You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@gossip.apache.org by ec...@apache.org on 2017/02/22 21:41:40 UTC
incubator-gossip git commit: GOSSIP-53 CRDT types
Repository: incubator-gossip
Updated Branches:
refs/heads/master 400cb40cb -> b71be5e16
GOSSIP-53 CRDT types
Project: http://git-wip-us.apache.org/repos/asf/incubator-gossip/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-gossip/commit/b71be5e1
Tree: http://git-wip-us.apache.org/repos/asf/incubator-gossip/tree/b71be5e1
Diff: http://git-wip-us.apache.org/repos/asf/incubator-gossip/diff/b71be5e1
Branch: refs/heads/master
Commit: b71be5e16a0a2b5b64a00a53604eb7446e92ca4a
Parents: 400cb40
Author: Edward Capriolo <ed...@gmail.com>
Authored: Sun Feb 19 16:14:30 2017 -0500
Committer: Edward Capriolo <ed...@gmail.com>
Committed: Sun Feb 19 16:14:30 2017 -0500
----------------------------------------------------------------------
.../java/org/apache/gossip/GossipService.java | 1 +
src/main/java/org/apache/gossip/crdt/Crdt.java | 39 +++++
.../apache/gossip/crdt/CrdtBiFunctionMerge.java | 55 ++++++
.../java/org/apache/gossip/crdt/CrdtSet.java | 26 +++
.../org/apache/gossip/crdt/GrowOnlySet.java | 168 +++++++++++++++++++
.../org/apache/gossip/manager/GossipCore.java | 52 +++++-
.../apache/gossip/manager/GossipManager.java | 26 +++
src/test/java/org/apache/gossip/DataTest.java | 68 +++++---
.../org/apache/gossip/crdt/GrowOnlySetTest.java | 38 +++++
9 files changed, 439 insertions(+), 34 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/GossipService.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/GossipService.java b/src/main/java/org/apache/gossip/GossipService.java
index f32eb35..f216c33 100644
--- a/src/main/java/org/apache/gossip/GossipService.java
+++ b/src/main/java/org/apache/gossip/GossipService.java
@@ -131,4 +131,5 @@ public class GossipService {
public SharedGossipDataMessage findSharedData(String key){
return getGossipManager().findSharedGossipData(key);
}
+
}
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/crdt/Crdt.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/crdt/Crdt.java b/src/main/java/org/apache/gossip/crdt/Crdt.java
new file mode 100644
index 0000000..8edfa8c
--- /dev/null
+++ b/src/main/java/org/apache/gossip/crdt/Crdt.java
@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.crdt;
+/**
+ *
+ * Immutable type
+ *
+ * @param <SetType>
+ * @param <MergeReturnType>
+ */
+public interface Crdt<SetType, MergeReturnType extends Crdt<SetType, MergeReturnType>> {
+
+
+ MergeReturnType merge(MergeReturnType other);
+ SetType value();
+ /**
+ * Called to self optimize. Some CRDTs may use some mechanism to clean up be
+ * removing obsolete data outside the scope of merging. IE this could clean up
+ * temporal values, old copies etc.
+ * @return the Crdt structure optimized
+ */
+ MergeReturnType optimize();
+
+}
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/crdt/CrdtBiFunctionMerge.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/crdt/CrdtBiFunctionMerge.java b/src/main/java/org/apache/gossip/crdt/CrdtBiFunctionMerge.java
new file mode 100644
index 0000000..1ac7a30
--- /dev/null
+++ b/src/main/java/org/apache/gossip/crdt/CrdtBiFunctionMerge.java
@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.crdt;
+
+import java.util.function.BiFunction;
+
+@SuppressWarnings("rawtypes")
+public class CrdtBiFunctionMerge implements BiFunction<Crdt,Crdt,Crdt> {
+
+ @SuppressWarnings("unchecked")
+ @Override
+ public Crdt apply(Crdt t, Crdt u) {
+ if (t == null && u == null){
+ return null;
+ } else if (t == null){
+ return u;
+ } else if (u == null){
+ return t;
+ }
+ if (! u.getClass().equals(t.getClass())){
+ throw new IllegalArgumentException( "Can not merge " + t.getClass() + " "+ u.getClass());
+ }
+ return t.merge(u);
+ }
+
+ @SuppressWarnings("unchecked")
+ public static Crdt applyStatic(Crdt t, Crdt u){
+ if (t == null && u == null){
+ return null;
+ } else if (t == null){
+ return u;
+ } else if (u == null){
+ return t;
+ }
+ if (! u.getClass().equals(t.getClass())){
+ throw new IllegalArgumentException( "Can not merge " + t.getClass() + " "+ u.getClass());
+ }
+ return t.merge(u);
+ }
+}
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/crdt/CrdtSet.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/crdt/CrdtSet.java b/src/main/java/org/apache/gossip/crdt/CrdtSet.java
new file mode 100644
index 0000000..3a5fbca
--- /dev/null
+++ b/src/main/java/org/apache/gossip/crdt/CrdtSet.java
@@ -0,0 +1,26 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.crdt;
+
+import java.util.Set;
+
+public interface CrdtSet<ElementType, SetType extends Set<ElementType>, R extends CrdtSet<ElementType, SetType, R>>
+extends Crdt<SetType, R>, Set<ElementType> {
+
+}
+
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/crdt/GrowOnlySet.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/crdt/GrowOnlySet.java b/src/main/java/org/apache/gossip/crdt/GrowOnlySet.java
new file mode 100644
index 0000000..0b1771b
--- /dev/null
+++ b/src/main/java/org/apache/gossip/crdt/GrowOnlySet.java
@@ -0,0 +1,168 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.crdt;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+public class GrowOnlySet<ElementType> implements CrdtSet<ElementType, Set<ElementType>, GrowOnlySet<ElementType>>{
+
+ private final Set<ElementType> hidden = new LinkedHashSet<>();
+
+ @SuppressWarnings("unused")
+ /*
+ * Used by SerDe
+ */
+ private GrowOnlySet(){
+
+ }
+
+ public GrowOnlySet(Set<ElementType> c){
+ hidden.addAll(c);
+ }
+
+ public GrowOnlySet(Collection<ElementType> c){
+ hidden.addAll(c);
+ }
+
+ public GrowOnlySet(GrowOnlySet<ElementType> first, GrowOnlySet<ElementType> second){
+ hidden.addAll(first.value());
+ hidden.addAll(second.value());
+ }
+
+ @Override
+ public GrowOnlySet<ElementType> merge(GrowOnlySet<ElementType> other) {
+ return new GrowOnlySet<>(this, other);
+ }
+
+ @Override
+ public Set<ElementType> value() {
+ Set<ElementType> copy = new LinkedHashSet<>();
+ copy.addAll(hidden);
+ return Collections.unmodifiableSet(copy);
+ }
+
+ @Override
+ public GrowOnlySet<ElementType> optimize() {
+ return new GrowOnlySet<>(hidden);
+ }
+
+ @Override
+ public int size() {
+ return hidden.size();
+ }
+
+ @Override
+ public boolean isEmpty() {
+ return hidden.isEmpty();
+ }
+
+ @Override
+ public boolean contains(Object o) {
+ return hidden.contains(o);
+ }
+
+ @Override
+ public Iterator<ElementType> iterator() {
+ Set<ElementType> copy = new HashSet<>();
+ copy.addAll(hidden);
+ return copy.iterator();
+ }
+
+ @Override
+ public Object[] toArray() {
+ return hidden.toArray();
+ }
+
+ @Override
+ public <T> T[] toArray(T[] a) {
+ return hidden.toArray(a);
+ }
+
+ @Override
+ public boolean add(ElementType e) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public boolean remove(Object o) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public boolean containsAll(Collection<?> c) {
+ return hidden.containsAll(c);
+ }
+
+ @Override
+ public boolean addAll(Collection<? extends ElementType> c) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public boolean retainAll(Collection<?> c) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public boolean removeAll(Collection<?> c) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public void clear() {
+ throw new UnsupportedOperationException();
+
+ }
+
+ @Override
+ public String toString() {
+ return "GrowOnlySet [hidden=" + hidden + "]";
+ }
+
+ @Override
+ public int hashCode() {
+ final int prime = 31;
+ int result = 1;
+ result = prime * result + ((hidden == null) ? 0 : hidden.hashCode());
+ return result;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ @SuppressWarnings("rawtypes")
+ GrowOnlySet other = (GrowOnlySet) obj;
+ if (hidden == null) {
+ if (other.hidden != null)
+ return false;
+ } else if (!hidden.equals(other.hidden))
+ return false;
+ return true;
+ }
+
+}
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/manager/GossipCore.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/manager/GossipCore.java b/src/main/java/org/apache/gossip/manager/GossipCore.java
index 403acf4..de54597 100644
--- a/src/main/java/org/apache/gossip/manager/GossipCore.java
+++ b/src/main/java/org/apache/gossip/manager/GossipCore.java
@@ -23,6 +23,7 @@ import com.codahale.metrics.MetricRegistry;
import org.apache.gossip.GossipMember;
import org.apache.gossip.LocalGossipMember;
import org.apache.gossip.RemoteGossipMember;
+import org.apache.gossip.crdt.Crdt;
import org.apache.gossip.event.GossipState;
import org.apache.gossip.model.*;
import org.apache.gossip.udp.Trackable;
@@ -111,15 +112,27 @@ public class GossipCore implements GossipCoreConstants {
}
}
- public void addSharedData(SharedGossipDataMessage message){
- SharedGossipDataMessage previous = sharedData.get(message.getKey());
- if (previous == null){
- sharedData.putIfAbsent(message.getKey(), message);
- } else {
- if (previous.getTimestamp() < message.getTimestamp()){
- sharedData.replace(message.getKey(), previous, message);
- }
- }
+ @SuppressWarnings({ "unchecked", "rawtypes" })
+ public void addSharedData(SharedGossipDataMessage message) {
+ SharedGossipDataMessage previous = sharedData.get(message.getKey());
+ if (previous == null) {
+ sharedData.putIfAbsent(message.getKey(), message);
+ } else {
+ if (message.getPayload() instanceof Crdt){
+ SharedGossipDataMessage m = sharedData.get(message.getKey());
+ SharedGossipDataMessage merged = new SharedGossipDataMessage();
+ merged.setExpireAt(message.getExpireAt());
+ merged.setKey(m.getKey());
+ merged.setNodeId(message.getNodeId());
+ merged.setTimestamp(message.getTimestamp());
+ merged.setPayload( ((Crdt) message.getPayload()).merge((Crdt)m.getPayload()));
+ sharedData.put(m.getKey(), merged);
+ } else {
+ if (previous.getTimestamp() < message.getTimestamp()) {
+ sharedData.replace(message.getKey(), previous, message);
+ }
+ }
+ }
}
public void addPerNodeData(GossipDataMessage message){
@@ -345,4 +358,25 @@ public class GossipCore implements GossipCoreConstants {
"Dead " + gossipManager.getDeadMembers()+ "\n" +
"=======================");
}
+
+ @SuppressWarnings("rawtypes")
+ public Crdt merge(SharedGossipDataMessage message) {
+ for (;;){
+ SharedGossipDataMessage ret = sharedData.putIfAbsent(message.getKey(), message);
+ if (ret == null){
+ return (Crdt) message.getPayload();
+ }
+ SharedGossipDataMessage copy = new SharedGossipDataMessage();
+ copy.setExpireAt(message.getExpireAt());
+ copy.setKey(message.getKey());
+ copy.setNodeId(message.getNodeId());
+ @SuppressWarnings("unchecked")
+ Crdt merged = ((Crdt) ret.getPayload()).merge((Crdt) message.getPayload());
+ message.setPayload(merged);
+ boolean replaced = sharedData.replace(message.getKey(), ret, copy);
+ if (replaced){
+ return merged;
+ }
+ }
+ }
}
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/main/java/org/apache/gossip/manager/GossipManager.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/gossip/manager/GossipManager.java b/src/main/java/org/apache/gossip/manager/GossipManager.java
index ab8e4ae..0140f00 100644
--- a/src/main/java/org/apache/gossip/manager/GossipManager.java
+++ b/src/main/java/org/apache/gossip/manager/GossipManager.java
@@ -22,6 +22,7 @@ import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.gossip.GossipMember;
import org.apache.gossip.GossipSettings;
import org.apache.gossip.LocalGossipMember;
+import org.apache.gossip.crdt.Crdt;
import org.apache.gossip.event.GossipListener;
import org.apache.gossip.event.GossipState;
import org.apache.gossip.manager.handlers.MessageInvoker;
@@ -291,6 +292,31 @@ public abstract class GossipManager {
gossipCore.addSharedData(message);
}
+
+ @SuppressWarnings("rawtypes")
+ public Crdt findCrdt(String key){
+ SharedGossipDataMessage l = gossipCore.getSharedData().get(key);
+ if (l == null){
+ return null;
+ }
+ if (l.getExpireAt() < clock.currentTimeMillis()){
+ return null;
+ } else {
+ return (Crdt) l.getPayload();
+ }
+ }
+
+ @SuppressWarnings("rawtypes")
+ public Crdt merge(SharedGossipDataMessage message){
+ Objects.nonNull(message.getKey());
+ Objects.nonNull(message.getTimestamp());
+ Objects.nonNull(message.getPayload());
+ message.setNodeId(me.getId());
+ if (! (message.getPayload() instanceof Crdt)){
+ throw new IllegalArgumentException("Not a subclass of CRDT " + message.getPayload());
+ }
+ return gossipCore.merge(message);
+ }
public GossipDataMessage findPerNodeGossipData(String nodeId, String key){
ConcurrentHashMap<String, GossipDataMessage> j = gossipCore.getPerNodeData().get(nodeId);
if (j == null){
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/test/java/org/apache/gossip/DataTest.java
----------------------------------------------------------------------
diff --git a/src/test/java/org/apache/gossip/DataTest.java b/src/test/java/org/apache/gossip/DataTest.java
index b5fa705..f05636b 100644
--- a/src/test/java/org/apache/gossip/DataTest.java
+++ b/src/test/java/org/apache/gossip/DataTest.java
@@ -22,12 +22,13 @@ import java.net.URI;
import java.net.URISyntaxException;
import java.net.UnknownHostException;
import java.util.ArrayList;
+import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.UUID;
-import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
+import org.apache.gossip.crdt.GrowOnlySet;
import org.apache.gossip.model.GossipDataMessage;
import org.apache.gossip.model.SharedGossipDataMessage;
import org.junit.Test;
@@ -58,43 +59,60 @@ public class DataTest {
clients.add(gossipService);
gossipService.start();
}
- TUnit.assertThat(new Callable<Integer> (){
- public Integer call() throws Exception {
- int total = 0;
- for (int i = 0; i < clusterMembers; ++i) {
- total += clients.get(i).getGossipManager().getLiveMembers().size();
- }
- return total;
- }}).afterWaitingAtMost(20, TimeUnit.SECONDS).isEqualTo(2);
+ TUnit.assertThat(() -> {
+ int total = 0;
+ for (int i = 0; i < clusterMembers; ++i) {
+ total += clients.get(i).getGossipManager().getLiveMembers().size();
+ }
+ return total;
+ }).afterWaitingAtMost(20, TimeUnit.SECONDS).isEqualTo(2);
clients.get(0).gossipPerNodeData(msg());
clients.get(0).gossipSharedData(sharedMsg());
- TUnit.assertThat(new Callable<Object>() {
- public Object call() throws Exception {
- GossipDataMessage x = clients.get(1).findPerNodeData(1 + "", "a");
- if (x == null)
- return "";
- else
- return x.getPayload();
- }
+ TUnit.assertThat(()-> {
+ GossipDataMessage x = clients.get(1).findPerNodeData(1 + "", "a");
+ if (x == null)
+ return "";
+ else
+ return x.getPayload();
}).afterWaitingAtMost(20, TimeUnit.SECONDS).isEqualTo("b");
- TUnit.assertThat(new Callable<Object>() {
- public Object call() throws Exception {
- SharedGossipDataMessage x = clients.get(1).findSharedData("a");
- if (x == null)
- return "";
- else
- return x.getPayload();
- }
+ TUnit.assertThat(() -> {
+ SharedGossipDataMessage x = clients.get(1).findSharedData("a");
+ if (x == null)
+ return "";
+ else
+ return x.getPayload();
}).afterWaitingAtMost(20, TimeUnit.SECONDS).isEqualTo("c");
+ givenDifferentDatumsInSet(clients);
+ assertThatListIsMerged(clients);
for (int i = 0; i < clusterMembers; ++i) {
clients.get(i).shutdown();
}
}
+ private void givenDifferentDatumsInSet(final List<GossipService> clients){
+ clients.get(0).getGossipManager().merge(CrdtMessage("1"));
+ clients.get(1).getGossipManager().merge(CrdtMessage("2"));
+ }
+
+ private void assertThatListIsMerged(final List<GossipService> clients){
+ TUnit.assertThat(() -> {
+ return clients.get(0).getGossipManager().findCrdt("cr");
+ }).afterWaitingAtMost(10, TimeUnit.SECONDS).equals(new GrowOnlySet<String>(Arrays.asList("1","2")));
+ }
+
+ private SharedGossipDataMessage CrdtMessage(String item){
+ SharedGossipDataMessage d = new SharedGossipDataMessage();
+ d.setKey("cr");
+ d.setPayload(new GrowOnlySet<String>( Arrays.asList(item)));
+ d.setExpireAt(Long.MAX_VALUE);
+ d.setTimestamp(System.currentTimeMillis());
+ return d;
+ }
+
private GossipDataMessage msg(){
GossipDataMessage g = new GossipDataMessage();
g.setExpireAt(Long.MAX_VALUE);
http://git-wip-us.apache.org/repos/asf/incubator-gossip/blob/b71be5e1/src/test/java/org/apache/gossip/crdt/GrowOnlySetTest.java
----------------------------------------------------------------------
diff --git a/src/test/java/org/apache/gossip/crdt/GrowOnlySetTest.java b/src/test/java/org/apache/gossip/crdt/GrowOnlySetTest.java
new file mode 100644
index 0000000..d4f12b6
--- /dev/null
+++ b/src/test/java/org/apache/gossip/crdt/GrowOnlySetTest.java
@@ -0,0 +1,38 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.gossip.crdt;
+
+import java.util.Arrays;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class GrowOnlySetTest {
+
+ @SuppressWarnings("rawtypes")
+ @Test
+ public void mergeTest(){
+ ConcurrentHashMap<String, Crdt> a = new ConcurrentHashMap<>();
+ GrowOnlySet<String> gset = new GrowOnlySet<>(Arrays.asList("a", "b"));
+ Assert.assertEquals(gset, a.merge("a", gset, new CrdtBiFunctionMerge()));
+ GrowOnlySet<String> over = new GrowOnlySet<>(Arrays.asList("b", "d"));
+ Assert.assertEquals(new GrowOnlySet<>(Arrays.asList("a", "b", "d")),
+ a.merge("a", over, CrdtBiFunctionMerge::applyStatic));
+ }
+}