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HTTP status 404 - Not Found while creating springBoot Application

This a springboot Application. It run perfectly but did not get output (it shows me HTTP Status 404 error in browser)
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.exaample.demo</groupId>
<artifactId>SpringBootMaven</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>Maven spring boot project</name>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.9.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<properties>
<java.version>1.8</java.version>
</properties>
</project>
Springboot start Class
Main Method
package com.example.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class WebMainMethod {
public static void main(String[] args) {
SpringApplication.run(WebMainMethod.class, args);
}
}
controller is loading after main class
**Rest Controller**
package com.example.demo.controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
public class HelloController {
#RequestMapping("/hello")
public String sayHi() {
return "Hi";
}
}
Url : http://localhost:8080/hello
output

Unable to reproduce problem.
This is not an answer, but I copied the 3 files from question, and built and ran code without problem. My console log is however a bit different, included below, and that's why I'm posting this as an answer.
Try doing a clean build. Maybe that will fix the problem.
Console Log
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.5.9.RELEASE)
2017-12-02 02:06:19.763 INFO 13268 --- [ main] com.example.demo.WebMainMethod : Starting WebMainMethod on XXXX with PID 13268 (C:\Users\XXXX\SpringBootMaven\target\classes started by Andreas in C:\Users\XXXX\SpringBootMaven)
2017-12-02 02:06:19.765 INFO 13268 --- [ main] com.example.demo.WebMainMethod : No active profile set, falling back to default profiles: default
2017-12-02 02:06:19.794 INFO 13268 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#4f51b3e0: startup date [Sat Dec 02 02:06:19 EST 2017]; root of context hierarchy
2017-12-02 02:06:20.631 INFO 13268 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-12-02 02:06:20.641 INFO 13268 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2017-12-02 02:06:20.642 INFO 13268 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.23
2017-12-02 02:06:20.751 INFO 13268 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-12-02 02:06:20.751 INFO 13268 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 959 ms
2017-12-02 02:06:20.824 INFO 13268 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-12-02 02:06:20.826 INFO 13268 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-12-02 02:06:20.827 INFO 13268 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-12-02 02:06:20.827 INFO 13268 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-12-02 02:06:20.827 INFO 13268 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-12-02 02:06:21.025 INFO 13268 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for #ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#4f51b3e0: startup date [Sat Dec 02 02:06:19 EST 2017]; root of context hierarchy
2017-12-02 02:06:21.071 INFO 13268 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello]}" onto public java.lang.String com.example.demo.controller.HelloController.sayHi()
2017-12-02 02:06:21.074 INFO 13268 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-12-02 02:06:21.074 INFO 13268 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-12-02 02:06:21.095 INFO 13268 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-12-02 02:06:21.095 INFO 13268 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-12-02 02:06:21.119 INFO 13268 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-12-02 02:06:21.195 INFO 13268 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-12-02 02:06:21.271 INFO 13268 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-12-02 02:06:21.273 INFO 13268 --- [ main] com.example.demo.WebMainMethod : Started WebMainMethod in 1.908 seconds (JVM running for 2.231)
2017-12-02 02:06:38.426 INFO 13268 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet 'dispatcherServlet'
2017-12-02 02:06:38.426 INFO 13268 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started
2017-12-02 02:06:38.435 INFO 13268 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 9 ms

Maybe your template doesn't exist. Please specify file name of template which map with the retured value. Check this example
#Controller
public class HelloWorldController {
#RequestMapping("/hello")
public String hello(Model model, #RequestParam(value="name", required=false, defaultValue="World") String name) {
String message="You just create Spring Boot Example successfully";
model.addAttribute("name", name);
model.addAttribute("message", message);
return "hello";
}
}
Found this from Spring Boot Maven Example Hello World

It's seems there is some problem at your port 8080.
please change port and try to restart your appliaction.
Example: Add below to your application.properties file
server.port = 8090
and then try hitting http://localhost:8090/hello

You can try this.
Using application.properties /yml
The most straightforward way of changing the context path is to set the property in the application.properties:
server.servlet.context-path=/demoApp
Instead of putting the properties file in src/main/resources, we can also keep it in the current working directory (outside of the classpath).
Java System Property.
http://localhost:8090/demoApp/hello
for more info.
https://www.baeldung.com/spring-boot-context-path

Do you create a jsp or html page called hi... Check your views... You don;t have page to view.... Please create a jsp and put it on
#RequestMapping("/hello")
public String sayHi(Model model) {
model.addAttribute("Hi","Hi")
return "Hi";
}
jsp page must be Hi

Spring Boot Security Default Password

i have a strange problem when i launch my spring application it used to print a default password to login in the browser but now ther isn't :
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.5.3.RELEASE)
2017-06-26 17:04:32.024 INFO 28712 --- [ main] com.o2xp.ats.accountManager.App : Starting App on frozzen-PC with PID 28712 (/home/frozzen/workspace/ATS/ats-parent/ats-impl/ats-accountManager/target/classes started by frozzen in /home/frozzen/workspace/ATS/ats-parent/ats-impl/ats-accountManager)
2017-06-26 17:04:32.030 INFO 28712 --- [ main] com.o2xp.ats.accountManager.App : No active profile set, falling back to default profiles: default
2017-06-26 17:04:32.282 INFO 28712 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#45f45fa1: startup date [Mon Jun 26 17:04:32 CEST 2017]; root of context hierarchy
2017-06-26 17:04:35.685 INFO 28712 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-06-26 17:04:35.723 INFO 28712 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2017-06-26 17:04:35.724 INFO 28712 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.14
2017-06-26 17:04:35.962 INFO 28712 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-06-26 17:04:35.962 INFO 28712 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3688 ms
2017-06-26 17:04:36.361 INFO 28712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-06-26 17:04:36.362 INFO 28712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-06-26 17:04:36.362 INFO 28712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-06-26 17:04:36.362 INFO 28712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-06-26 17:04:36.364 INFO 28712 --- [ost-startStop-1] .s.DelegatingFilterProxyRegistrationBean : Mapping filter: 'springSecurityFilterChain' to: [/*]
2017-06-26 17:04:36.365 INFO 28712 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-06-26 17:04:37.170 INFO 28712 --- [ main] j.LocalContainerEntityManagerFactoryBean : Building JPA container EntityManagerFactory for persistence unit 'default'
2017-06-26 17:04:37.195 INFO 28712 --- [ main] o.hibernate.jpa.internal.util.LogHelper : HHH000204: Processing PersistenceUnitInfo [
name: default
...]
2017-06-26 17:04:37.300 INFO 28712 --- [ main] org.hibernate.Version : HHH000412: Hibernate Core {5.0.12.Final}
2017-06-26 17:04:37.302 INFO 28712 --- [ main] org.hibernate.cfg.Environment : HHH000206: hibernate.properties not found
2017-06-26 17:04:37.305 INFO 28712 --- [ main] org.hibernate.cfg.Environment : HHH000021: Bytecode provider name : javassist
2017-06-26 17:04:37.373 INFO 28712 --- [ main] o.hibernate.annotations.common.Version : HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
2017-06-26 17:04:37.741 INFO 28712 --- [ main] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.H2Dialect
2017-06-26 17:04:38.642 INFO 28712 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000227: Running hbm2ddl schema export
2017-06-26 17:04:38.721 INFO 28712 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000230: Schema export complete
2017-06-26 17:04:38.767 INFO 28712 --- [ main] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
2017-06-26 17:04:39.857 INFO 28712 --- [ main] o.s.s.web.DefaultSecurityFilterChain : Creating filter chain: org.springframework.security.web.util.matcher.AnyRequestMatcher#1, [org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter#ff0e6d4, org.springframework.security.web.context.SecurityContextPersistenceFilter#1a785fd5, org.springframework.security.web.header.HeaderWriterFilter#1d1bf7bf, org.springframework.security.web.csrf.CsrfFilter#748904e8, org.springframework.security.web.authentication.logout.LogoutFilter#650a1aff, org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter#10bf1ec9, org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter#8f39224, org.springframework.security.web.authentication.www.BasicAuthenticationFilter#7606bd03, org.springframework.security.web.savedrequest.RequestCacheAwareFilter#362a561e, org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter#ad0bb4e, org.springframework.security.web.authentication.AnonymousAuthenticationFilter#70d3cdbf, org.springframework.security.web.session.SessionManagementFilter#4d43a1b7, org.springframework.security.web.access.ExceptionTranslationFilter#919086, org.springframework.security.web.access.intercept.FilterSecurityInterceptor#6b3f4bd8]
2017-06-26 17:04:40.221 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for #ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#45f45fa1: startup date [Mon Jun 26 17:04:32 CEST 2017]; root of context hierarchy
2017-06-26 17:04:40.323 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/registration],methods=[POST]}" onto public java.lang.String com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.registration(com.o2xp.ats.accountManager.to.ApplicantTO,org.springframework.validation.BindingResult,org.springframework.ui.Model)
2017-06-26 17:04:40.324 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/registration],methods=[GET]}" onto public java.lang.String com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.registration(org.springframework.ui.Model)
2017-06-26 17:04:40.325 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/categories],methods=[GET]}" onto public java.util.List<com.o2xp.ats.accountManager.to.ApplicantTO> com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.getAllApplicants()
2017-06-26 17:04:40.326 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/categories/{id}],methods=[GET]}" onto public org.springframework.http.ResponseEntity<com.o2xp.ats.accountManager.ti.ApplicantTI> com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.getApplicantById(java.lang.Long)
2017-06-26 17:04:40.326 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/login],methods=[GET]}" onto public java.lang.String com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.login(org.springframework.ui.Model,java.lang.String,java.lang.String)
2017-06-26 17:04:40.327 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/ || /welcome],methods=[GET]}" onto public java.lang.String com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.welcome(org.springframework.ui.Model)
2017-06-26 17:04:40.327 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/categories/{id}],methods=[DELETE]}" onto public org.springframework.http.ResponseEntity<java.lang.Void> com.o2xp.ats.accountManager.rest.controllers.ApplicantResource.deleteApplicant(java.lang.Long)
2017-06-26 17:04:40.333 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-06-26 17:04:40.334 INFO 28712 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-06-26 17:04:40.380 INFO 28712 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-26 17:04:40.380 INFO 28712 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-26 17:04:40.445 INFO 28712 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-26 17:04:40.821 INFO 28712 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-06-26 17:04:40.894 INFO 28712 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-06-26 17:04:40.901 INFO 28712 --- [ main] com.o2xp.ats.accountManager.App : Started App in 9.52 seconds (JVM running for 10.076)
and here is my App :
package com.o2xp.ats.accountManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
/**
* Hello world!
*
*/
#SpringBootApplication
#ComponentScan({ "com.o2xp.ats.common.domain", "com.o2xp.ats.common.services", "com.o2xp.ats.common.mapper",
"com.o2xp.ats.accountManager.services", "com.o2xp.ats.accountManager.mapper",
"com.o2xp.ats.accountManager.domain", "com.o2xp.ats.accountManager.rest.controllers",
"com.o2xp.ats.accountManager.validator" })
#EnableJpaRepositories({ "com.o2xp.ats.common.repository", "com.o2xp.ats.accountManager.repository" })
#EntityScan({ "com.o2xp.ats.common.domain", "com.o2xp.ats.accountManager.domain" })
#EnableWebSecurity
public class App extends org.springframework.boot.web.support.SpringBootServletInitializer {
private static final Logger log = LoggerFactory.getLogger(App.class);
public static void main(String[] args) {
SpringApplication.run(App.class);
}
i've seen
If you fine-tune your logging configuration, ensure that the
org.springframework.boot.autoconfigure.security category is set to log
INFO messages, otherwise the default password will not be printed.
into the spring doc but don't know where is the file to modify.

Set logging level at application.properties. Take a look 26.4 Log Levels
logging.level.org.springframework.boot.autoconfigure.security=INFO

You need to add the key and logging level to application.properties.
Have a look here

Spring Boot Application is starting up from a JUnit test but unable to access through URL

I have a JUnit Test that starts my spring boot appcliation (Application.java).
#RunWith(SpringRunner.class)
#SpringBootTest(classes = Application.class)
public class AppclaitionTest {
#Test
public void contextLoads(){
Application.main(new String[]{});
}
}
If I run the JUnit test, Application is successfully starting up, but not accessible through url
Application Logs:
2017-06-16 12:18:07.918 INFO 207028 --- [ main] com.chandu.test.AppclaitionTest : Started AppclaitionTest in 1.927 seconds (JVM running for 2.458)
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.5.3.RELEASE)
2017-06-16 12:18:08.012 INFO 207028 --- [ main] com.test.app.Application : Starting Application on IVL-WS39 with PID 207028 (started by Bhanuchandar.Challa in D:\Jars\SpringJDBCMySQL)
2017-06-16 12:18:08.012 INFO 207028 --- [ main] com.test.app.Application : No active profile set, falling back to default profiles: default
2017-06-16 12:18:08.012 INFO 207028 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#3f1ddac2: startup date [Fri Jun 16 12:18:08 IST 2017]; root of context hierarchy
2017-06-16 12:18:08.402 INFO 207028 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-06-16 12:18:08.417 INFO 207028 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2017-06-16 12:18:08.417 INFO 207028 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.14
2017-06-16 12:18:08.526 INFO 207028 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-06-16 12:18:08.526 INFO 207028 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 514 ms
2017-06-16 12:18:08.636 INFO 207028 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-06-16 12:18:08.636 INFO 207028 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-06-16 12:18:08.636 INFO 207028 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-06-16 12:18:08.636 INFO 207028 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-06-16 12:18:08.636 INFO 207028 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-06-16 12:18:08.933 INFO 207028 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for #ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#3f1ddac2: startup date [Fri Jun 16 12:18:08 IST 2017]; root of context hierarchy
2017-06-16 12:18:08.933 INFO 207028 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/getRowCount]}" onto public java.lang.Integer com.test.app.controller.TestController.getRowCount(java.lang.String)
2017-06-16 12:18:08.949 INFO 207028 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/process]}" onto public java.lang.String com.test.app.controller.TestController.processRequest()
2017-06-16 12:18:08.949 INFO 207028 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-06-16 12:18:08.949 INFO 207028 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-06-16 12:18:08.964 INFO 207028 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-16 12:18:08.964 INFO 207028 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-16 12:18:08.980 INFO 207028 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-16 12:18:09.105 INFO 207028 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-06-16 12:18:09.151 INFO 207028 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-06-16 12:18:09.151 INFO 207028 --- [ main] com.test.app.Application : Started Application in 1.186 seconds (JVM running for 3.689)
When I tried to access the application through url 'http://localhost:8080/process', It says Site can't be reached.

Why would you do such thing? This should be a unit test and the flow of the test should be the following:
Start the application -> Call your controller endpoint -> assert that a specific text/element on that page is present -> Shut down the application.
Start the application : #RunWith(SpringRunner.class) doing this for you, no need to start is manually.
Shut down the application : At the end of your test class Spring boot does this for you (That's why you cant access your app in the browser)
For further help please see my answer here: How to test (rest) enpoints

By default, in #SpringBootTest annotation the field webEnvironment is set to WebEnvironment.MOCK
Therefore, Tomcat does not start.
You can set this field to WebEnvironment.DEFINED_PORT/RANDOM_PORT.
After this, Tomcat will be running.
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
public class MyTestClass {
...
...
...
}

Spring Boot Getting Startet 404 error

I'm trying to use the spring framework for the first time. Unfortunately I'm getting 404-error when I call the URL of my webservice. Tomcat deployment of the war file is working (no errors in the logs).
When I execute the Example.java in eclipse everythings works fine.
Where is the mistake?
See my files/logs:
Example.java
import org.springframework.boot.*;
import org.springframework.boot.autoconfigure.*;
import org.springframework.stereotype.*;
import org.springframework.web.bind.annotation.*;
#Controller
#EnableAutoConfiguration
public class Example {
#RequestMapping("/")
#ResponseBody
String home() {
return "Hello World!";
}
public static void main(String[] args) throws Exception {
SpringApplication.run(Example.class, args);
}
}
build.gradle
buildscript {
repositories {
jcenter()
maven { url 'http://repo.spring.io/snapshot' }
maven { url 'http://repo.spring.io/milestone' }
}
dependencies {
classpath 'org.springframework.boot:spring-boot-gradle-plugin:2.0.0.BUILD-SNAPSHOT'
}
}
task wrapper(type: Wrapper) {
gradleVersion = '3.5'
}
apply plugin: 'java'
apply plugin: 'war'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'
jar {
baseName = 'myproject'
version = '0.0.1-SNAPSHOT'
}
repositories {
jcenter()
maven { url "http://repo.spring.io/snapshot" }
maven { url "http://repo.spring.io/milestone" }
}
dependencies {
//compile 'org.slf4j:slf4j-api:1.7.21'
compile("org.springframework.boot:spring-boot-starter-web")
testCompile("org.springframework.boot:spring-boot-starter-test")
//testCompile 'junit:junit:4.12'
}
log when starting the application inside eclipse
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.0.0.BUILD-SNAPSHOT)
2017-06-01 16:22:17.745 INFO 14940 --- [ main] Example : Starting Example on Laptop-Timo with PID 14940 (started by Timo in C:\Users\Timo\Documents\SE\Semester 4\LabSW\Webservice\TimeShoppingService)
2017-06-01 16:22:17.745 INFO 14940 --- [ main] Example : No active profile set, falling back to default profiles: default
2017-06-01 16:22:17.815 INFO 14940 --- [ main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext#6a01e23: startup date [Thu Jun 01 16:22:17 CEST 2017]; root of context hierarchy
2017-06-01 16:22:20.098 INFO 14940 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2017-06-01 16:22:20.116 INFO 14940 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2017-06-01 16:22:20.116 INFO 14940 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.15
2017-06-01 16:22:20.264 INFO 14940 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-06-01 16:22:20.264 INFO 14940 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2449 ms
2017-06-01 16:22:20.626 INFO 14940 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-06-01 16:22:20.638 INFO 14940 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-06-01 16:22:20.639 INFO 14940 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-06-01 16:22:20.639 INFO 14940 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-06-01 16:22:20.640 INFO 14940 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-06-01 16:22:21.343 INFO 14940 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for #ControllerAdvice: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext#6a01e23: startup date [Thu Jun 01 16:22:17 CEST 2017]; root of context hierarchy
2017-06-01 16:22:21.442 INFO 14940 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto java.lang.String Example.home()
2017-06-01 16:22:21.456 INFO 14940 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-06-01 16:22:21.457 INFO 14940 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-06-01 16:22:21.548 INFO 14940 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-01 16:22:21.549 INFO 14940 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-01 16:22:21.683 INFO 14940 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-06-01 16:22:21.940 INFO 14940 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-06-01 16:22:22.018 INFO 14940 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http)
2017-06-01 16:22:22.024 INFO 14940 --- [ main] Example : Started Example in 4.81 seconds (JVM running for 5.487)
2017-06-01 16:22:32.727 INFO 14940 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet 'dispatcherServlet'
2017-06-01 16:22:32.727 INFO 14940 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization started
2017-06-01 16:22:32.755 INFO 14940 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : FrameworkServlet 'dispatcherServlet': initialization completed in 28 ms

Use #RestController instead of #Controller and just give request like
localhost:8080/

In order to deploy a spring-boot application to an external servlet container you need to extend SpringBootServletInitializer.
The main method is only executed when the application is run standalone.
It is recommended to run spring-boot apps standalone rather than via an external servlet container, but it is possible to support both methods simultaneously.
See the spring documentation for more information.

By Default context path of Spring boot application is '/'. So in your case url to access home resource will be http://localhost:8080/
For custom context path add an application.properties file to src\main\resources. In that properties file, add 2 properties:
server.contextPath=/Service
server.port=12378
You may refer this link for example.

Maybe url mistake. try it like the url below .
http://localhost:8080/Service/

You have not mapped your controller or method with any specific string.
#Controller
#EnableAutoConfiguration
public class Example {
#RequestMapping("/")
#ResponseBody
String home() {
return "Hello World!";
}
...
You have used #RequestMapping("/") which maps the home() method so you need to use localhost:8080/ url instead of localhost:8080/service
and if you want to use the service in url just change mapping to #RequestMapping("/service").

The easiest way out is just by replacing the annotation above the class respectively. And use the #RestController, then you move the #RequestMapping("/") above the class, Beneath the rest controller. Go to the Postman and call it with localhost:8080/ and that's all

When Is My Business Code Actually Being Executed?

I got a Spring Boot app. It's running as such:
#SpringBootApplication
public class MyBooty implements CommandLineRunner {
public static void main(String[] args) {
SpringApplication.run(MyBooty.class, args);
}
public void run(String... args) throws Exception {
SomeClass someClass = new SomeClass(...);
someClass.doStuff();
System.out.println("Why Am I appearing Before \"Started In\" log line?");
}
Does what I need. But I noticed this line in the output: Started MyBooty in 17.594 seconds (JVM running for 18.206), which was printed after some of my console output.
This made me think my code was actually executing before the app was actually initialized. So I did some research found this blog post and then set up a new class as such:
#Component
public class ApplicationStartup implements ApplicationListener<ApplicationReadyEvent>{
public void onApplicationEvent(ApplicationReadyEvent event) {
SomeClass someClass = new SomeClass(...);
SomeClass.doStuff();
return;
}
}
Which supposedly executes after after application startup. Well, I still see the Started app in... output after my output again.
So, concept check. Are things working as intended and I'm just being naive? Or is there maybe something missing? If someone could knowledge share on the topic that would be appreciated.
Again, my code runs and does exactly what I need it to, but I just want to make sure I'm using/taking advantage of Spring Boot properly.
In case it's unclear what I'm asking, I'm asking Why does the "Started App in X seconds" message appear after my output? I ask this because I simply found it confusing that it said the app was started after my business code had ALREADY ran. This question is a conceptual question about how spring boot starts up.
Edit: Console Output
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.3.2.RELEASE)
2016-09-23 17:44:56.598 INFO 1004 --- [ main] o.b.p.MyBooty : Starting MyBooty on ********* with PID **** (C:\...\MyBooty)
:
:
:
2016-09-23 17:44:59.152 INFO 1004 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2016-09-23 17:44:59.154 INFO 1004 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.0.30
2016-09-23 17:44:59.725 INFO 1004 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2016-09-23 17:44:59.725 INFO 1004 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3074 ms
2016-09-23 17:45:00.228 INFO 1004 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2016-09-23 17:45:00.234 INFO 1004 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2016-09-23 17:45:00.234 INFO 1004 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2016-09-23 17:45:00.234 INFO 1004 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2016-09-23 17:45:00.234 INFO 1004 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2016-09-23 17:45:00.824 INFO 1004 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for #ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#453da22c: startup date [Fri Sep 23 17:44:56 CDT 2016]; root of context hierarchy
2016-09-23 17:45:00.901 INFO 1004 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2016-09-23 17:45:00.902 INFO 1004 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2016-09-23 17:45:00.925 INFO 1004 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-09-23 17:45:00.925 INFO 1004 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-09-23 17:45:00.962 INFO 1004 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2016-09-23 17:45:01.136 INFO 1004 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2016-09-23 17:45:01.215 INFO 1004 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
Why Am I appearing Before "Started In" log line?
2016-09-23 17:45:17.063 INFO 1004 --- [ main] o.b.p.MyBooty : Started MyBooty in 20.814 seconds (JVM running for 23.279) <----- Why is this after my output?
2016-09-23 17:45:22.675 INFO 1004 --- [)-10.168.50.106] inMXBeanRegistrar$SpringApplicationAdmin : Application shutdown requested.
2016-09-23 17:45:22.676 INFO 1004 --- [)-10.168.50.106] ationConfigEmbeddedWebApplicationContext : Closing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#453da22c: startup date [Fri Sep 23 17:44:56 CDT 2016]; root of context hierarchy
2016-09-23 17:45:22.678 INFO 1004 --- [)-10.168.50.106] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans on shutdown

You class is annotated with #SpringBootApplication, which makes it automatically register as a Spring Bean.
The SpringApplication run(Object source, String... args) method you are calling ends up calling run(String... args).
The run() method calls the afterRefresh() method right before it logs the "Started ..." message, and afterRefresh() will call the run() method of any registered ApplicationRunner and CommandLineRunner beans.
Or, as the documentation says it:
If you need to run some specific code once the SpringApplication has started, you can implement the ApplicationRunner or CommandLineRunner interfaces. Both interfaces work in the same way and offer a single run method which will be called just before SpringApplication.run(…​) completes.