ZOOKEEPER-1699. Forgot to add a new file.

git-svn-id: https://svn.apache.org/repos/asf/zookeeper/trunk@1596635 13f79535-47bb-0310-9956-ffa450edef68

src/java/main/org/apache/zookeeper/server/quorum/SyncedLearnerTracker.java

@@ -0,0 +1,82 @@
+/**
+ * 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.zookeeper.server.quorum;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+
+import org.apache.zookeeper.server.quorum.flexible.QuorumVerifier;
+
+public class SyncedLearnerTracker {
+
+    protected ArrayList<QuorumVerifierAcksetPair> qvAcksetPairs = 
+                new ArrayList<QuorumVerifierAcksetPair>();
+
+    public void addQuorumVerifier(QuorumVerifier qv) {
+        qvAcksetPairs.add(new QuorumVerifierAcksetPair(qv,
+                new HashSet<Long>(qv.getVotingMembers().size())));
+    }
+
+    public boolean addAck(Long sid) {
+        boolean change = false;
+        for (QuorumVerifierAcksetPair qvAckset : qvAcksetPairs) {
+            if (qvAckset.getQuorumVerifier().getVotingMembers().containsKey(sid)) {
+                qvAckset.getAckset().add(sid);
+                change = true;
+            }
+        }
+        return change;
+    }
+
+    public boolean hasAllQuorums() {
+        for (QuorumVerifierAcksetPair qvAckset : qvAcksetPairs) {
+            if (!qvAckset.getQuorumVerifier().containsQuorum(qvAckset.getAckset()))
+                return false;
+        }
+        return true;
+    }
+        
+    public String ackSetsToString(){
+        StringBuilder sb = new StringBuilder();
+            
+        for (QuorumVerifierAcksetPair qvAckset : qvAcksetPairs) {
+            sb.append(qvAckset.getAckset().toString()).append(",");
+        }
+            
+        return sb.substring(0, sb.length()-1);
+    }
+
+    public static class QuorumVerifierAcksetPair {
+        private final QuorumVerifier qv;
+        private final HashSet<Long> ackset;
+
+        public QuorumVerifierAcksetPair(QuorumVerifier qv, HashSet<Long> ackset) {                
+            this.qv = qv;
+            this.ackset = ackset;
+        }
+
+        public QuorumVerifier getQuorumVerifier() {
+            return this.qv;
+        }
+
+        public HashSet<Long> getAckset() {
+            return this.ackset;
+        }
+    }
+}