com.netflix.curator.framework.imps.CuratorTempFrameworkImpl.java Source code

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Here is the source code for com.netflix.curator.framework.imps.CuratorTempFrameworkImpl.java

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/*
 * Copyright 2013 Netflix, Inc.
 *
 *    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.netflix.curator.framework.imps;

import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;

import org.apache.commons.io.IOUtils;

import com.google.common.annotations.VisibleForTesting;
import com.netflix.curator.framework.CuratorFrameworkFactory;
import com.netflix.curator.framework.CuratorTempFramework;
import com.netflix.curator.framework.api.TempGetDataBuilder;
import com.netflix.curator.framework.api.transaction.CuratorTransaction;

public class CuratorTempFrameworkImpl implements CuratorTempFramework {
    private final CuratorFrameworkFactory.Builder factory;
    private final long inactiveThresholdMs;

    // guarded by sync
    private CuratorFrameworkImpl client;

    // guarded by sync
    private ScheduledExecutorService cleanup;

    // guarded by sync
    private long lastAccess;

    public CuratorTempFrameworkImpl(CuratorFrameworkFactory.Builder factory, long inactiveThresholdMs) {
        this.factory = factory;
        this.inactiveThresholdMs = inactiveThresholdMs;
    }

    @Override
    public void close() {
        closeClient();
    }

    @Override
    public CuratorTransaction inTransaction() throws Exception {
        openConnectionIfNeeded();
        return new CuratorTransactionImpl(client);
    }

    @Override
    public TempGetDataBuilder getData() throws Exception {
        openConnectionIfNeeded();
        return new TempGetDataBuilderImpl(client);
    }

    @VisibleForTesting
    CuratorFrameworkImpl getClient() {
        return client;
    }

    @VisibleForTesting
    ScheduledExecutorService getCleanup() {
        return cleanup;
    }

    @VisibleForTesting
    synchronized void updateLastAccess() {
        lastAccess = System.currentTimeMillis();
    }

    private synchronized void openConnectionIfNeeded() throws Exception {
        if (client == null) {
            client = (CuratorFrameworkImpl) factory.build(); // cast is safe - we control both sides of this
            client.start();
        }

        if (cleanup == null) {
            ThreadFactory threadFactory = factory.getThreadFactory();
            cleanup = (threadFactory != null) ? Executors.newScheduledThreadPool(1, threadFactory)
                    : Executors.newScheduledThreadPool(1);

            Runnable command = new Runnable() {
                @Override
                public void run() {
                    checkInactive();
                }
            };
            cleanup.scheduleAtFixedRate(command, inactiveThresholdMs, inactiveThresholdMs, TimeUnit.MILLISECONDS);
        }

        updateLastAccess();
    }

    private synchronized void checkInactive() {
        long elapsed = System.currentTimeMillis() - lastAccess;
        if (elapsed >= inactiveThresholdMs) {
            closeClient();
        }
    }

    private synchronized void closeClient() {
        if (cleanup != null) {
            cleanup.shutdownNow();
            cleanup = null;
        }

        if (client != null) {
            IOUtils.closeQuietly(client);
            client = null;
        }
    }
}