code: /**
   * This file is part of Eclipse Steady.
   *
   * 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.
   *
   * SPDX-License-Identifier: Apache-2.0
   * SPDX-FileCopyrightText: Copyright (c) 2018-2020 SAP SE or an SAP affiliate company and Eclipse Steady contributors
   */
  package org.eclipse.steady.shared.cache;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  import org.junit.Test;
  
  public class CacheTest {
  
    @Test
    public void testWithMaxSize() {
      final Cache<String, String> cache =
          new Cache<String, String>(
              new ObjectFetcher<String, String>() {
                public String fetch(String _src) {
                  return _src + "-value";
                }
              },
              10,
              10);
  
      // Fill cache with 0-9
      for (int i = 0; i < 10; i++) {
        try {
          System.out.println(i + " -> " + cache.get(Integer.toString(i)));
        } catch (CacheException e) {
          e.printStackTrace();
          assertTrue(false);
        }
      }
  
      assertEquals(10, cache.getCacheRequest());
      assertEquals(0, cache.getCacheHit());
      assertEquals(10, cache.getCacheMiss());
      assertEquals(10, cache.getCacheFetch());
      assertEquals(0, cache.getCacheDelete());
  
      // Read 5-9, and fill 10-14 (thereby deleting 0-4)
      for (int i = 5; i < 15; i++) {
        try {
          System.out.println(i + " -> " + cache.get(Integer.toString(i)));
        } catch (CacheException e) {
          e.printStackTrace();
          assertTrue(false);
        }
      }
  
      assertEquals(20, cache.getCacheRequest());
      assertEquals(5, cache.getCacheHit());
      assertEquals(15, cache.getCacheMiss());
      assertEquals(15, cache.getCacheFetch());
      assertEquals(5, cache.getCacheDelete());
    }
  
    @Test
    public void testWithoutMaxSize() {
      final Cache<String, String> cache =
          new Cache<String, String>(
              new ObjectFetcher<String, String>() {
                public String fetch(String _src) {
                  return _src + "-value";
                }
              },
              10);
  
      // Fill cache with 0-9
      for (int i = 0; i < 10; i++) {
        try {
          System.out.println(i + " -> " + cache.get(Integer.toString(i)));
        } catch (CacheException e) {
          e.printStackTrace();
          assertTrue(false);
        }
      }
  
      assertEquals(10, cache.getCacheRequest());
      assertEquals(0, cache.getCacheHit());
      assertEquals(10, cache.getCacheMiss());
      assertEquals(10, cache.getCacheFetch());
      assertEquals(0, cache.getCacheDelete());
  
      // Read 5-9, and fill 10-14 (thereby deleting 0-4)
      for (int i = 5; i < 15; i++) {
        try {
          System.out.println(i + " -> " + cache.get(Integer.toString(i)));
        } catch (CacheException e) {
          e.printStackTrace();
          assertTrue(false);
        }
      }
  
      assertEquals(20, cache.getCacheRequest());
      assertEquals(5, cache.getCacheHit());
      assertEquals(15, cache.getCacheMiss());
      assertEquals(15, cache.getCacheFetch());
      assertEquals(0, cache.getCacheDelete()); // Only difference to testWithMaxSize()
    }
  
    @Test(expected = IllegalArgumentException.class)
    public void testIllegalMaxSize() {
      @SuppressWarnings("unused")
      final Cache<String, String> cache =
          new Cache<String, String>(
              new ObjectFetcher<String, String>() {
                public String fetch(String _src) {
                  return _src + "-value";
                }
              },
              10,
              0);
    }
  
    @Test(expected = IllegalArgumentException.class)
    public void testIllegalFetcher() {
      @SuppressWarnings("unused")
      final Cache<String, String> cache = new Cache<String, String>(null, 10, 10);
    }
  
    @Test(expected = IllegalArgumentException.class)
    public void testIllegalRefresh() {
      @SuppressWarnings("unused")
      final Cache<String, String> cache =
          new Cache<String, String>(
              new ObjectFetcher<String, String>() {
                public String fetch(String _src) {
                  return _src + "-value";
                }
              },
              -1,
              10);
    }
  }
  