wffweb/src/main/java/com/webfirmframework/wffweb/tag/repository/TagRepository.java
public Collection<AbstractAttribute> findAttributesByAttributeFilter(
            final boolean parallel,
            final Predicate<? super AbstractAttribute> filter)
            throws NullValueException {

        if (filter == null) {
            throw new NullValueException("The filter should not be null");
        }

        final Collection<Lock> locks = getReadLocks(rootTags);
        for (final Lock lock : locks) {
            lock.lock();
        }

        try {
            final Stream<AbstractAttribute> attributesStream = buildAllTagsStream(
                    parallel).filter(tag -> tag.getAttributes() != null)
                            .map(tag -> {
                                return tag.getAttributes();
                            }).flatMap(attributes -> attributes.stream());

            return attributesStream.filter(filter).collect(Collectors.toSet());
        } finally {
            for (final Lock lock : locks) {
                lock.unlock();
            }

        }
    }
public Collection<AbstractAttribute> findAttributesByAttributeFilter(
            final boolean parallel,
            final Predicate<? super AbstractAttribute> filter)
            throws NullValueException {

        if (filter == null) {
            throw new NullValueException("The filter should not be null");
        }

        final Collection<Lock> locks = getReadLocks(rootTags);
        for (final Lock lock : locks) {
            lock.lock();
        }

        try {
            final Stream<AbstractAttribute> attributesStream = buildAllTagsStream(
                    parallel).filter(tag -> tag.getAttributes() != null)
                            .map(tag -> {
                                return tag.getAttributes();
                            }).flatMap(attributes -> attributes.stream());

            return attributesStream.filter(filter).collect(Collectors.toSet());
        } finally {
            for (final Lock lock : locks) {
                lock.unlock();
            }

        }
    }
Finds and returns the collection of attributes (including from nested
tags) of the tags filtered by the given filter

@param parallel
true to internally use parallel stream. If true it
will split the finding task to different batches and
will execute the batches in different threads in
parallel consuming all CPUs. It will perform faster
in finding from extremely large number of tags but at
the same time it will less efficient in finding from
small number of tags.
@param filter
the filter lambda expression containing return true
to include and false to exclude.
@return the collection of attributes by the given filter.
@throws NullValueException
if the {@code tagName} is null
@since 3.0.0
@author WFF