001/*
002 * Copyright 2002-2019 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.test.context;
018
019import org.springframework.context.ApplicationContext;
020import org.springframework.context.ConfigurableApplicationContext;
021import org.springframework.lang.Nullable;
022import org.springframework.test.annotation.DirtiesContext.HierarchyMode;
023
024/**
025 * A {@code CacheAwareContextLoaderDelegate} is responsible for {@linkplain
026 * #loadContext loading} and {@linkplain #closeContext closing} application
027 * contexts, interacting transparently with a
028 * {@link org.springframework.test.context.cache.ContextCache ContextCache}
029 * behind the scenes.
030 *
031 * <p>Note: {@code CacheAwareContextLoaderDelegate} does not extend the
032 * {@link ContextLoader} or {@link SmartContextLoader} interface.
033 *
034 * @author Sam Brannen
035 * @since 3.2.2
036 */
037public interface CacheAwareContextLoaderDelegate {
038
039        /**
040         * Determine if the {@linkplain ApplicationContext application context} for
041         * the supplied {@link MergedContextConfiguration} has been loaded (i.e.,
042         * is present in the {@code ContextCache}).
043         * <p>Implementations of this method <strong>must not</strong> load the
044         * application context as a side effect. In addition, implementations of
045         * this method should not log the cache statistics via
046         * {@link org.springframework.test.context.cache.ContextCache#logStatistics()}.
047         * <p>The default implementation of this method always returns {@code false}.
048         * Custom {@code CacheAwareContextLoaderDelegate} implementations are
049         * therefore highly encouraged to override this method with a more meaningful
050         * implementation. Note that the standard {@code CacheAwareContextLoaderDelegate}
051         * implementation in Spring overrides this method appropriately.
052         * @param mergedContextConfiguration the merged context configuration used
053         * to load the application context; never {@code null}
054         * @return {@code true} if the application context has been loaded
055         * @since 5.2
056         * @see #loadContext
057         * @see #closeContext
058         */
059        default boolean isContextLoaded(MergedContextConfiguration mergedContextConfiguration) {
060                return false;
061        }
062
063        /**
064         * Load the {@linkplain ApplicationContext application context} for the supplied
065         * {@link MergedContextConfiguration} by delegating to the {@link ContextLoader}
066         * configured in the given {@code MergedContextConfiguration}.
067         * <p>If the context is present in the {@code ContextCache} it will simply
068         * be returned; otherwise, it will be loaded, stored in the cache, and returned.
069         * <p>The cache statistics should be logged by invoking
070         * {@link org.springframework.test.context.cache.ContextCache#logStatistics()}.
071         * @param mergedContextConfiguration the merged context configuration to use
072         * to load the application context; never {@code null}
073         * @return the application context (never {@code null})
074         * @throws IllegalStateException if an error occurs while retrieving or loading
075         * the application context
076         * @see #isContextLoaded
077         * @see #closeContext
078         */
079        ApplicationContext loadContext(MergedContextConfiguration mergedContextConfiguration);
080
081        /**
082         * Remove the {@linkplain ApplicationContext application context} for the
083         * supplied {@link MergedContextConfiguration} from the {@code ContextCache}
084         * and {@linkplain ConfigurableApplicationContext#close() close} it if it is
085         * an instance of {@link ConfigurableApplicationContext}.
086         * <p>The semantics of the supplied {@code HierarchyMode} must be honored when
087         * removing the context from the cache. See the Javadoc for {@link HierarchyMode}
088         * for details.
089         * <p>Generally speaking, this method should only be called if the state of
090         * a singleton bean has been changed (potentially affecting future interaction
091         * with the context) or if the context needs to be prematurely removed from
092         * the cache.
093         * @param mergedContextConfiguration the merged context configuration for the
094         * application context to close; never {@code null}
095         * @param hierarchyMode the hierarchy mode; may be {@code null} if the context
096         * is not part of a hierarchy
097         * @since 4.1
098         * @see #isContextLoaded
099         * @see #loadContext
100         */
101        void closeContext(MergedContextConfiguration mergedContextConfiguration, @Nullable HierarchyMode hierarchyMode);
102
103}