From 3aa5302b0035412a9cccb00a34960e997a680c9b Mon Sep 17 00:00:00 2001
From: Michael Bayne <mdb@threerings.net>
Date: Thu, 16 Aug 2001 03:25:14 +0000
Subject: [PATCH] Moved the stream related methods into a separate streamable
 interface that can be implemented by objects that are streamable but that
 don't have an associated type code.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@263 542714f4-19e9-0310-aa3c-eee0fc999fb1
---
 .../threerings/presents/io/Streamable.java    | 36 +++++++++++++++++++
 .../threerings/presents/io/TypedObject.java   | 20 ++---------
 2 files changed, 38 insertions(+), 18 deletions(-)
 create mode 100644 src/java/com/threerings/presents/io/Streamable.java

diff --git a/src/java/com/threerings/presents/io/Streamable.java b/src/java/com/threerings/presents/io/Streamable.java
new file mode 100644
index 000000000..5b3a1f1d8
--- /dev/null
+++ b/src/java/com/threerings/presents/io/Streamable.java
@@ -0,0 +1,36 @@
+//
+// $Id: Streamable.java,v 1.1 2001/08/16 03:25:14 mdb Exp $
+
+package com.threerings.cocktail.cher.io;
+
+import java.io.IOException;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+
+/**
+ * A streamable is an object that knows how to read and write itself on a
+ * stream. We are obliged to reimplement an object serialization framework
+ * rather than use the one provided by Java because we're interested in
+ * taking maximal advantage of situations where we know the types of
+ * objects that are being streamed and in those cases we avoid writing
+ * type information for the objects and only write the values. In other
+ * cases, we assign unique codes to object classes (see {@link
+ * TypedObject}) to minimize the network footprint of the serialized
+ * objects.
+ */
+public interface Streamable
+{
+    /**
+     * Writes all of the members of this object to the supplied data
+     * output stream.
+     */
+    public void writeTo (DataOutputStream out)
+        throws IOException;
+
+    /**
+     * Reads all of the members of this object in from the supplied data
+     * input stream.
+     */
+    public void readFrom (DataInputStream in)
+        throws IOException;
+}
diff --git a/src/java/com/threerings/presents/io/TypedObject.java b/src/java/com/threerings/presents/io/TypedObject.java
index 17abf934c..0ba3125fe 100644
--- a/src/java/com/threerings/presents/io/TypedObject.java
+++ b/src/java/com/threerings/presents/io/TypedObject.java
@@ -1,12 +1,8 @@
 //
-// $Id: TypedObject.java,v 1.3 2001/05/30 23:58:31 mdb Exp $
+// $Id: TypedObject.java,v 1.4 2001/08/16 03:25:14 mdb Exp $
 
 package com.threerings.cocktail.cher.io;
 
-import java.io.IOException;
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-
 /**
  * A typed object is one that is associated with a particular type code.
  * The type code can be communicated on the wire and used by the receiving
@@ -15,7 +11,7 @@ import java.io.DataOutputStream;
  *
  * @see TypedObjectFactory
  */
-public interface TypedObject
+public interface TypedObject extends Streamable
 {
     /**
      * Each typed object class must associate itself with a type value via
@@ -26,16 +22,4 @@ public interface TypedObject
      * @return The type code associated with this object.
      */
     public short getType ();
-
-    /**
-     * Each typed object class must be able to write itself to a stream.
-     */
-    public void writeTo (DataOutputStream out)
-        throws IOException;
-
-    /**
-     * Each typed object class must be able to read itself from a stream.
-     */
-    public void readFrom (DataInputStream in)
-        throws IOException;
 }