com.sss.model.service

Class AnswersService

java.lang.Object

com.sss.model.service.AnswersService

All Implemented Interfaces:

IAnswersService

@Service
public class AnswersService
extends java.lang.Object
implements IAnswersService

Service class. Implementation of interface between presentation and model layer to perform operations on answers. Uses member variables that implements IAnswersRepository and ICommentablesRepository interfaces

Constructor Summary

Constructors

Constructor and Description
AnswersService()

Method Summary

Modifier and Type	Method and Description
AnswerBO	add(AnswerVO answerVO, java.lang.Long questionId) This method adds a new answer to a specified by id question.
void	delete(java.lang.Long questionId, java.lang.Long answerId) This method deletes a specified by id answer to a specified by id question.
java.util.List<AnswerBO>	findByQuestionId(java.lang.Long questionId) This method returns all answers that are available to a specified by id question.
AnswerBO	update(AnswerVO answerVO, java.lang.Long questionId, java.lang.Long answerId) This method updates an existing specified by id answer to a specified by id question.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AnswersService

public AnswersService()

Method Detail

findByQuestionId

public java.util.List<AnswerBO> findByQuestionId(java.lang.Long questionId)

This method returns all answers that are available to a specified by id question. It propagates request to data layer using IAnswersRepository method findByQuestionId. Then it wraps up each Answer instance into AnswerBO and collect them to List.

Specified by:

findByQuestionId in interface IAnswersService

Parameters:

questionId - Id of question to receive answers to

Returns:

List of AnswerBO's instances

add

public AnswerBO add(AnswerVO answerVO,
                    java.lang.Long questionId)

This method adds a new answer to a specified by id question. It first creates an Answer instance using vo2entity. Then it propagates request to data layer using IAnswersRepository method save. Returned from save Answer instance is wrapped into AnswerBO.

Specified by:

add in interface IAnswersService

Parameters:

answerVO - AnswerVO's instance with user's input data

questionId - Id of question to add an answer to

Returns:

AnswerBO's instance for a new created record

update

public AnswerBO update(AnswerVO answerVO,
                       java.lang.Long questionId,
                       java.lang.Long answerId)

This method updates an existing specified by id answer to a specified by id question. It first creates an Answer instance using vo2entity. Then it propagates request to data layer using IAnswersRepository method save. Returned from save Answer instance is wrapped into AnswerBO.

Specified by:

update in interface IAnswersService

Parameters:

answerVO - AnswerVO's instance with user's changed and old data.

questionId - Id of question to edit an answer to

answerId - Id of answer to edit

Returns:

AnswerBO's instance for an edited record

delete

@Transactional
public void delete(java.lang.Long questionId,
                                  java.lang.Long answerId)

This method deletes a specified by id answer to a specified by id question. It propagates request to data layer using IAnswersRepository and ICommentablesRepository methods delete. To realize cascade rule for relation between Commentable and Answer entity it first calls delete using a record with answerId in IAnswersRepository and then calls same method in ICommentablesRepository.

Specified by:

delete in interface IAnswersService

Parameters:

questionId - Id of question to delete an answer to

answerId - Id of answer to delete