foundations/foundation-common/src/test/java/org/apache/servicecomb/foundation/common/event/TestEventManager.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.servicecomb.foundation.common.event;

import org.apache.servicecomb.foundation.test.scaffolding.log.LogCollector;

import com.google.common.eventbus.Subscribe;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

public class TestEventManager {
  private int objCount = 0;

  private int iCount = 0;

  public void test(Object listener) {
    EventManager.register(listener);
    EventManager.post("a");
    EventManager.post(1);
    Assertions.assertEquals(2, objCount);
    Assertions.assertEquals(1, iCount);

    EventManager.unregister(listener);
    EventManager.post("a");
    EventManager.post(1);
    Assertions.assertEquals(2, objCount);
    Assertions.assertEquals(1, iCount);
  }

  @Test
  public void normalListener() {
    LogCollector collector = new LogCollector();

    test(this);
    Assertions.assertTrue(collector.getEvents().isEmpty()); // ensure no warning logs
    collector.teardown();
  }

  @Test
  public void anonymousListener() {
    LogCollector collector = new LogCollector();
    Object listener = new Object() {
      @Subscribe
      private void onObject(Object obj) {
        objCount++;
      }

      @Subscribe
      void onInt(Integer obj) {
        iCount++;
      }
    };
    try {
      test(listener);
      Assertions.fail();
    } catch (IllegalStateException e) {
      Assertions.assertTrue(true);
    }

    collector.teardown();
  }

  @Test
  public void anonymousListenerPublic() {
    LogCollector collector = new LogCollector();
    Object listener = new Object() {
      @Subscribe
      public void onObject(Object obj) {
        objCount++;
      }

      @Subscribe
      public void onInt(Integer obj) {
        iCount++;
      }
    };
    try {
      test(listener);
      Assertions.fail();
    } catch (IllegalStateException e) {
      Assertions.assertTrue(true);
    }

    // ensure logs: "LOGGER.warn("Failed to create lambda for method: {}, fallback to reflect.", method, throwable);"
    Assertions.assertFalse(collector.getEvents().isEmpty());
    collector.teardown();
  }

  @Subscribe
  public void onObject(Object obj) {
    objCount++;
  }

  @Subscribe
  public void onInt(Integer obj) {
    iCount++;
  }
}