ONOS-2382: Define a new resource management API
Change-Id: I8abbb30967a7f99ea96b22613b40b2bc0a0ce73c
diff --git a/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java b/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java
new file mode 100644
index 0000000..3322362
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+++ b/core/api/src/main/java/org/onosproject/net/newresource/ResourceService.java
@@ -0,0 +1,128 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.net.newresource;
+
+import com.google.common.annotations.Beta;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Service for allocating/releasing resource(s) and retrieving allocation(s) and availability.
+ */
+@Beta
+public interface ResourceService {
+ /**
+ * Allocates the specified resource to the specified user.
+ *
+ * @param consumer resource user which the resource is allocated to
+ * @param resource resource to be allocated
+ * @param <S> type of the subject which this resource belongs to
+ * @param <T> type of the resource
+ * @return allocation information enclosed by Optional. If the allocation fails, the return value is empty
+ */
+ <S, T> Optional<ResourceAllocation<S, T>> allocate(ResourceConsumer consumer, Resource<S, T> resource);
+
+ /**
+ * Transactionally allocates the specified resources to the specified user.
+ * All allocations are made when this method succeeds, or no allocation is made when this method fails.
+ *
+ * @param consumer resource user which the resources are allocated to
+ * @param resources resources to be allocated
+ * @return non-empty list of allocation information if succeeded, otherwise empty list
+ */
+ List<ResourceAllocation<?, ?>> allocate(ResourceConsumer consumer, List<? extends Resource<?, ?>> resources);
+
+ /**
+ * Transactionally allocates the specified resources to the specified user.
+ * All allocations are made when this method succeeds, or no allocation is made when this method fails.
+ *
+ * @param consumer resource user which the resources are allocated to
+ * @param resources resources to be allocated
+ * @return non-empty list of allocation information if succeeded, otherwise empty list
+ */
+ List<ResourceAllocation<?, ?>> allocate(ResourceConsumer consumer, Resource<?, ?>... resources);
+
+ /**
+ * Releases the specified resource allocation.
+ *
+ * @param allocation resource allocation to be released
+ * @param <S> type of the subject which this resource belongs to
+ * @param <T> type of the device resource
+ * @return true if succeeded, otherwise false
+ */
+ <S, T> boolean release(ResourceAllocation<S, T> allocation);
+
+ /**
+ * Transactionally releases the specified resource allocations.
+ * All allocations are released when this method succeeded, or no allocation is released when this method fails.
+ *
+ * @param allocations resource allocations to be released
+ * @return true if succeeded, otherwise false
+ */
+ boolean release(List<? extends ResourceAllocation<?, ?>> allocations);
+
+ /**
+ * Transactionally releases the specified resource allocations.
+ * All allocations are released when this method succeeded, or no allocation is released when this method fails.
+ *
+ * @param allocations resource allocations to be released
+ * @return true if succeeded, otherwise false
+ */
+ boolean release(ResourceAllocation<?, ?>... allocations);
+
+ /**
+ * Transactionally releases the resources allocated to the specified consumer.
+ * All allocations are released when this method succeeded, or no allocation is released when this method fails.
+ *
+ * @param consumer consumer whose allocated resources are to be released
+ * @return true if succeeded, otherwise false
+ */
+ boolean release(ResourceConsumer consumer);
+
+ /**
+ * Returns allocated resources in the specified subject regarding the specified resource type.
+ *
+ * @param subject subject where resource allocations are obtained
+ * @param cls class to specify a type of resource
+ * @param <S> type of the subject
+ * @param <T> type of the resource
+ * @return non-empty collection of resource allocations if resources are allocated with the subject and type,
+ * empty collection if no resource is allocated with the subject and type
+ */
+ <S, T> Collection<ResourceAllocation<S, T>> getResourceAllocations(S subject, Class<T> cls);
+
+ /**
+ * Returns resources allocated to the specified consumer.
+ *
+ * @param consumer consumer whose allocated resources are to be returned
+ * @return resources allocated to the consumer
+ */
+ Collection<ResourceAllocation<?, ?>> getResourceAllocations(ResourceConsumer consumer);
+
+ /**
+ * Returns the availability of the specified device resource.
+ *
+ * @param resource resource to check the availability
+ * @param <S> type of the subject
+ * @param <T> type of the resource
+ * @return true if available, otherwise false
+ */
+ <S, T> boolean isAvailable(Resource<S, T> resource);
+
+ // TODO: listener and event mechanism need to be considered
+}