com.twitter.heron.statemgr.zookeeper.ZkWatcherCallback.java Source code

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Here is the source code for com.twitter.heron.statemgr.zookeeper.ZkWatcherCallback.java

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// Copyright 2016 Twitter. All rights reserved.
//
// 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 com.twitter.heron.statemgr.zookeeper;

import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;

import com.twitter.heron.spi.statemgr.WatchCallback;

public final class ZkWatcherCallback {
    public static Watcher makeZkWatcher(final WatchCallback watcher) {
        return watcher == null ? null : new Watcher() {
            @Override
            public void process(WatchedEvent watchedEvent) {
                WatchCallback.WatchEventType watchEventType;
                switch (watchedEvent.getType()) {
                case None:
                    watchEventType = WatchCallback.WatchEventType.None;
                    break;
                case NodeCreated:
                    watchEventType = WatchCallback.WatchEventType.NodeCreated;
                    break;
                case NodeDeleted:
                    watchEventType = WatchCallback.WatchEventType.NodeDeleted;
                    break;
                case NodeDataChanged:
                    watchEventType = WatchCallback.WatchEventType.NodeDataChanged;
                    break;
                case NodeChildrenChanged:
                    watchEventType = WatchCallback.WatchEventType.NodeChildrenChanged;
                    break;

                default:
                    throw new RuntimeException("Invalid integer value for conversion to EventType");
                }
                watcher.processWatch(watchedEvent.getPath(), watchEventType);
            }
        };
    }

    private ZkWatcherCallback() {
    }
}