Wrote learner

learner.rb

@@ -1,2 +1,29 @@
-class Learner
+class Learner < PaxosRole
+  DONT_KNOW = nil
+
+  def initialize(supervisor)
+    @supervisor = supervisor
+    @mutex_me = Mutex.new
+    @learned = {}
+    @learned_value = DONT_KNOW
+  end
+
+  def learn
+    @mutex_me.synchronize { @learned_value }
+  end
+
+  def report(value, acceptor)
+    # TODO hashcode
+    @mutex_me.synchronize do
+      @learned[acceptor] = value
+      @learned.inject(Hash.new(0)) do |m, kv|
+        if m[v] += 1 > @supervisor.replicas / 2
+          @supervisor.replicas.each do |replica|
+            replica.proposer.value_learned!
+          end
+          break @learned_value = kv.last 
+        end
+      end
+    end
+  end
 end

proposer.rb

@@ -22,7 +22,7 @@ def propose(value)
             memo << response if response
           end
 
-          next if responses.size < (replicas.size / 2.0).ceil
+          next if responses.size < replicas.size / 2
 
           number = responses.inject(nil) do |memo, response|
             if response.highest_accepted

rpc_exporter.rb

@@ -1,13 +1,20 @@
-class RPCExporter
-  attr_reader :paxos_replica
+class RPCExporter < PaxosRole
+  attr_reader :proposer, :acceptor, :learner
 
-  def initialize
-    @paxos_replica = PaxosReplica.new
+  def initialize(supervisor)
+    @proposer = Proposer.new(supervisor)
+    @acceptor = Acceptor.new(supervisor) 
+    @learner  = Learner.new(supervisor)
+    supervisor.add_replica(self)
   end
 
-  def propose
+  def propose(value)
+    @proposer.propose(value)
   end
 
   def learn
+    @learner.learn
   end
+
+  protected :proposer, :acceptor, :learner
 end