curator-master/curator-test/src/main/java/org/apache/curator/test/Compatibility.java
/*
 * 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.curator.test;

import java.lang.reflect.Method;
import org.apache.zookeeper.server.ServerCnxn;
import org.apache.zookeeper.server.ServerCnxnFactory;

@SuppressWarnings({"unchecked", "rawtypes"})
public class Compatibility {
    private static final Method closeAllWithReasonMethod;
    private static final Method closeAllMethod;
    private static final Method closeWithReasonMethod;
    private static final Method closeMethod;
    private static final Object disconnectReasonObj;

    static {
        Object localDisconnectReasonObj;
        Method localCloseAllWithReasonMethod;
        Method localCloseAllMethod;
        Method localCloseWithReasonMethod;
        Method localCloseMethod;
        try {
            Class disconnectReasonClass = Class.forName("org.apache.zookeeper.server.ServerCnxn$DisconnectReason");
            localDisconnectReasonObj = Enum.valueOf(disconnectReasonClass, "UNKNOWN");
            localCloseAllWithReasonMethod =
                    ServerCnxnFactory.class.getDeclaredMethod("closeAll", disconnectReasonClass);
            localCloseWithReasonMethod = ServerCnxn.class.getDeclaredMethod("close", disconnectReasonClass);
            localCloseAllMethod = null;
            localCloseMethod = null;

            localCloseAllWithReasonMethod.setAccessible(true);
            localCloseWithReasonMethod.setAccessible(true);
        } catch (Throwable e) {
            localDisconnectReasonObj = null;
            localCloseAllWithReasonMethod = null;
            localCloseWithReasonMethod = null;
            try {
                localCloseAllMethod = ServerCnxnFactory.class.getDeclaredMethod("closeAll");
                localCloseMethod = ServerCnxn.class.getDeclaredMethod("close");

                localCloseAllMethod.setAccessible(true);
                localCloseMethod.setAccessible(true);
            } catch (Throwable ex) {
                throw new IllegalStateException(
                        "Could not reflectively find ServerCnxnFactory/ServerCnxn close methods");
            }
        }
        disconnectReasonObj = localDisconnectReasonObj;
        closeAllWithReasonMethod = localCloseAllWithReasonMethod;
        closeAllMethod = localCloseAllMethod;
        closeMethod = localCloseMethod;
        closeWithReasonMethod = localCloseWithReasonMethod;
    }

    public static void serverCnxnFactoryCloseAll(ServerCnxnFactory factory) {
        try {
            if (closeAllMethod != null) {
                closeAllMethod.invoke(factory);
            } else {
                closeAllWithReasonMethod.invoke(factory, disconnectReasonObj);
            }
        } catch (Exception e) {
            throw new RuntimeException("Could not close factory", e);
        }
    }

    public static void serverCnxnClose(ServerCnxn cnxn) {
        try {
            if (closeMethod != null) {
                closeMethod.invoke(cnxn);
            } else {
                closeWithReasonMethod.invoke(cnxn, disconnectReasonObj);
            }
        } catch (Exception e) {
            throw new RuntimeException("Could not close connection", e);
        }
    }
}
