| /* |
| * Copyright 2018-present Open Networking Foundation |
| * |
| * 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.cluster.impl; |
| |
| import java.lang.reflect.InvocationHandler; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.function.Function; |
| import java.util.stream.Collectors; |
| |
| import com.google.common.collect.Maps; |
| import org.onosproject.store.cluster.messaging.MessageSubject; |
| |
| /** |
| * Implementation of the proxy service. |
| */ |
| public abstract class AbstractProxyManager { |
| |
| /** |
| * Wrapper for a proxy service which handles registration of proxy methods as {@code ClusterCommunicationService} |
| * subscribers. |
| */ |
| class ProxyService { |
| private final Map<Method, OperationService> operations = Maps.newConcurrentMap(); |
| |
| ProxyService( |
| Object instance, |
| Class<?> type, |
| String prefix, |
| OperationServiceFactory syncServiceFactory, |
| OperationServiceFactory asyncServiceFactory) { |
| operations.putAll(getMethodMap(type, prefix).entrySet().stream() |
| .map(entry -> { |
| if (entry.getValue().type() == Operation.Type.SYNC) { |
| return Maps.immutableEntry( |
| entry.getKey(), |
| syncServiceFactory.create(instance, entry.getKey(), entry.getValue())); |
| } else { |
| return Maps.immutableEntry( |
| entry.getKey(), |
| asyncServiceFactory.create(instance, entry.getKey(), entry.getValue())); |
| } |
| }).collect(Collectors.toMap(e -> e.getKey(), e -> e.getValue()))); |
| } |
| |
| /** |
| * Closes the proxy service. |
| */ |
| void close() { |
| operations.values().forEach(operation -> operation.close()); |
| } |
| } |
| |
| /** |
| * Operation service factory. |
| */ |
| @FunctionalInterface |
| interface OperationServiceFactory { |
| OperationService create(Object instance, Method method, Operation operation); |
| } |
| |
| /** |
| * Wrapper for a single proxy service operation which handles registration of subscribers and invocation |
| * of service instance methods. |
| */ |
| abstract class OperationService { |
| protected final Object instance; |
| protected final Method method; |
| protected final Operation operation; |
| |
| OperationService(Object instance, Method method, Operation operation) { |
| this.instance = instance; |
| this.method = method; |
| this.operation = operation; |
| } |
| |
| /** |
| * Invokes the method with the given arguments. |
| * |
| * @param args the arguments with which to invoke the operation |
| * @param <T> the operation return type |
| * @return the operation return value |
| */ |
| @SuppressWarnings("unchecked") |
| <T> T invoke(Object[] args) { |
| try { |
| return (T) method.invoke(instance, args); |
| } catch (IllegalAccessException | InvocationTargetException e) { |
| throw new IllegalStateException(e); |
| } |
| } |
| |
| /** |
| * Closes the operation service. |
| */ |
| abstract void close(); |
| } |
| |
| /** |
| * Proxy invocation handler which routes proxy method calls to the correct node and subscriber via |
| * {@code ClusterCommunicationService}. |
| */ |
| class ProxyInvocationHandler implements InvocationHandler { |
| private final Map<Method, OperationHandler> handlers = Maps.newConcurrentMap(); |
| |
| ProxyInvocationHandler( |
| Class<?> type, |
| String prefix, |
| OperationHandlerFactory syncHandlerFactory, |
| OperationHandlerFactory asyncHandlerFactory) { |
| handlers.putAll(getMethodMap(type, prefix).entrySet().stream() |
| .map(entry -> { |
| if (entry.getValue().type() == Operation.Type.SYNC) { |
| return Maps.immutableEntry(entry.getKey(), syncHandlerFactory.create(entry.getValue())); |
| } else { |
| return Maps.immutableEntry(entry.getKey(), asyncHandlerFactory.create(entry.getValue())); |
| } |
| }).collect(Collectors.toMap(e -> e.getKey(), e -> e.getValue()))); |
| } |
| |
| @Override |
| public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { |
| OperationHandler handler = handlers.get(method); |
| if (handler == null) { |
| throw new IllegalStateException("Unknown proxy operation " + method.getName()); |
| } |
| return handler.apply(args); |
| } |
| } |
| |
| /** |
| * Operation handler factory. |
| */ |
| @FunctionalInterface |
| interface OperationHandlerFactory { |
| OperationHandler create(Operation operation); |
| } |
| |
| /** |
| * Invocation handler for an individual proxy operation. |
| */ |
| abstract class OperationHandler implements Function<Object[], Object> { |
| protected final Operation operation; |
| |
| OperationHandler(Operation operation) { |
| this.operation = operation; |
| } |
| } |
| |
| /** |
| * Recursively finds operations defined by the given type and its implemented interfaces. |
| * |
| * @param type the type for which to find operations |
| * @param prefix the prefix with which to generate message subjects |
| * @return the operations defined by the given type and its parent interfaces |
| */ |
| Map<Method, Operation> getMethodMap(Class<?> type, String prefix) { |
| String service = type.getCanonicalName().replace(".", "-"); |
| Map<Method, Operation> methods = new HashMap<>(); |
| for (Method method : type.getDeclaredMethods()) { |
| String name = method.getName(); |
| if (methods.values().stream().anyMatch(op -> op.name.equals(name))) { |
| throw new IllegalArgumentException("Method " + name + " is ambiguous"); |
| } |
| |
| Class<?> returnType = method.getReturnType(); |
| if (CompletableFuture.class.isAssignableFrom(returnType)) { |
| methods.put(method, new Operation(Operation.Type.ASYNC, prefix, service, name, method)); |
| } else { |
| methods.put(method, new Operation(Operation.Type.SYNC, prefix, service, name, method)); |
| } |
| } |
| for (Class<?> iface : type.getInterfaces()) { |
| methods.putAll(getMethodMap(iface, prefix)); |
| } |
| return methods; |
| } |
| |
| /** |
| * Simple data class for proxy operation metadata. |
| */ |
| static class Operation { |
| |
| /** |
| * Operation type. |
| */ |
| enum Type { |
| SYNC, |
| ASYNC, |
| } |
| |
| private final Type type; |
| private final String service; |
| private final String name; |
| private final Method method; |
| private final MessageSubject subject; |
| |
| Operation(Type type, String prefix, String service, String name, Method method) { |
| this.type = type; |
| this.service = service; |
| this.name = name; |
| this.method = method; |
| this.subject = new MessageSubject(String.format("%s-%s-%s", prefix, service, name)); |
| } |
| |
| /** |
| * Returns the operation type. |
| * |
| * @return the operation type |
| */ |
| Type type() { |
| return type; |
| } |
| |
| /** |
| * Returns the service name of the service to which this operation belongs. |
| * |
| * @return the service name of the service to which this operation belongs |
| */ |
| String service() { |
| return service; |
| } |
| |
| /** |
| * Returns the operation name. |
| * |
| * @return the operation name |
| */ |
| String name() { |
| return name; |
| } |
| |
| /** |
| * Returns the operation method. |
| * |
| * @return the operation method |
| */ |
| Method method() { |
| return method; |
| } |
| |
| /** |
| * Returns the operation message subject. |
| * |
| * @return the operation message subject |
| */ |
| MessageSubject subject() { |
| return subject; |
| } |
| } |
| } |