| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.cassandra.distributed.util.byterewrite; |
| |
| import java.util.Arrays; |
| import java.util.EnumSet; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import net.bytebuddy.ByteBuddy; |
| import net.bytebuddy.dynamic.DynamicType; |
| import net.bytebuddy.dynamic.loading.ClassLoadingStrategy; |
| import net.bytebuddy.implementation.MethodDelegation; |
| import net.bytebuddy.implementation.bind.annotation.SuperCall; |
| import org.apache.cassandra.distributed.impl.InstanceIDDefiner; |
| import org.apache.cassandra.distributed.util.TwoWay; |
| import org.apache.cassandra.service.StorageService; |
| import org.apache.cassandra.utils.Shared; |
| |
| import static net.bytebuddy.matcher.ElementMatchers.named; |
| |
| public class StatusChangeListener |
| { |
| public enum Status |
| { |
| LEAVING("startLeaving"), |
| LEAVE("leaveRing"); |
| |
| private final String method; |
| |
| Status(String method) |
| { |
| this.method = method; |
| } |
| } |
| |
| public static void install(ClassLoader cl, int node, Status first, Status... rest) |
| { |
| install(cl, node, EnumSet.of(first, rest)); |
| } |
| |
| public static void install(ClassLoader cl, int node, Set<Status> statuses) |
| { |
| if (statuses.isEmpty()) throw new IllegalStateException("Need a set of status to listen to"); |
| |
| State.hooks.put(node, new Hooks()); |
| DynamicType.Builder<StorageService> builder = new ByteBuddy().rebase(StorageService.class); |
| for (Status s : statuses) |
| builder = builder.method(named(s.method)).intercept(MethodDelegation.to(BB.class)); |
| builder.make().load(cl, ClassLoadingStrategy.Default.INJECTION); |
| } |
| |
| public static void close() |
| { |
| for (Hooks hook : State.hooks.values()) |
| hook.close(); |
| } |
| |
| public static Hooks hooks(int node) |
| { |
| return Objects.requireNonNull(State.hooks.get(node), "Unknown node" + node); |
| } |
| |
| @Shared |
| public static class State |
| { |
| public static final Map<Integer, Hooks> hooks = new ConcurrentHashMap<>(); |
| } |
| |
| @Shared |
| public static class Hooks implements AutoCloseable |
| { |
| public static final TwoWay leaving = new TwoWay(); |
| public static final TwoWay leave = new TwoWay(); |
| |
| @Override |
| public void close() |
| { |
| for (TwoWay condition: Arrays.asList(leaving, leave)) |
| condition.close(); |
| } |
| } |
| |
| public static class BB |
| { |
| private static volatile int NODE = -1; |
| |
| public static void startLeaving(@SuperCall Runnable zuper) |
| { |
| // see org.apache.cassandra.service.StorageService.startLeaving |
| hooks().leaving.enter(); |
| zuper.run(); |
| } |
| |
| public static void leaveRing(@SuperCall Runnable zuper) |
| { |
| // see org.apache.cassandra.service.StorageService.leaveRing |
| hooks().leave.enter(); |
| zuper.run(); |
| } |
| |
| private static Hooks hooks() |
| { |
| return State.hooks.get(node()); |
| } |
| |
| private static int node() |
| { |
| int node = NODE; |
| if (node == -1) |
| node = NODE = Integer.parseInt(InstanceIDDefiner.getInstanceId().replace("node", "")); |
| return node; |
| } |
| } |
| } |