Hibernate Attribute Converter Integer and String

Question

I have int id of primary key in the hibernate entity and in the DTO object, I have same int id and String encId for encrypted primary key id. Every time when I transfer the entity to DTO using BeanUtils.copyProperties() to copy entity to DTO vise versa, in the next line I'm encrypt/decrypting and performing db operation.

Could you please help me how to use AttributeConverter<Integer, String> and to copy the bean I should only do BeanUtils.copyProperties() and no more enc/decrypt logic other than AttributeConverter. Please give me the sample snipet of Entity to DTO.

Answer 1

entity:

@Entity
public class Book {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
  
    @Convert(converter = IntegerToStringConverter.class)
    private Integer span;
}

converter

@Converter
public class IntegerToStringConverter
    implements AttributeConverter<Integer, String> {

     @Override
     public String convertToDatabaseColumn(Integer value) {
        
          try {
              return Integer.toString(number);
          } else {
              throw new IllegalStateException(
                     "Invalid number: " + value
              );
          }
     }
 
     @Override
     public Integer convertToEntityAttribute(String number) {

         try {
             return Integer.parseInt(number);   
         } catch(Exception e) {
             throw new IllegalStateException(
                 "Invalid number: " + value
             );
         }
     }

}

here is a running example