com.streamsets.datacollector.activation.ActivationLoader.java Source code

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Here is the source code for com.streamsets.datacollector.activation.ActivationLoader.java

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/*
 * Copyright 2017 StreamSets 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.streamsets.datacollector.activation;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import com.streamsets.datacollector.main.RuntimeInfo;
import com.streamsets.pipeline.api.impl.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.List;
import java.util.ServiceLoader;
import java.util.concurrent.TimeUnit;

/**
 * Loads the Activation implementation if any is present, by default there is none.
 * <p/>
 * If there is no Activation implementation present it returns a NOP one.
 */
public class ActivationLoader {
    private final static Logger LOG = LoggerFactory.getLogger(ActivationLoader.class);
    private final RuntimeInfo runtimeInfo;

    public ActivationLoader(RuntimeInfo runtimeInfo) {
        this.runtimeInfo = runtimeInfo;
    }

    public Activation getActivation() {
        final Activation activation;
        ServiceLoader<Activation> serviceLoader = ServiceLoader.load(Activation.class);
        List<Activation> list = ImmutableList.copyOf(serviceLoader.iterator());
        if (list.isEmpty()) {
            activation = new NopActivation();
            LOG.debug("No activation service available, using {}", activation.getClass().getName());
        } else if (list.size() == 1) {
            activation = list.get(0);
            LOG.debug("Found activation service {}", activation.getClass().getName());
        } else {
            List<String> names = Lists.transform(list, element -> element.getClass().getName());
            throw new RuntimeException(Utils.format(
                    "There cannot be more than one Activation service, found '{}': {}", list.size(), names));
        }
        LOG.debug("Initializing");
        activation.init(runtimeInfo);
        LOG.debug("Initialized");
        if (activation.isEnabled()) {
            Activation.Info info = activation.getInfo();
            if (!info.isValid()) {
                LOG.info("Activation enabled, activation is not valid");
            } else if (info.getExpiration() == -1) {
                LOG.info("Activation enabled, activation is valid and it does not expire");
            } else {
                long daysToExpire = TimeUnit.MILLISECONDS.toDays(info.getExpiration() - System.currentTimeMillis());
                LOG.info("Activation enabled, activation is valid and it expires in '{}' days", daysToExpire);
            }
        } else {
            LOG.debug("Activation disabled");
        }
        return activation;
    }

}