@@ -0,0 +1,883 @@
+/*%0A * Copyright 2016 Square Inc.%0A *%0A * Licensed under the Apache License, Version 2.0 (the %22License%22);%0A * you may not use this file except in compliance with the License.%0A * You may obtain a copy of the License at%0A *%0A *     http://www.apache.org/licenses/LICENSE-2.0%0A *%0A * Unless required by applicable law or agreed to in writing, software%0A * distributed under the License is distributed on an %22AS IS%22 BASIS,%0A * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.%0A * See the License for the specific language governing permissions and%0A * limitations under the License.%0A */%0A%0Apackage flow;%0A%0A/**%0A * Convenience base class for keys.%0A */%0Apublic abstract class ClassKey %7B%0A%0A  @Override public boolean equals(Object o) %7B%0A    return this == o %7C%7C (o != null && getClass() == o.getClass());%0A  %7D%0A%0A  @Override public int hashCode() %7B%0A    return getClass().hashCode();%0A  %7D%0A%7D%0A

add ClassKey convenience base class