Merge branch 'master' of https://github.com/AlibabaTech/dubbo

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/support/RpcUtils.java

@@ -152,8 +152,8 @@ public class RpcUtils {
     public static boolean isAsync(URL url, Invocation inv) {
     	boolean isAsync ;
     	//如果Java代码中设置优先.
-    	if (Boolean.FALSE.toString().equals(inv.getAttachment(Constants.ASYNC_KEY))) {
-    		isAsync = false;
+    	if (Boolean.TRUE.toString().equals(inv.getAttachment(Constants.ASYNC_KEY))) {
+    		isAsync = true;
     	} else {
 	    	isAsync = url.getMethodParameter(getMethodName(inv), Constants.ASYNC_KEY, false);
     	}