--- /dev/null
+/*
+ * Sone - IdentityChangeDetector.java - Copyright © 2013 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.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+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) ? false : 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)).anyMatch(notAPropertyOf(oldIdentity));
+ }
+
+ private static boolean identityHasRemovedProperties(Identity oldIdentity, Identity newIdentity) {
+ return from(TO_PROPERTIES.apply(oldIdentity)).anyMatch(notAPropertyOf(newIdentity));
+ }
+
+ private static boolean identityHasChangedProperties(Identity oldIdentity, Identity newIdentity) {
+ return from(TO_PROPERTIES.apply(oldIdentity)).anyMatch(hasADifferentValueThanIn(newIdentity));
+ }
+
+ private static Predicate<Identity> containedIn(final Map<String, Identity> identities) {
+ return new Predicate<Identity>() {
+ @Override
+ public boolean apply(Identity identity) {
+ return 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) ? false : !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) ? false : !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) ? false : !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) ? false : !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);
+
+ }
+
+}
--- /dev/null
+/*
+ * Sone - IdentityChangeDetectorTest.java - Copyright © 2013 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.collect.Lists.newArrayList;
+import static java.util.Arrays.asList;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.empty;
+
+import java.util.Collection;
+import java.util.Map;
+
+import net.pterodactylus.sone.freenet.wot.IdentityChangeDetector.IdentityProcessor;
+
+import com.google.common.collect.ImmutableMap;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit test for {@link IdentityChangeDetector}.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class IdentityChangeDetectorTest {
+
+ private final IdentityChangeDetector identityChangeDetector = new IdentityChangeDetector(createOldIdentities());
+ private final Collection<Identity> newIdentities = newArrayList();
+ private final Collection<Identity> removedIdentities = newArrayList();
+ private final Collection<Identity> changedIdentities = newArrayList();
+ private final Collection<Identity> unchangedIdentities = newArrayList();
+
+ @Before
+ public void setup() {
+ identityChangeDetector.onNewIdentity(new IdentityProcessor() {
+ @Override
+ public void processIdentity(Identity identity) {
+ newIdentities.add(identity);
+ }
+ });
+ identityChangeDetector.onRemovedIdentity(new IdentityProcessor() {
+ @Override
+ public void processIdentity(Identity identity) {
+ removedIdentities.add(identity);
+ }
+ });
+ identityChangeDetector.onChangedIdentity(new IdentityProcessor() {
+ @Override
+ public void processIdentity(Identity identity) {
+ changedIdentities.add(identity);
+ }
+ });
+ identityChangeDetector.onUnchangedIdentity(new IdentityProcessor() {
+ @Override
+ public void processIdentity(Identity identity) {
+ unchangedIdentities.add(identity);
+ }
+ });
+ }
+
+ @Test
+ public void noDifferencesAreDetectedWhenSendingTheOldIdentitiesAgain() {
+ identityChangeDetector.detectChanges(createOldIdentities());
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, empty());
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity2(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAnIdentityWasRemoved() {
+ identityChangeDetector.detectChanges(asList(createIdentity1(), createIdentity3()));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, containsInAnyOrder(createIdentity2()));
+ assertThat(changedIdentities, empty());
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAnIdentityWasAdded() {
+ identityChangeDetector.detectChanges(asList(createIdentity1(), createIdentity2(), createIdentity3(), createIdentity4()));
+ assertThat(newIdentities, containsInAnyOrder(createIdentity4()));
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, empty());
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity2(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAContextWasRemoved() {
+ Identity identity2 = createIdentity2();
+ identity2.removeContext("Context C");
+ identityChangeDetector.detectChanges(asList(createIdentity1(), identity2, createIdentity3()));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, containsInAnyOrder(identity2));
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAContextWasAdded() {
+ Identity identity2 = createIdentity2();
+ identity2.addContext("Context C1");
+ identityChangeDetector.detectChanges(asList(createIdentity1(), identity2, createIdentity3()));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, containsInAnyOrder(identity2));
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAPropertyWasRemoved() {
+ Identity identity1 = createIdentity1();
+ identity1.removeProperty("Key A");
+ identityChangeDetector.detectChanges(asList(identity1, createIdentity2(), createIdentity3()));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, containsInAnyOrder(identity1));
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity2(), createIdentity3()));
+ }
+
+ @Test
+ public void detectThatAPropertyWasAdded() {
+ Identity identity3 = createIdentity3();
+ identity3.setProperty("Key A", "Value A");
+ identityChangeDetector.detectChanges(asList(createIdentity1(), createIdentity2(), identity3));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, containsInAnyOrder(identity3));
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity2()));
+ }
+
+ @Test
+ public void detectThatAPropertyWasChanged() {
+ Identity identity3 = createIdentity3();
+ identity3.setProperty("Key E", "Value F");
+ identityChangeDetector.detectChanges(asList(createIdentity1(), createIdentity2(), identity3));
+ assertThat(newIdentities, empty());
+ assertThat(removedIdentities, empty());
+ assertThat(changedIdentities, containsInAnyOrder(identity3));
+ assertThat(unchangedIdentities, containsInAnyOrder(createIdentity1(), createIdentity2()));
+ }
+
+ private static Collection<Identity> createOldIdentities() {
+ return asList(createIdentity1(), createIdentity2(), createIdentity3());
+ }
+
+ private static Identity createIdentity1() {
+ return createIdentity("Test1", asList("Context A", "Context B"), ImmutableMap.of("Key A", "Value A", "Key B", "Value B"));
+ }
+
+ private static Identity createIdentity2() {
+ return createIdentity("Test2", asList("Context C", "Context D"), ImmutableMap.of("Key C", "Value C", "Key D", "Value D"));
+ }
+
+ private static Identity createIdentity3() {
+ return createIdentity("Test3", asList("Context E", "Context F"), ImmutableMap.of("Key E", "Value E", "Key F", "Value F"));
+ }
+
+ private static Identity createIdentity4() {
+ return createIdentity("Test4", asList("Context G", "Context H"), ImmutableMap.of("Key G", "Value G", "Key H", "Value H"));
+ }
+
+ private static Identity createIdentity(String id, Collection<String> contexts, Map<String, String> properties) {
+ DefaultIdentity identity = new DefaultIdentity(id, id, id);
+ identity.setContexts(contexts);
+ identity.setProperties(properties);
+ return identity;
+ }
+
+}