SimpleDomainEventPublisher.java

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package com.reallifedeveloper.common.domain.event;
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import java.util.ArrayList;
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import java.util.List;
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/**
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 * A publisher of domain events that holds subscribers in a list. Publishing is handled
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 * synchronously; to handle events asynchronously, a subscriber could send a message to
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 * a message queue or store the event for later processing.
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 * <p>
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 * The idea behind this publisher is that it will be configured once and for all, for
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 * example using Spring:
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 *
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 * <pre>
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 *   &lt;bean class="th.co.edge.domain.event.SimpleDomainEventPublisher"&gt;
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 *     &lt;constructor-arg&gt;
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 *       &lt;list&gt;
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 *         &lt;bean class="com.foo.FooSubscriber" /&gt;
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 *         &lt;bean class="com.foo.BarSubscriber" /&gt;
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 *       &lt;/list&gt;
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 *     &lt;/constructor-arg&gt;
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 *   &lt;/bean&gt;
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 * </pre>
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 * <p>
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 * The publisher can then be injected in the classes that need to publish events:
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 *
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 * <pre>
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 *   &#64;Autowired
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 *   private DomainEventSubscriber eventSubscriber;
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 * </pre>
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 * <p>
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 * Used this way in a normal enterprise application, several threads may call the
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 * {@link #publish(DomainEvent)} method simultaneously, so the subscribers should
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 * be thread safe.
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 *
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 * @author RealLifeDeveloper
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 */
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public final class SimpleDomainEventPublisher implements DomainEventPublisher {
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    private List<DomainEventSubscriber<? extends DomainEvent>> subscribers = new ArrayList<>();
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    /**
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     * Creates a new {@code SimpleDomainEventPublisher} with no subscribers registered.
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     * <p>
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     * Use the {@link #subscribe(DomainEventSubscriber)} to add subscribers.
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     */
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    public SimpleDomainEventPublisher() {
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        super();
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    }
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    /**
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     * Creates a new {@code SimpleDomainEventPublisher} with a number of subscribers
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     * registered to be notified when events are published.
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     *
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     * @param subscribers a list of subscribers to notify when events are published
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     * @throws IllegalArgumentException if {@code subscribers} is {@code null}
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     */
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    public SimpleDomainEventPublisher(List<DomainEventSubscriber<? extends DomainEvent>> subscribers) {
59 1 1. <init> : negated conditional → KILLED
 
        if (subscribers == null) {
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            throw new IllegalArgumentException("subscribers must not be null");
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        }
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        this.subscribers = new ArrayList<>(subscribers);
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    }
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    /**
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     * Publishes a domain event, i.e., calls the {@link DomainEventSubscriber#handleEvent(DomainEvent)}
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     * method for each registered subscriber.
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     *
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     * @param event the domain event to publish
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     * @throws IllegalArgumentException if {@code event} is {@code null}
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     */
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    @Override
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    public void publish(DomainEvent event) {
74 1 1. publish : negated conditional → KILLED
 
        if (event == null) {
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            throw new IllegalArgumentException("event must not be null");
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        }
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        for (DomainEventSubscriber<? extends DomainEvent> subscriber : subscribers) {
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            if (subscriber.eventType().isAssignableFrom(event.getClass())) {
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                @SuppressWarnings("unchecked")
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                DomainEventSubscriber<DomainEvent> s = (DomainEventSubscriber<DomainEvent>) subscriber;
81 1 1. publish : removed call to com/reallifedeveloper/common/domain/event/DomainEventSubscriber::handleEvent → KILLED
 
                s.handleEvent(event);
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            }
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        }
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    }
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    /**
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     * Registers an event handler with this publisher.
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     *
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     * @param subscriber the event handler to register
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     * @throws IllegalArgumentException if {@code subscriber} is {@code null}
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     */
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    @Override
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    public void subscribe(DomainEventSubscriber<? extends DomainEvent> subscriber) {
94 1 1. subscribe : negated conditional → KILLED
 
        if (subscriber == null) {
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            throw new IllegalArgumentException("subscriber must not be null");
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        }
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        subscribers.add(subscriber);
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    }
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}

Mutations

59

1.1
Location : <init>
Killed by : com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest.[engine:junit-jupiter]/[class:com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest]/[method:createPublisherWithNullSubscribers()] negated conditional → KILLED

74

1.1
Location : publish
Killed by : com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest.[engine:junit-jupiter]/[class:com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest]/[method:publishNullEvent()] negated conditional → KILLED

78

1.1
Location : publish
Killed by : com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest.[engine:junit-jupiter]/[class:com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest]/[method:publishWithSubscriber()] negated conditional → KILLED

81

1.1
Location : publish
Killed by : com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest.[engine:junit-jupiter]/[class:com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest]/[method:publishWithSubscriber()] removed call to com/reallifedeveloper/common/domain/event/DomainEventSubscriber::handleEvent → KILLED

94

1.1
Location : subscribe
Killed by : com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest.[engine:junit-jupiter]/[class:com.reallifedeveloper.common.domain.event.SimpleDomainEventPublisherTest]/[method:subscribeNullSubscriber()] negated conditional → KILLED

Active mutators

Tests examined


Report generated by PIT 1.20.0