Himai Minh

Hi, Labzar,
Is there any Spring Practice Exam desktop version?
The one you shared with us is on Android.

Hi,
From the Pivotal's study guide of Spring 5 professional certification exam, I don't see it mention Spring WebFlux or reactive programming which are new to Spring 5.
Are they on the exam?
Just want to confirm with some of you who took the exam.

Hi, Dominik,
I just bought your tutorial module 1 and I am studying on it  now
I can't wait to see module 2 - 8 available. Would you mind posting them soon?
Thanks.

Hi, I came across two examples from Spring in Action and Getting Started with Spring Framework.
One example uses new ClassPathXmlApplicationContext ("META-INFO/spring/knight.xml") and the other one uses new ClassPathXmlApplication("classpath:META-INFO/spring/applicationContext.xml")
Both knight.xml and applicationContext.xml are in resources/META-INFO/spring.
Both example works
I assume classpath prefix is always needed as the xml config file is under resources/META-INFO folder.
But why the classpath is needed in one example, but not the other?
The examples are here:
https://github.com/habuma/spring-in-action-4-samples/blob/master/Chapter_01/knight/src/main/java/sia/knights/KnightMain.java
https://github.com/getting-started-with-spring/4thEdition/blob/master/chapter%206/ch06-bean-profiles/src/main/java/sample/spring/chapter06/bankapp/BankAppWithProfile.java

Thanks in advance.

Hi, I find a fix to my code, but I don't think my fix is perfect. If anyone has a better solution, please let me know.
In the applicationContext.xml, I add the viewResolver:
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/mvc  http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context        http://www.springframework.org/schema/context/spring-context.xsd"> <mvc:annotation-driven /> <context:component-scan base-package="sample.spring.chapter12" />       <!-- I have to add this to make it work, but it is only supposed to be in the bankapp-servlet.xml --> <bean id="viewResolver"  class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> </beans>

This is my bankapp-servlet.xml
<beans xmlns="http://www.springframework.org/schema/beans"   xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc        http://www.springframework.org/schema/mvc/spring-mvc.xsd  http://www.springframework.org/schema/context        http://www.springframework.org/schema/context/spring-context.xsd "> <mvc:annotation-driven /> <context:component-scan base-package="sample.spring.chapter12.web" /> <bean id="viewResolver"  class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> </beans>

I committed my code there :
https://github.com/aCodeRancher/4thEdition/tree/my-bank-app/chapter%2012/ch12-bankapp

Hi, I am trying to replace web.xml in ch12-bankapp example of Getting Started With SpringFramework 4th edition.
This is the web.xml provided in the book:
<context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:/META-INF/spring/applicationContext.xml </param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener </listener-class> </listener> <servlet> <servlet-name>bankapp</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet </servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/spring/bankapp-config.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>bankapp</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping>

I converted it into Java code:
public class MyXMLWebAppInitializer implements WebApplicationInitializer {    @Override    public void onStartup (ServletContext container)  {         XmlWebApplicationContext   appContext = new XmlWebApplicationContext();        appContext.setConfigLocation("classpath*:/META-INF/spring/applicationContext.xml");            appContext.setServletContext(container);              DispatcherServlet theDispatcherServlet = new DispatcherServlet(appContext);         //I change the name of bankapp-config.xml to bankapp-servlet.xml        theDispatcherServlet.setContextConfigLocation("/WEB-INF/spring/bankapp-servlet.xml");        ServletRegistration.Dynamic theServletRegistration =               container.addServlet("bankapp", theDispatcherServlet);        theServletRegistration.setLoadOnStartup(1);        theServletRegistration.addMapping("/");    } }


This is the Tomcat 9 log :
 29-Mar-2019 21:40:45.061 INFO [RMI TCP Connection(3)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time. INFO  org.springframework.web.context.support.XmlWebApplicationContext - Refreshing Root WebApplicationContext: startup date [Fri Mar 29 21:40:46 EDT 2019]; root of context hierarchy INFO  org.springframework.beans.factory.xml.XmlBeanDefinitionReader - Loading XML bean definitions from URL [file:/C:/Users/Downloads/apache-tomcat-9.0.11/webapps/ch12/WEB-INF/classes/META-INF/spring/applicationContext.xml] INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit],methods=[POST],params=[fdAction=edit]}" onto public org.springframework.web.servlet.ModelAndView sample.spring.chapter12.web.FixedDepositController.editFixedDeposit(org.springframework.util.MultiValueMap<java.lang.String, java.lang.String>) INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit],methods=[POST],params=[fdAction=create]}" onto public org.springframework.web.servlet.ModelAndView sample.spring.chapter12.web.FixedDepositController.openFixedDeposit(java.util.Map<java.lang.String, java.lang.String>) INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit/list],methods=[GET]}" onto public org.springframework.web.servlet.ModelAndView sample.spring.chapter12.web.FixedDepositController.listFixedDeposits() INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit],methods=[POST],params=[fdAction=createFDForm]}" onto public org.springframework.web.servlet.ModelAndView sample.spring.chapter12.web.FixedDepositController.showOpenFixedDepositForm() INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit],methods=[GET],params=[fdAction=close]}" onto public java.lang.String sample.spring.chapter12.web.FixedDepositController.closeFixedDeposit(int) INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping - Mapped "{[/fixedDeposit],methods=[GET],params=[fdAction=view]}" onto public org.springframework.web.servlet.ModelAndView sample.spring.chapter12.web.FixedDepositController.viewFixedDepositDetails(javax.servlet.http.HttpServletRequest) INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter - Looking for @ControllerAdvice: Root WebApplicationContext: startup date [Fri Mar 29 21:40:46 EDT 2019]; root of context hierarchy INFO  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter - Looking for @ControllerAdvice: Root WebApplicationContext: startup date [Fri Mar 29 21:40:46 EDT 2019]; root of context hierarchy INFO  org.springframework.web.servlet.DispatcherServlet - FrameworkServlet 'bankapp': initialization started INFO  org.springframework.web.servlet.DispatcherServlet - FrameworkServlet 'bankapp': initialization completed in 123 ms [2019-03-29 09:40:50,280] Artifact ch12-bankapp:war: Artifact is deployed successfully [2019-03-29 09:40:50,280] Artifact ch12-bankapp:war: Deploy took 8,847 milliseconds 29-Mar-2019 21:40:51.080 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [C:\Users\Downloads\apache-tomcat-9.0.11\webapps\manager] 29-Mar-2019 21:40:51.211 INFO [ContainerBackgroundProcessor[StandardEngine[Catalina]]] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [C:\Users\Downloads\apache-tomcat-9.0.11\webapps\manager] has finished in [131] ms WARN  org.springframework.web.servlet.PageNotFound - No mapping found for HTTP request with URI [/ch12/fixedDeposit/fixedDepositList] in DispatcherServlet with name 'bankapp'

I cannot get any result from the browser.
If anyone knows, please help. Thanks.
This is my detailed code in GitHub:
https://github.com/aCodeRancher/4thEdition/tree/master/chapter%2012/ch12-bankapp

I don't know why I need to use AbstractAnnotationConfigDispatcherServletInitializer and a subclass of a deprecated class, WebMvcConfigurerAdapter to make it work.
But I don't want to use the deprecated class.
My code is here:
https://github.com/aCodeRancher/4thEdition/tree/myfeature_1/chapter%2012/ch12-bankapp/src/main/java/sample/spring/chapter12/config

Hi, I am trying to replace the web.xml by WebApplicationInitializer in chapter 12's bankapp of Getting Started with Spring Framework 5 , 4th edition.
But I got an error from Tomcat 9:

The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.

What I added are:
.... @Configuration @ComponentScan(basePackages="sample.spring.chapter12") public class AppConfig { }
public class MyXMLWebAppInitializer implements WebApplicationInitializer {    @Override    public void onStartup (final ServletContext inServletContext){        final XmlWebApplicationContext theXmlWebApplicationContext =                new XmlWebApplicationContext();        theXmlWebApplicationContext.setConfigLocation("/WEB-INF/spring/bank-config.xml");        inServletContext.addListener(new ContextLoaderListener(theXmlWebApplicationContext));        theXmlWebApplicationContext.setServletContext(inServletContext);        theXmlWebApplicationContext.refresh();        theXmlWebApplicationContext.start();        final DispatcherServlet theDispatcherServlet =                new DispatcherServlet(theXmlWebApplicationContext);        ServletRegistration.Dynamic theServletRegistration =                inServletContext.addServlet("bankapp", theDispatcherServlet);        theServletRegistration.setLoadOnStartup(1);        theServletRegistration.addMapping("/");    } }
@Configuration @EnableWebMvc public class WebConfig extends WebMvcConfigurerAdapter { }

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc        http://www.springframework.org/schema/mvc/spring-mvc.xsd  http://www.springframework.org/schema/context        http://www.springframework.org/schema/context/spring-context.xsd "> <mvc:annotation-driven /> <context:component-scan base-package="sample.spring.chapter12.domain, sample.spring.chapter12.dao, sample.spring.chapter12.service,            sample.spring.chapter12.config, sample.spring.chapter12.web" /> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> </beans>
The detailed code is here :
https://github.com/aCodeRancher/4thEdition/tree/myfeature/chapter%2012/ch12-bankapp


If anyone has suggestion to fix it, please help. Thanks in advanced.

Hi, I tried it.
I have two overloading methods annotated with @Bean. They have different @Profile. To my surprise, the second bean in the file is autowired, not the first one.

Hi,
According to the Spring 5 documentation section 1.13.1

With @Profile on @Bean methods, a special scenario may apply: In the case of overloaded @Bean methods of the same Java method name (analogous to constructor overloading), an @Profile condition needs to be consistently declared on all overloaded methods.
If the conditions are inconsistent, only the condition on the first declaration among the overloaded methods will matter.

If methods are overloaded, that means the methods return beans of the same type. The container does not know which bean to inject or autowire in this situation even if the active profile is set.
I think using @Primary on one of the bean methods can tell the container which bean to inject. The order of methods' declaration does not matter as the document describes.

Reference:
https://docs.spring.io/spring/docs/5.0.3.RELEASE/spring-framework-reference/core.html#beans-definition-profiles

I add one more test case with two beans with @Profile ("english"). And in this case, I have to set one of them as @Primary; otherwise, the container does not know which one to inject.
public class HelloConfig {        @Bean (name = "englishbean")    @Profile("english")    public HelloWorldService helloWorldServiceEnglish(HelloWorldFactory factory){              return factory.createHelloWorldService("en");    }    @Bean (name = "englishbeanUS")    @Profile("english")    @Primary    public HelloWorldService helloWorldServiceEnglish1(HelloWorldFactory factory){              return factory.createHelloWorldService("enUS");    }
It seems like in any case when the container cannot determine which bean to inject, we have to use @Primary.
The source code is committed here https://github.com/aCodeRancher/diexample/tree/advanced-autowire/src

Hi, Jain. Thanks for your suggestion.
It seems to me that we can draw these conclusion:
1. With beans of different name, same type , use @Primary and @Profile
2. With beans of the same name, same type, omit @Primary, @Profile is good enough.

Hi everyone,
I have a gut's feeling that @Profile is only used for the method/class when a particular profile is set to be active. It has nothing to do with the bean.
For example,
@Profile ("english") public String getEnglishHelloWorld(){   return "hello"; } @Profile ("spanish") public String getSpanishHelloWorld(){ return "hola"; }
When the active profile is english, then the first method is chosen.

But since the method registers a bean, that is a different story. The container needs to choose one of them. In this particular case, both beans have the same priority. The container will choose either one depends on the active profile.
@Profile ("english") @Bean @Primary public  HelloWorldService getHelloWorld() { ....} @Profile ("spanish") @Bean @Primary public HelloWorldSerivce getHelloWorldinSpanish() {... }

Any other comments ?  Correct me if I am wrong.
Thanks.

Hi, Jain,
My toy code is https://github.com/aCodeRancher/diexample/tree/advanced-autowire

@SpringBootApplication @ComponentScan("guru.springframework") public class DependencyInjectionApplication {    public static void main(String[] args) {        ApplicationContext ctx = SpringApplication.run(DependencyInjectionApplication.class, args);        GreetingController controller = (GreetingController) ctx.getBean("greetingController");        controller.sayHello(); }

@Configuration public class HelloConfig {    @Bean    public HelloWorldFactory helloWorldFactory(){        return new HelloWorldFactory();    }    @Bean    @Profile("english")    @Primary    public HelloWorldService helloWorldServiceEnglish(HelloWorldFactory factory){        return factory.createHelloWorldService("en");    }    @Bean    @Profile("spanish")    @Primary    public HelloWorldService helloWorldServiceSpanish(HelloWorldFactory factory){        return factory.createHelloWorldService("es");    }    @Bean(name = "french")    public HelloWorldService helloWorldServiceFrench(HelloWorldFactory factory){        return factory.createHelloWorldService("fr");    }    ....

@Controller public class GreetingController {    private HelloWorldService helloWorldService;  ...    @Autowired    public void setHelloWorldService(HelloWorldService helloWorldService) {        this.helloWorldService = helloWorldService;    }   ...

//in application.properties, english is the active profile spring.profiles.active=english

So, in this case, the english profile is active. The container can simply choose the @Profile("english") bean. But it does not work because there are two helloWorldService beans. I have to set at least one of them @Primary.
My question is if the bean has been annotated with @Profile ("english"), why the container still does not know which bean to choose?

Hi, I configure two beans in a class annotated with @Configuration:
   
   @Bean
   @Profile("english")
   
   public HelloWorldService helloWorldEnglish(){
       ....
   }

   @Bean
   @Profile("spanish")
   @Primary
   public HelloWorldService helloWorldServiceSpanish(){
     ...
   }
My application.properties define spring.profiles.active = english
But it still complains that more than one bean is found.
I have to put @Primary to the helloWorldEnglish bean to make it work.
My question is why should I put @Primary to autowire the right bean even though my profile has been set to english ?