curator-master/curator-framework/src/main/java/org/apache/curator/framework/imps/NamespaceWatcher.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.framework.imps;

import com.google.common.base.Objects;
import com.google.common.base.Preconditions;
import java.io.Closeable;
import org.apache.curator.framework.api.CuratorWatcher;
import org.apache.curator.utils.ThreadUtils;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;

class NamespaceWatcher implements Watcher, Closeable {
    private volatile CuratorFrameworkImpl client;
    private volatile Watcher actualWatcher;
    private final String unfixedPath;
    private volatile CuratorWatcher curatorWatcher;

    NamespaceWatcher(CuratorFrameworkImpl client, Watcher actualWatcher, String unfixedPath) {
        this.client = client;
        this.actualWatcher = actualWatcher;
        this.unfixedPath = Preconditions.checkNotNull(unfixedPath, "unfixedPath cannot be null");
        this.curatorWatcher = null;
    }

    NamespaceWatcher(CuratorFrameworkImpl client, CuratorWatcher curatorWatcher, String unfixedPath) {
        this.client = client;
        this.actualWatcher = null;
        this.curatorWatcher = curatorWatcher;
        this.unfixedPath = Preconditions.checkNotNull(unfixedPath, "unfixedPath cannot be null");
    }

    String getUnfixedPath() {
        return unfixedPath;
    }

    @Override
    public void close() {
        client = null;
        actualWatcher = null;
        curatorWatcher = null;
    }

    @Override
    public void process(WatchedEvent event) {
        if (client != null) {
            if ((event.getType() != Event.EventType.None) && (client.getWatcherRemovalManager() != null)) {
                client.getWatcherRemovalManager().noteTriggeredWatcher(this);
            }

            if (actualWatcher != null) {
                actualWatcher.process(new NamespaceWatchedEvent(client, event));
            } else if (curatorWatcher != null) {
                try {
                    curatorWatcher.process(new NamespaceWatchedEvent(client, event));
                } catch (Exception e) {
                    ThreadUtils.checkInterrupted(e);
                    client.logError("Watcher exception", e);
                }
            }
        }
    }

    /**
     * NamespaceWatcher should equal other wrappers that wrap the same instance.
     */
    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null) {
            return false;
        }

        if (getClass() == o.getClass()) {
            NamespaceWatcher watcher = (NamespaceWatcher) o;
            return Objects.equal(unfixedPath, watcher.getUnfixedPath())
                    && Objects.equal(actualWatcher, watcher.actualWatcher)
                    && Objects.equal(curatorWatcher, watcher.curatorWatcher);
        }

        return false;
    }

    @Override
    public int hashCode() {
        return Objects.hashCode(actualWatcher, unfixedPath, curatorWatcher);
    }
}
