Artifact SSMwar exploded Error deploying artifact.See server log for details

Add a Listener to web.xml today and an exception occurred

The artifact deployment failed when the Tomcat server started

Check the log to see that the bean that references the dao layer is not injected:

org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'ProductTypeService' available

At this time, it is necessary to check whether the relevant bean injection is completed. When looking at the code, it is found that a bean injection is indeed missing:

Bean injection was added manually:

I thought it would be recognized at this time, but surprisingly, the same error is still reported!

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Think about it carefully and check the code of my listener. The listener implements the ServletContextListener interface and is a global listener, that is, it will take effect as soon as the project is started, so I added an output message, which is "Enter the listener."

import com.konan.pojo.ProductType;import com.konan.service.ProductTypeService;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import javax.servlet.ServletContextEvent;import javax.servlet.ServletContextListener;import java.util.List;public class ProductTypeListener implements ServletContextListener {@Overridepublic void contextInitialized(ServletContextEvent sce) {System.out.println("Enter listener");ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext_*.xml");ProductTypeService productTypeService = (ProductTypeService) context.getBean("ProductTypeService");List allType = productTypeService.getAllType();System.out.println(allType);sce.getServletContext().setAttribute("typeList",allType);}@Overridepublic void contextDestroyed(ServletContextEvent sce) {}}

Restart the viewing console:

You can see that the listener takes effect after the artifact is deployed, but the artifact has not yet been deployed!

The same error was reported later

Why is the injected bean ProductTypeService not recognized at this time?Obviously it has been injected!

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What the listener needs to get is the bean of the ProductTypeService business layer, which is the upper interface of ProductTypeServiceImpl.Due to the early effective time of the listener, the reference name of the bean we automatically injected has not yet taken effect (in fact, the bean has been injected, but the listener cannot recognize it at this time, and the initial letter of the lowercase class name is also useless).It's time to use a custom bean name!

Add @Service("bean")

• Custom bean name, you can specify it like @Service("aaaaa"), this bean is singleton by default
• The default name when not specified is the class name (initial lowercase),

Finally modified to the following form to run normally!

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