+++ /dev/null
-/*
- * Sone - IdentityChangeDetector.java - Copyright © 2013–2019 David Roden
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-package net.pterodactylus.sone.freenet.wot;
-
-import static com.google.common.base.Optional.absent;
-import static com.google.common.base.Optional.fromNullable;
-import static com.google.common.base.Predicates.not;
-import static com.google.common.collect.FluentIterable.from;
-import static net.pterodactylus.sone.freenet.wot.Identity.TO_CONTEXTS;
-import static net.pterodactylus.sone.freenet.wot.Identity.TO_PROPERTIES;
-
-import java.util.Collection;
-import java.util.Map;
-import java.util.Map.Entry;
-
-import com.google.common.base.Optional;
-import com.google.common.base.Predicate;
-import com.google.common.collect.FluentIterable;
-import com.google.common.collect.ImmutableMap;
-
-/**
- * Detects changes between two lists of {@link Identity}s. The detector can find
- * added and removed identities, and for identities that exist in both list
- * their contexts and properties are checked for added, removed, or (in case of
- * properties) changed values.
- */
-public class IdentityChangeDetector {
-
- private final Map<String, Identity> oldIdentities;
- private Optional<IdentityProcessor> onNewIdentity = absent();
- private Optional<IdentityProcessor> onRemovedIdentity = absent();
- private Optional<IdentityProcessor> onChangedIdentity = absent();
- private Optional<IdentityProcessor> onUnchangedIdentity = absent();
-
- public IdentityChangeDetector(Collection<? extends Identity> oldIdentities) {
- this.oldIdentities = convertToMap(oldIdentities);
- }
-
- public void onNewIdentity(IdentityProcessor onNewIdentity) {
- this.onNewIdentity = fromNullable(onNewIdentity);
- }
-
- public void onRemovedIdentity(IdentityProcessor onRemovedIdentity) {
- this.onRemovedIdentity = fromNullable(onRemovedIdentity);
- }
-
- public void onChangedIdentity(IdentityProcessor onChangedIdentity) {
- this.onChangedIdentity = fromNullable(onChangedIdentity);
- }
-
- public void onUnchangedIdentity(IdentityProcessor onUnchangedIdentity) {
- this.onUnchangedIdentity = fromNullable(onUnchangedIdentity);
- }
-
- public void detectChanges(final Collection<? extends Identity> newIdentities) {
- notifyForRemovedIdentities(from(oldIdentities.values()).filter(notContainedIn(newIdentities)));
- notifyForNewIdentities(from(newIdentities).filter(notContainedIn(oldIdentities.values())));
- notifyForChangedIdentities(from(newIdentities).filter(containedIn(oldIdentities)).filter(hasChanged(oldIdentities)));
- notifyForUnchangedIdentities(from(newIdentities).filter(containedIn(oldIdentities)).filter(not(hasChanged(oldIdentities))));
- }
-
- private void notifyForRemovedIdentities(Iterable<Identity> identities) {
- notify(onRemovedIdentity, identities);
- }
-
- private void notifyForNewIdentities(FluentIterable<? extends Identity> newIdentities) {
- notify(onNewIdentity, newIdentities);
- }
-
- private void notifyForChangedIdentities(FluentIterable<? extends Identity> identities) {
- notify(onChangedIdentity, identities);
- }
-
- private void notifyForUnchangedIdentities(FluentIterable<? extends Identity> identities) {
- notify(onUnchangedIdentity, identities);
- }
-
- private void notify(Optional<IdentityProcessor> identityProcessor, Iterable<? extends Identity> identities) {
- if (!identityProcessor.isPresent()) {
- return;
- }
- for (Identity identity : identities) {
- identityProcessor.get().processIdentity(identity);
- }
- }
-
- private static Predicate<Identity> hasChanged(final Map<String, Identity> oldIdentities) {
- return new Predicate<Identity>() {
- @Override
- public boolean apply(Identity identity) {
- return (identity != null) && identityHasChanged(oldIdentities.get(identity.getId()), identity);
- }
- };
- }
-
- private static boolean identityHasChanged(Identity oldIdentity, Identity newIdentity) {
- return identityHasNewContexts(oldIdentity, newIdentity)
- || identityHasRemovedContexts(oldIdentity, newIdentity)
- || identityHasNewProperties(oldIdentity, newIdentity)
- || identityHasRemovedProperties(oldIdentity, newIdentity)
- || identityHasChangedProperties(oldIdentity, newIdentity);
- }
-
- private static boolean identityHasNewContexts(Identity oldIdentity, Identity newIdentity) {
- return from(TO_CONTEXTS.apply(newIdentity)).anyMatch(notAContextOf(oldIdentity));
- }
-
- private static boolean identityHasRemovedContexts(Identity oldIdentity, Identity newIdentity) {
- return from(TO_CONTEXTS.apply(oldIdentity)).anyMatch(notAContextOf(newIdentity));
- }
-
- private static boolean identityHasNewProperties(Identity oldIdentity, Identity newIdentity) {
- return from(TO_PROPERTIES.apply(newIdentity).entrySet()).anyMatch(notAPropertyOf(oldIdentity));
- }
-
- private static boolean identityHasRemovedProperties(Identity oldIdentity, Identity newIdentity) {
- return from(TO_PROPERTIES.apply(oldIdentity).entrySet()).anyMatch(notAPropertyOf(newIdentity));
- }
-
- private static boolean identityHasChangedProperties(Identity oldIdentity, Identity newIdentity) {
- return from(TO_PROPERTIES.apply(oldIdentity).entrySet()).anyMatch(hasADifferentValueThanIn(newIdentity));
- }
-
- private static Predicate<Identity> containedIn(final Map<String, Identity> identities) {
- return new Predicate<Identity>() {
- @Override
- public boolean apply(Identity identity) {
- return (identity != null) && identities.containsKey(identity.getId());
- }
- };
- }
-
- private static Predicate<String> notAContextOf(final Identity identity) {
- return new Predicate<String>() {
- @Override
- public boolean apply(String context) {
- return (identity != null) && !identity.getContexts().contains(context);
- }
- };
- }
-
- private static Predicate<Identity> notContainedIn(final Collection<? extends Identity> newIdentities) {
- return new Predicate<Identity>() {
- @Override
- public boolean apply(Identity identity) {
- return (identity != null) && !newIdentities.contains(identity);
- }
- };
- }
-
- private static Predicate<Entry<String, String>> notAPropertyOf(final Identity identity) {
- return new Predicate<Entry<String, String>>() {
- @Override
- public boolean apply(Entry<String, String> property) {
- return (property != null) && !identity.getProperties().containsKey(property.getKey());
- }
- };
- }
-
- private static Predicate<Entry<String, String>> hasADifferentValueThanIn(final Identity newIdentity) {
- return new Predicate<Entry<String, String>>() {
- @Override
- public boolean apply(Entry<String, String> property) {
- return (property != null) && !newIdentity.getProperty(property.getKey()).equals(property.getValue());
- }
- };
- }
-
- private static Map<String, Identity> convertToMap(Collection<? extends Identity> identities) {
- ImmutableMap.Builder<String, Identity> mapBuilder = ImmutableMap.builder();
- for (Identity identity : identities) {
- mapBuilder.put(identity.getId(), identity);
- }
- return mapBuilder.build();
- }
-
- public interface IdentityProcessor {
-
- void processIdentity(Identity identity);
-
- }
-
-}
projects / Sone.git / blobdiff