[MSGPACK-83] Gracefully handling new enum value with OrdinalEnum.

Takanori Takase · Takanori Takase · commit e8f0662fdf40 · 2013-01-19T16:12:46.000+09:00
diff --git a/src/main/java/org/msgpack/annotation/OrdinalEnum.java b/src/main/java/org/msgpack/annotation/OrdinalEnum.java
@@ -22,7 +22,24 @@
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.msgpack.MessageTypeException;
+import org.msgpack.template.OrdinalEnumTemplate;
+
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)
 public @interface OrdinalEnum {
+
+	/**
+	 * Specify whether the ordinal index lookup should be handled strictly or
+	 * not when mapping ordinal value to an enum value. By specifying true,
+	 * {@link MessageTypeException} will be thrown if the enum specified by the
+	 * ordinal value does not exist in this implementation. If false, then the
+	 * missing ordinal value treated as null, gracefully handling the lookup.
+	 * Default is true.
+	 * 
+	 * @since 0.6.8
+	 * @see OrdinalEnumTemplate
+	 */
+	boolean strict() default true;
+
 }
diff --git a/src/main/java/org/msgpack/template/OrdinalEnumTemplate.java b/src/main/java/org/msgpack/template/OrdinalEnumTemplate.java
@@ -21,19 +21,23 @@
 import java.util.HashMap;
 
 import org.msgpack.MessageTypeException;
+import org.msgpack.annotation.OrdinalEnum;
 import org.msgpack.packer.Packer;
 import org.msgpack.unpacker.Unpacker;
 
 public class OrdinalEnumTemplate<T> extends AbstractTemplate<T> {
     protected T[] entries;
     protected HashMap<T, Integer> reverse;
+    protected boolean strict;
 
     public OrdinalEnumTemplate(Class<T> targetClass) {
         entries = targetClass.getEnumConstants();
         reverse = new HashMap<T, Integer>();
         for (int i = 0; i < entries.length; i++) {
             reverse.put(entries[i], i);
         }
+		strict = !targetClass.isAnnotationPresent(OrdinalEnum.class)
+				|| targetClass.getAnnotation(OrdinalEnum.class).strict();
     }
 
     @Override
@@ -61,10 +65,17 @@ public T read(Unpacker pac, T to, boolean required) throws IOException,
         }
 
         int ordinal = pac.readInt();
-        if (entries.length <= ordinal) {
-            throw new MessageTypeException(
-                    new IllegalArgumentException("ordinal: " + ordinal));
-        }
-        return entries[ordinal];
+
+		if (ordinal < entries.length) {
+			return entries[ordinal];
+		}
+
+		if (!strict) {
+			return null;
+		}
+
+		throw new MessageTypeException(new IllegalArgumentException("ordinal: "
+				+ ordinal));
+
     }
 }
