Parameter 0 of constructor in required a bean of type 'java.lang.String' that could not be found

Since you do not provide the public default constructor and you added your own non-default constructor the instantiation will fail. I would suggest you to define the input file path as property like @Value("${inputFilePath}"). If you need further initialization in your bean define a void method and annotate it with @PostConstruct and do the initialization within.

Add a public default constructor in your class. For example.

public User() {
}

Make sure you are using spring-boot-starter-data-jpa

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>