Eliminate the duplication code of `StatementPool`

1 files changed, 26 insertions, 8 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/statement_pool.rb b/activerecord/lib/active_record/connection_adapters/statement_pool.rb
index c6b1bc8b5b..82e9ef3d3d 100644
--- a/activerecord/lib/active_record/connection_adapters/statement_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/statement_pool.rb
@@ -4,35 +4,53 @@ module ActiveRecord
       include Enumerable
 
       def initialize(connection, max = 1000)
+        @cache = Hash.new { |h,pid| h[pid] = {} }
         @connection = connection
         @max        = max
       end
 
-      def each
-        raise NotImplementedError
+      def each(&block)
+        cache.each(&block)
       end
 
       def key?(key)
-        raise NotImplementedError
+        cache.key?(key)
       end
 
       def [](key)
-        raise NotImplementedError
+        cache[key]
       end
 
       def length
-        raise NotImplementedError
+        cache.length
       end
 
-      def []=(sql, key)
-        raise NotImplementedError
+      def []=(sql, stmt)
+        while @max <= cache.size
+          dealloc(cache.shift.last)
+        end
+        cache[sql] = stmt
       end
 
       def clear
-        raise NotImplementedError
+        cache.each_value do |stmt|
+          dealloc stmt
+        end
+        cache.clear
       end
 
       def delete(key)
+        dealloc cache[key]
+        cache.delete(key)
+      end
+
+      private
+
+      def cache
+        @cache[Process.pid]
+      end
+
+      def dealloc(stmt)
         raise NotImplementedError
       end
     end