Examples with FilteringIterator io.requery.util.FilteringIterator used on opensource projects

Example 1 with FilteringIterator

use of io.requery.util.FilteringIterator in project requery by requery.

the class EntityReader method refresh.

private E refresh(E entity, EntityProxy<E> proxy, final Set<Attribute<E, ?>> attributes) {
    Predicate<Attribute<E, ?>> basicFilter = new Predicate<Attribute<E, ?>>() {

        @Override
        public boolean test(Attribute<E, ?> value) {
            return attributes.contains(value) && (!value.isAssociation() || value.isForeignKey());
        }
    };
    FilteringIterator<Attribute<E, ?>> filterator = new FilteringIterator<>(attributes.iterator(), basicFilter);
    if (filterator.hasNext()) {
        QueryBuilder qb = new QueryBuilder(context.getQueryBuilderOptions()).keyword(SELECT).commaSeparated(filterator, new QueryBuilder.Appender<Attribute<E, ?>>() {

            @Override
            public void append(QueryBuilder qb, Attribute<E, ?> value) {
                String versionColumn = context.getPlatform().versionColumnDefinition().columnName();
                if (value.isVersion() && versionColumn != null) {
                    qb.append(versionColumn).space().append(AS).space().append(value.getName()).space();
                } else {
                    qb.attribute(value);
                }
            }
        }).keyword(FROM).tableName(type.getName()).keyword(WHERE).appendWhereConditions(type.getKeyAttributes());
        String sql = qb.toString();
        try (Connection connection = context.getConnection();
            PreparedStatement statement = connection.prepareStatement(sql)) {
            int index = 1;
            for (Attribute<E, ?> attribute : type.getKeyAttributes()) {
                Object value = proxy.getKey(attribute);
                if (value == null) {
                    throw new MissingKeyException(proxy);
                }
                mapping.write((Expression) attribute, statement, index++, value);
            }
            context.getStatementListener().beforeExecuteQuery(statement, sql, null);
            ResultSet results = statement.executeQuery();
            context.getStatementListener().afterExecuteQuery(statement);
            if (results.next()) {
                Attribute[] selection = new Attribute[attributes.size()];
                attributes.toArray(selection);
                // modify the given entity
                if (type.isImmutable()) {
                    entity = fromBuilder(results, selection);
                } else {
                    entity = fromResult(entity, results, selection);
                }
            }
        } catch (SQLException e) {
            throw new PersistenceException(e);
        }
    }
    // refresh associations
    for (Attribute<E, ?> attribute : attributes) {
        // if it's a foreign key its resolved as part of the basic properties
        if (attribute.isAssociation()) {
            refreshAssociation(proxy, attribute);
        }
    }
    return entity;
}

Example 2 with FilteringIterator

use of io.requery.util.FilteringIterator in project requery by requery.

the class ModifiableResult method iterator.

@Override
public CloseableIterator<E> iterator() {
    // iterator that combines query results with not added elements and filtering out
    // removed elements
    final Iterator<E> queried = result == null ? Collections.<E>emptyIterator() : result.iterator();
    final Iterator<E> added = changes.addedElements().iterator();
    final Iterator<E> composite = new CompositeIterator<>(queried, added);
    final Iterator<E> filtered = new FilteringIterator<>(composite, new Predicate<E>() {

        @Override
        public boolean test(E e) {
            return !changes.removedElements().contains(e);
        }
    });
    return new CloseableIterator<E>() {

        @Override
        public void close() {
            if (queried instanceof CloseableIterator) {
                CloseableIterator closeable = (CloseableIterator) queried;
                closeable.close();
            }
        }

        @Override
        public boolean hasNext() {
            return filtered.hasNext();
        }

        @Override
        public E next() {
            return filtered.next();
        }

        @Override
        public void remove() {
            throw new UnsupportedOperationException();
        }
    };
}