Support off-heap store and distributed caching.

Ruby objects stored in Ehcache will be automatically marshaled to a Java byte
array if the cache they are being placed in is clustered or the off-heap store
is in use. On retrieval, such Ruby objects are automatically unmarshaled before
being returned to the client. This enables the use of BigMemory and Terracotta
clustered Ehcache.

lib/ehcache/cache.rb

@@ -10,6 +10,13 @@ def each
       yield self.get(key)
     end
   end
+
+  # Does this cache require marshalling of Ruby objects?
+  def marshal?
+    config = self.cache_configuration
+    config.overflow_to_disk? || config.overflow_to_off_heap? || config.terracotta_clustered?
+  end
+
   # Gets an element value from the cache.  Unlike the #get method, this method
   # returns the element value, not the Element object.
   def [](key)
@@ -26,7 +33,10 @@ def put(*args)
     if args.size == 1 && args.first.kind_of?(Ehcache::Element)
       element = args.first
     elsif args.size == 2
-      element = Ehcache::Element.create(args[0], args[1], options)
+      if marshal?
+        value = Java::NetSfEhcache::MarshaledRubyObject.new(Marshal.dump(args[1]).to_java_bytes)
+      end
+      element = Ehcache::Element.create(args[0], value, options)
     else
       raise ArgumentError, "Must be Element object or key and value arguments"
     end

lib/ehcache/element.rb

@@ -9,6 +9,18 @@ def self.create(key, value, options = {})
     result
   end
 
+  alias element_value value
+
+  # Wrap the Element#value method to unmarshal Ruby objects if necessary.
+  def value
+    val = element_value
+    if val.kind_of?(Java::NetSfEhcache::MarshaledRubyObject)
+      Marshal.load(String.from_java_bytes(val.bytes))
+    else
+      val
+    end
+  end
+
   alias tti getTimeToIdle
   alias ttl getTimeToLive
 

src/net/sf/ehcache/MarshaledRubyObject.java

@@ -0,0 +1,15 @@
+package net.sf.ehcache;
+
+import java.io.Serializable;
+
+public class MarshaledRubyObject implements Serializable {
+  private byte[] bytes;
+
+  public MarshaledRubyObject(byte[] bytes) {
+    this.bytes = bytes;
+  }
+
+  public byte[] getBytes() {
+    return this.bytes;
+  }
+}