WebConfig.java

package com.captechconsulting.config;

import com.fasterxml.jackson.annotation.JsonInclude;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.validation.Validator;
import org.springframework.validation.beanvalidation.LocalValidatorFactoryBean;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import java.util.List;

@Configuration
@EnableWebMvc
public class WebConfig extends WebMvcConfigurerAdapter {

    @Autowired
    private MessageSource messageSource;

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        converter.getObjectMapper().setSerializationInclusion(JsonInclude.Include.NON_NULL);
        converters.add(converter);
    }

    @Bean
    public LocalValidatorFactoryBean validator() {
        LocalValidatorFactoryBean validatorFactoryBean = new LocalValidatorFactoryBean();
        validatorFactoryBean.setValidationMessageSource(messageSource);
        return validatorFactoryBean;
    }

    @Override
    public Validator getValidator() {
        return validator();
    }
}