TL;DR: I have a Spring MVC Hello, World! application that works on Tomcat 9. The same application on Tomcat 10 gives a 404 error for web request mappings.
The Problem
When deploying a Spring MVC 5 Hello, World! application to Tomcat 10, the application gives a 404 error for web request mappings. The same Hello, World! application works on Tomcat 9. It displays the Hello, World! message on Tomcat 9.
What I Expected
I expected the application to display the Hello, World! message on Tomcat 10.
Environment
- MS Windows 10
- Tomcat 10.0.2
- Spring MVC 5.3.3
Research I Performed
I researched in the Spring Reference Manual, Section on Web Servlet. I also tested Spring MVC Tutorials online. These tutorials worked on Tomcat 9. However, the same tutorials failed on Tomcat 10. I also performed Google search on Tomcat 10. I saw references to Jakarta EE, but I am not sure if this is the source of the issue. Java EE 8 and Jakarta EE 8 are backwards compatible.
How to Reproduce
I created a very basic Hello, World! project to test this out. Here is the code that I'm using for the project.
File 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.example.spring</groupId>
<artifactId>example-spring</artifactId>
<version>1.0</version>
<packaging>war</packaging>
<properties>
<maven.compiler.target>11</maven.compiler.target>
<maven.compiler.source>11</maven.compiler.source>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.3.3</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>3.3.1</version>
</plugin>
</plugins>
</build>
</project>
File ProjectInitializer.java
package com.example;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
public class ProjectInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected Class<?>[] getServletConfigClasses() {
return new Class[] { PureJavaConfig.class };
}
@Override
protected String[] getServletMappings() {
return new String[] { "/" };
}
@Override
protected Class<?>[] getRootConfigClasses() {
return null;
}
}
File PureJavaConfig.java
package com.example;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
@Configuration
@EnableWebMvc
@ComponentScan("com.example")
public class PureJavaConfig {
@Bean
public ViewResolver viewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setSuffix(".jsp");
resolver.setPrefix("/WEB-INF/jsp/");
return resolver;
}
}
File TutorialController.java
package com.example;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class TutorialController {
@GetMapping("/")
public String home() {
return "home";
}
}
File home.jsp
<html>
<body>Hello, World! of Spring! <%= java.time.LocalDateTime.now() %></body>
</html>
This project runs okay on Tomcat 9. It displays the Hello, World! message. However, when I run on Tomcat 10, I get a 404 error message.