Map a file (for example, a JSON) into an object with a few lines of code in Spring Boot.

SpringBootFileToObjectMapper.java

import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.*;
import org.springframework.util.ResourceUtils;
import java.io.IOException;

public class FileLoaderExample {
    public static <DTO> DTO getDto(String path, Class<DTO> clazz) {
        DTO dto = null;

        try {
            dto = new ObjectMapper().readValue(ResourceUtils.getFile(path),
                    clazz);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return dto;
    }
    
    /* 
    // Inefficient way to use getDTO function to get the json content
    // in String format. 
    
    public static final ObjectWriter objectMapper = new ObjectMapper()
            .configure(SerializationFeature.WRAP_ROOT_VALUE, false)
            .writer().withDefaultPrettyPrinter();
    
    public static String jsonToString(String jsonRoute, Class clazz) {
        try {
            return objectMapper.writeValueAsString(
                    getDto(jsonRoute, clazz));
        } catch (JsonProcessingException e) {
            return "invalid json";
        }
    }
     */
}