diff --git a/java/src/main/java/org/msgpack/template/DefaultTemplate.java b/java/src/main/java/org/msgpack/template/DefaultTemplate.java
index 45d84f3f..f94e2f13 100644
--- a/java/src/main/java/org/msgpack/template/DefaultTemplate.java
+++ b/java/src/main/java/org/msgpack/template/DefaultTemplate.java
@@ -43,7 +43,7 @@ public class DefaultTemplate implements Template {
 	public void pack(Packer pk, Object target) throws IOException {
 		if(messagePackable) {
 			if(target == null) {
-				throw new MessageTypeException("target is null: " + target.getClass().getName());
+				throw new MessageTypeException("target is null.");
 			}
 			((MessagePackable)target).messagePack(pk);
 			return;