[Demonstration 1]

[Buggy Method]
public List<Assignment> findByUserId(String userId) throws AssignmentAccessException {
    List<Assignment> assignments = assignmentRepository.findByUserId(new ObjectId(userId));
    if (assignments == null) {
        throw new AssignmentAccessException(AssignmentAccessException.NO_OBJECTS_BY_USER_ID_FOUND_TEXT_ID, new String[] { userId });
    }
    return filterByLoginUser(assignments);
}

[Buggy Hunk]
public List<Assignment> findByUserId(String userId) throws AssignmentAccessException {

[Patch]
public List<Assignment> findByUserId(String userId) throws AssignmentAccessException, UserAccessException {

[Demonstration 2]

[Buggy Method]
public boolean isRoleRequired(long userId, long organizationId, long roleId) throws PortalException, SystemException {
    List<UserGroupRole> userGroupRoles = new ArrayList<UserGroupRole>();
    Organization organization = OrganizationLocalServiceUtil.getOrganization(organizationId);
    UserGroupRolePK userGroupRolePK = new UserGroupRolePK(userId, organization.getGroupId(), roleId);
    UserGroupRole userGroupRole = UserGroupRoleLocalServiceUtil.getUserGroupRole(userGroupRolePK);
    userGroupRoles.add(userGroupRole);
    try {
        checkRoles(null, userGroupRoles);
    } catch (Exception e) {
        return true;
    }
    return false;
}

[Buggy Hunk]
UserGroupRoleLocalServiceUtil.getUserGroupRole(userGroupRolePK);

[Patch]
UserGroupRoleLocalServiceUtil.createUserGroupRole(userGroupRolePK);

[Demonstration 3]

[Buggy Method]
@Override
public List deleteItemUser(String id_user, Integer basket) {
    System.out.println("Delete Item in table basket!");
    jdbcTemplate.update(deleteQuery, new Object[] { id_user, basket });
    System.out.println(dataList.stream().filter(basket1 -> basket.equals(basket1.getId())));
    dataList.remove(dataList.stream().filter(basket1 -> basket.equals(basket1.getId())));
    System.out.println(dataList.isEmpty());
    return dataList;
}

[Buggy Hunk]
dataList.remove(dataList.stream().filter(basket1 -> basket.equals(basket1.getId())));

[Patch]
dataList.remove(dataList.stream().filter(basket1 -> basket.equals(basket1.getId())).findAny().orElse(null));