From 8a062443afbe9529468ef11407d5125f22edb970 Mon Sep 17 00:00:00 2001
From: Sam Harwell <sam@tunnelvisionlabs.com>
Date: Fri, 4 Jul 2014 20:38:40 -0500
Subject: [PATCH] Map putIfAbsent to GetOrAdd

---
 reference/sharpen-all-options.txt                      | 2 ++
 runtime/CSharp/Antlr4.Runtime/Atn/PredictionContext.cs | 4 ++--
 runtime/CSharp/Antlr4.Runtime/Dfa/DFA.cs               | 2 +-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/reference/sharpen-all-options.txt b/reference/sharpen-all-options.txt
index 790305ee9..8d4da7dab 100644
--- a/reference/sharpen-all-options.txt
+++ b/reference/sharpen-all-options.txt
@@ -23,6 +23,8 @@
 -methodMapping java.util.AbstractList.addAll AddRange 
 -methodMapping java.util.ArrayList.addAll AddRange      
 
+-methodMapping java.util.concurrent.ConcurrentMap.putIfAbsent GetOrAdd
+
 -fullyQualify File  
 -namespaceMapping java.lang.ref Antlr4.Runtime.Sharpen
 -namespaceMapping java.lang Antlr4.Runtime.Sharpen
diff --git a/runtime/CSharp/Antlr4.Runtime/Atn/PredictionContext.cs b/runtime/CSharp/Antlr4.Runtime/Atn/PredictionContext.cs
index 0c13e2c81..5e750e56c 100644
--- a/runtime/CSharp/Antlr4.Runtime/Atn/PredictionContext.cs
+++ b/runtime/CSharp/Antlr4.Runtime/Atn/PredictionContext.cs
@@ -353,7 +353,7 @@ namespace Antlr4.Runtime.Atn
             }
             if (!changed)
             {
-                existing = contextCache.PutIfAbsent(context, context);
+                existing = contextCache.GetOrAdd(context, context);
                 visited.Put(context, existing != null ? existing : context);
                 return context;
             }
@@ -368,7 +368,7 @@ namespace Antlr4.Runtime.Atn
                 ArrayPredictionContext arrayPredictionContext = (ArrayPredictionContext)context;
                 updated = new ArrayPredictionContext(parents, arrayPredictionContext.returnStates, context.cachedHashCode);
             }
-            existing = contextCache.PutIfAbsent(updated, updated);
+            existing = contextCache.GetOrAdd(updated, updated);
             visited.Put(updated, existing != null ? existing : updated);
             visited.Put(context, existing != null ? existing : updated);
             return updated;
diff --git a/runtime/CSharp/Antlr4.Runtime/Dfa/DFA.cs b/runtime/CSharp/Antlr4.Runtime/Dfa/DFA.cs
index 3fc6a7de5..6a02a0919 100644
--- a/runtime/CSharp/Antlr4.Runtime/Dfa/DFA.cs
+++ b/runtime/CSharp/Antlr4.Runtime/Dfa/DFA.cs
@@ -267,7 +267,7 @@ namespace Antlr4.Runtime.Dfa
         public virtual DFAState AddState(DFAState state)
         {
             state.stateNumber = nextStateNumber.GetAndIncrement();
-            DFAState existing = states.PutIfAbsent(state, state);
+            DFAState existing = states.GetOrAdd(state, state);
             if (existing != null)
             {
                 return existing;