io.nats.client.impl.NatsObjectStoreWatchSubscription Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jnats Show documentation
Client library for working with the NATS messaging system.
The newest version!
// Copyright 2022 The NATS Authors
// 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 io.nats.client.impl;

import io.nats.client.JetStreamApiException;
import io.nats.client.Message;
import io.nats.client.api.DeliverPolicy;
import io.nats.client.api.ObjectInfo;
import io.nats.client.api.ObjectStoreWatchOption;
import io.nats.client.api.ObjectStoreWatcher;

import java.io.IOException;
import java.util.Collections;

import static io.nats.client.api.ConsumerConfiguration.ULONG_UNSET;

public class NatsObjectStoreWatchSubscription extends NatsWatchSubscription {

    public NatsObjectStoreWatchSubscription(NatsObjectStore os, ObjectStoreWatcher watcher, ObjectStoreWatchOption... watchOptions) throws IOException, JetStreamApiException {
        super(os.js);

        // figure out the result options
        boolean headersOnly = false;
        boolean ignoreDeletes = false;
        DeliverPolicy deliverPolicy = DeliverPolicy.LastPerSubject;
        for (ObjectStoreWatchOption wo : watchOptions) {
            if (wo != null) {
                switch (wo) {
                    case IGNORE_DELETE: ignoreDeletes = true; break;
                    case UPDATES_ONLY: deliverPolicy = DeliverPolicy.New; break;
                    case INCLUDE_HISTORY: deliverPolicy = DeliverPolicy.All; break;
                }
            }
        }

        final boolean includeDeletes = !ignoreDeletes;
        WatchMessageHandler handler =
            new WatchMessageHandler(watcher) {
                @Override
                public void onMessage(Message m) throws InterruptedException {
                    ObjectInfo os = new ObjectInfo(m);
                    if (includeDeletes || !os.isDeleted()) {
                        watcher.watch(os);
                    }
                    if (!endOfDataSent && m.metaData().pendingCount() == 0) {
                        sendEndOfData();
                    }
                }
            };

        finishInit(os, Collections.singletonList(os.rawAllMetaSubject()), deliverPolicy, headersOnly, ULONG_UNSET, handler);
    }
}