Last Modified 5.15.2025

Using Thymeleaf in WebFlux

https://github.com/kimjonghoon/webflux-thymeleaf

Run

mvn jetty:run

Visit http://localhost:8080

thymeleaf layout test screen

POM

<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>net.java_school.tutorial</groupId>
<artifactId>webflux-thymeleaf</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>WebFlux Thymeleaf</name>
<url>http://localhost:8080</url>

<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <maven.compiler.source>21</maven.compiler.source>
  <maven.compiler.target>21</maven.compiler.target>
  <spring.version>6.2.6</spring.version>
  <failOnMissingWebXml>false</failOnMissingWebXml>
</properties>

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-framework-bom</artifactId>
      <version>${spring.version}</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webflux</artifactId>
  </dependency>
  <!-- https://mvnrepository.com/artifact/org.thymeleaf/thymeleaf-spring6 -->
  <dependency>
    <groupId>org.thymeleaf</groupId>
    <artifactId>thymeleaf-spring6</artifactId>
    <version>3.1.3.RELEASE</version>
  </dependency>
  <!-- https://mvnrepository.com/artifact/jakarta.servlet/jakarta.servlet-api -->
  <dependency>
    <groupId>jakarta.servlet</groupId>
    <artifactId>jakarta.servlet-api</artifactId>
    <version>6.0.0</version>
    <scope>provided</scope>
  </dependency>
  <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
  <dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>2.1.0-alpha1</version>
  </dependency>
  <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
  <dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-classic</artifactId>
    <version>1.5.18</version>
    <scope>compile</scope>
  </dependency>
</dependencies>

<build>
  <finalName>webflux-thymeleaf</finalName>
  <pluginManagement>
    <plugins>
      <plugin>
        <artifactId>maven-clean-plugin</artifactId>
        <version>3.4.1</version>
      </plugin>
      <plugin>
        <artifactId>maven-resources-plugin</artifactId>
        <version>3.3.1</version>
      </plugin>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.14.0</version>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>3.5.3</version>
      </plugin>
      <plugin>
        <artifactId>maven-war-plugin</artifactId>
        <version>3.4.0</version>
      </plugin>
      <plugin>
        <artifactId>maven-install-plugin</artifactId>
        <version>3.1.4</version>
      </plugin>
      <plugin>
        <artifactId>maven-deploy-plugin</artifactId>
        <version>3.1.4</version>
      </plugin>
      <!-- https://mvnrepository.com/artifact/org.eclipse.jetty/jetty-maven-plugin -->
      <plugin>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-maven-plugin</artifactId>
        <version>11.0.25</version>
      </plugin>
    </plugins>
  </pluginManagement>
</build>
</project>

Java-based Configuration

package net.java_school.config;

import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.ResourceBundleMessageSource;
import org.springframework.web.reactive.config.EnableWebFlux;
import org.springframework.web.reactive.config.ResourceHandlerRegistry;
import org.springframework.web.reactive.config.ViewResolverRegistry;
import org.springframework.web.reactive.config.WebFluxConfigurer;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.annotation.Autowired;
import org.thymeleaf.spring6.ISpringWebFluxTemplateEngine;
import org.thymeleaf.spring6.SpringWebFluxTemplateEngine;
import org.thymeleaf.spring6.templateresolver.SpringResourceTemplateResolver;
import org.thymeleaf.spring6.view.reactive.ThymeleafReactiveViewResolver;
import org.thymeleaf.templatemode.TemplateMode;

@Configuration
@EnableWebFlux
@ComponentScan("net.java_school.blog")
public class AppConfig implements ApplicationContextAware, WebFluxConfigurer {

  @Autowired
  private ApplicationContext applicationContext;

  @Override
  public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
    this.applicationContext = applicationContext;
  }

  @Override
  public void addResourceHandlers(final ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/static/**").addResourceLocations("classpath:static/");
  }

  @Bean
  public ResourceBundleMessageSource messageSource() {
    ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
    messageSource.setBasename("classpath:messages");
    messageSource.setDefaultEncoding("UTF-8");
    return messageSource;
  }

  @Bean
  public SpringResourceTemplateResolver templateResolver() {
    final SpringResourceTemplateResolver resolver = new SpringResourceTemplateResolver();
    resolver.setApplicationContext(this.applicationContext);
    resolver.setPrefix("classpath:templates/");
    resolver.setSuffix(".html");
    resolver.setTemplateMode(TemplateMode.HTML);
    resolver.setCacheable(false);
    return resolver;
  }

  @Bean
  public ISpringWebFluxTemplateEngine templateEngine() {
    SpringWebFluxTemplateEngine templateEngine = new SpringWebFluxTemplateEngine();
    templateEngine.setTemplateResolver(templateResolver());
    templateEngine.setEnableSpringELCompiler(true);
    return templateEngine;
  }

  @Bean
  public ThymeleafReactiveViewResolver viewResolver() {
    ThymeleafReactiveViewResolver viewResolver = new ThymeleafReactiveViewResolver();
    viewResolver.setTemplateEngine(templateEngine());
    viewResolver.setResponseMaxChunkSizeBytes(16348);
    return viewResolver;
  }

  @Override public void configureViewResolvers(ViewResolverRegistry registry) {
    registry.viewResolver(this.viewResolver());
  }
}

package net.java_school.config;

import org.springframework.web.server.adapter.AbstractReactiveWebInitializer;

public class MyWebApplicationInitializer extends AbstractReactiveWebInitializer {

  @Override
  protected Class<?>[] getConfigClasses() {
    return new Class<?>[] {AppConfig.class};
  }
}

Controller

package net.java_school.blog;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

@Controller
public class MyController {

  @GetMapping("/")
  public String index() {
    return "index";
  }
	
  @GetMapping(value={"{chapter:java|jdbc|jsp|css-layout|jsp-pjt|spring|javascript|google-cloud}", 
      "{chapter:java|jdbc|jsp|css-layout|jsp-pjt|spring|javascript|google-cloud}/{lecture}"})
  public String lecture(@PathVariable("chapter") String chapter, 
      @PathVariable(value="lecture", required=false) String lecture) {

    if (lecture != null) {
      return chapter + "/" + lecture;
    } else {
      return chapter + "/index";	
    }
  }
	
  @GetMapping("blog")
  public String getBlogHome() {
    return "blog/index";
  }
  
  @GetMapping("blog/{year:\\d+}/{post}")
  public String getPost(@PathVariable("year") year, @PathVariable("post") post) {
    return "blog/" + year + "/" + post;  		
  }
}

References

https://hantsy.github.io/spring-reactive-sample/start/first.html