DropImpl extends BaseSqlPart implements Drop { @Nullable @Override public SqlPart previous() { return null; }  @NotNull @Override DropTable table(@NotNull final String tableName); @NotNull @Override DropTable table(@Nullable final String databaseName, @NotNull final String tableName); @NotNull @Override DropTableIfExists tableIfExists(@NotNull final String tableName); @NotNull @Override DropTableIfExists tableIfExists(@Nullable final String databaseName, @NotNull final String tableName); @Override void prependTo(@NotNull final RawSqlBuilder builder); @Nullable @Override SqlPart previous();  }
@Test public void previous_returnsNullValue() { DropImpl drop = new DropImpl(); SqlPart result = drop.previous(); assertThat(result, is(nullValue())); }