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RxJava 3.x extra sources, operators and components and ports of many 1.x companion libraries.

There is a newer version: 3.1.1

/*
 * Copyright 2016-2019 David Karnok
 *
 * 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 hu.akarnokd.rxjava3.expr;

import java.util.Map;

import io.reactivex.rxjava3.core.*;
import io.reactivex.rxjava3.exceptions.Exceptions;
import io.reactivex.rxjava3.functions.Supplier;
import io.reactivex.rxjava3.internal.disposables.EmptyDisposable;

/**
 * For each Observer, it calls a keySelector for a key to lookup in the given Map for a MaybeSource
 * to subscribe to; otherwise subscribe the Observer to the default MaybeSource.
 *
 * @param  the output value type
 * @param  the key type
 */
final class MaybeSwitchCase extends Maybe {

    final Supplier caseSelector;

    final Map> mapOfCases;

    final MaybeSource defaultCase;

    MaybeSwitchCase(Supplier caseSelector,
                     Map> mapOfCases,
                     MaybeSource defaultCase) {
        this.caseSelector = caseSelector;
        this.mapOfCases = mapOfCases;
        this.defaultCase = defaultCase;
    }

    @Override
    protected void subscribeActual(MaybeObserver observer) {
        K key;
        MaybeSource source;

        try {
            key = caseSelector.get();

            source = mapOfCases.get(key);
        } catch (Throwable ex) {
            Exceptions.throwIfFatal(ex);
            EmptyDisposable.error(ex, observer);
            return;
        }

        if (source == null) {
            source = defaultCase;
        }

        source.subscribe(observer);
    }
}