spring-boot-rest/spring-web-modules/spring-mvc-basics-4/src/main/java/com/baeldung/config/WebConfig.java

package com.baeldung.config;

import org.springframework.boot.web.server.WebServerFactoryCustomizer;
import org.springframework.boot.web.servlet.server.ConfigurableServletWebServerFactory;
import org.springframework.context.annotation.Bean;
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;
import org.springframework.web.servlet.view.JstlView;
import org.thymeleaf.spring5.SpringTemplateEngine;
import org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver;
import org.thymeleaf.spring5.view.ThymeleafViewResolver;
import org.thymeleaf.templatemode.TemplateMode;
import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
import org.thymeleaf.templateresolver.ITemplateResolver;

import com.baeldung.contexts.Greeting;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Web Configuration for the entire app
 */
@Configuration
@EnableWebMvc
public class WebConfig {

    @Bean
    public WebServerFactoryCustomizer<ConfigurableServletWebServerFactory> enableDefaultServlet() {
        return factory -> factory.setRegisterDefaultServlet(true);
    }

    @Bean
    public Greeting greeting() {
        Greeting greeting = new Greeting();
        greeting.setMessage("Hello World !!");
        return greeting;
    }

    @Bean
    public ObjectMapper objectMapper() {
        return new ObjectMapper();
    }

    // Thymeleaf configuration
    @Bean
    public ViewResolver thymeleafViewResolver() {

        ThymeleafViewResolver viewResolver = new ThymeleafViewResolver();

        viewResolver.setTemplateEngine(thymeleafTemplateEngine());
        viewResolver.setCharacterEncoding("UTF-8");
        viewResolver.setOrder(0);

        return viewResolver;
    }

    // Thymeleaf template engine with Spring integration
    @Bean
    public SpringTemplateEngine thymeleafTemplateEngine() {

        SpringTemplateEngine templateEngine = new SpringTemplateEngine();
        templateEngine.setTemplateResolver(thymeleafTemplateResolver());
        templateEngine.setEnableSpringELCompiler(true);

        return templateEngine;
    }

    @Bean
    public SpringResourceTemplateResolver springResourceTemplateResolver() {
        return new SpringResourceTemplateResolver();
    }

    @Bean
    public ITemplateResolver thymeleafTemplateResolver() {

        ClassLoaderTemplateResolver templateResolver = new ClassLoaderTemplateResolver();

        templateResolver.setPrefix("/templates/");
        templateResolver.setCacheable(false);
        templateResolver.setSuffix(".html");
        templateResolver.setTemplateMode(TemplateMode.HTML);
        templateResolver.setCharacterEncoding("UTF-8");

        return templateResolver;
    }
}