1 files changed, 37 insertions, 4 deletions
diff --git a/guava-gwt/src/com/google/common/collect/ImmutableSortedMap_CustomFieldSerializer.java b/guava-gwt/src/com/google/common/collect/ImmutableSortedMap_CustomFieldSerializer.java
index 70cf908..6293686 100644
--- a/guava-gwt/src/com/google/common/collect/ImmutableSortedMap_CustomFieldSerializer.java
+++ b/guava-gwt/src/com/google/common/collect/ImmutableSortedMap_CustomFieldSerializer.java
@@ -16,11 +16,44 @@
 
 package com.google.common.collect;
 
+import com.google.gwt.user.client.rpc.SerializationException;
+import com.google.gwt.user.client.rpc.SerializationStreamReader;
+import com.google.gwt.user.client.rpc.SerializationStreamWriter;
+import com.google.gwt.user.client.rpc.core.java.util.Map_CustomFieldSerializerBase;
+
+import java.util.Comparator;
+import java.util.SortedMap;
+import java.util.TreeMap;
+
 /**
- * Even though {@link ImmutableSortedMap} cannot be instantiated, we still need a custom field
- * serializer. TODO(cpovirk): why? Does it help if ensure that the GWT and non-GWT classes have the
- * same fields? Is that worth the trouble?
+ * This class implements the GWT serialization of {@link ImmutableSortedMap}.
  *
  * @author Chris Povirk
  */
-public final class ImmutableSortedMap_CustomFieldSerializer {}
+public class ImmutableSortedMap_CustomFieldSerializer {
+  public static void deserialize(SerializationStreamReader reader,
+      ImmutableSortedMap<?, ?> instance) {
+  }
+
+  public static ImmutableSortedMap<?, ?> instantiate(
+      SerializationStreamReader reader) throws SerializationException {
+    /*
+     * Nothing we can do, but we're already assuming the serialized form is
+     * correctly typed, anyway.
+     */
+    @SuppressWarnings("unchecked")
+    Comparator<Object> comparator = (Comparator<Object>) reader.readObject();
+
+    SortedMap<Object, Object> entries = new TreeMap<Object, Object>(comparator);
+    Map_CustomFieldSerializerBase.deserialize(reader, entries);
+
+    return ImmutableSortedMap.orderedBy(comparator).putAll(entries).build();
+  }
+
+  public static void serialize(SerializationStreamWriter writer,
+      ImmutableSortedMap<?, ?> instance) throws SerializationException {
+    writer.writeObject(instance.comparator());
+
+    Map_CustomFieldSerializerBase.serialize(writer, instance);
+  }
+}