Spring JPA之save方法示例详解

@Transactional
@Override
public <S extends T> S save(S entity) {
   Assert.notNull(entity, "Entity must not be null.");
   if (entityInformation.isNew(entity)) {
      em.persist(entity);
      return entity;
   } else {
      return em.merge(entity);
   }
}

/**
 * Must be {@link Transient} in order to ensure that no JPA provider complains because of a missing setter.
 *
 * @see org.springframework.data.domain.Persistable#isNew()
 */
@Transient // DATAJPA-622
@Override
public boolean isNew() {
   return null == getId();
}

@Transactional
public User save(User user) {
    return userDao.save(user);
}

/**
 * 单条数据保存
 * @param id 自增的，可以不填
 * @param name
 * @param age
 * @return
 */
@GetMapping("/save")
public User save(Integer id,String name, Integer age){
	User user = new User();
	user.setId(id);
	user.setName(name);
	user.setAge(age);
	return userService.save(user);
}

/*
 * (non-Javadoc)
 * @see org.springframework.data.jpa.repository.JpaRepository#save(java.lang.Iterable)
 */
@Transactional
@Override
public <S extends T> List<S> saveAll(Iterable<S> entities) {
   Assert.notNull(entities, "Entities must not be null!");
   List<S> result = new ArrayList<>();
   for (S entity : entities) {
      result.add(save(entity));
   }
   return result;
}

@Transactional
public <S extends User> List<S> saveAll(Iterable<S> entities) {
	return userDao.saveAll(entities);
}

/**
 * 批量保存数据
 * @param ids 
 * @param names
 * @param ages
 * @return
 */
@GetMapping("/saveAll")
public List<User> saveAll(int[] ids,String[] names,Integer[] ages){
    List<User> list = new ArrayList<>();
    for(int i=0; i<names.length; i++){
        User user = new User();
        user.setId(ids[i]);
        user.setName(names[i]);
        user.setAge(ages[i]);
        list.add(user);
    }
    return userService.saveAll(list);
}