClassLoader();
                Thread.currentThread().setContextClassLoader(contextClassLoader);
                break;
            }
        }
        return container;
    }

    @Override
    protected void postProcessContext(Context context) {
        ContextResource resource = new ContextResource();
        resource.setName("jdbc/myDataSource");
        resource.setType(DataSource.class.getName());
        resource.setProperty("driverClassName", "your.db.Driver");
        resource.setProperty("url", "jdbc:yourDb");

        context.getNamingResources().addResource(resource);
    }
};
}