DefaultContextManager.java
- /*
- * *************************************************************************************************************************************************************
- *
- * TheseFoolishThings: Miscellaneous utilities
- * http://tidalwave.it/projects/thesefoolishthings
- *
- * Copyright (C) 2009 - 2024 by Tidalwave s.a.s. (http://tidalwave.it)
- *
- * *************************************************************************************************************************************************************
- *
- * 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.
- *
- * *************************************************************************************************************************************************************
- *
- * git clone https://bitbucket.org/tidalwave/thesefoolishthings-src
- * git clone https://github.com/tidalwave-it/thesefoolishthings-src
- *
- * *************************************************************************************************************************************************************
- */
- package it.tidalwave.role.impl;
- import javax.annotation.Nonnull;
- import java.util.ArrayList;
- import java.util.Collections;
- import java.util.List;
- import java.util.Optional;
- import java.util.Stack;
- import it.tidalwave.util.ContextManager;
- import lombok.extern.slf4j.Slf4j;
- import static it.tidalwave.util.CollectionUtils.reversed;
- import static it.tidalwave.util.ShortNames.*;
- /***************************************************************************************************************************************************************
- *
- * @author Fabrizio Giudici
- *
- **************************************************************************************************************************************************************/
- @Slf4j
- public class DefaultContextManager implements ContextManager
- {
- /** Useful for troubleshooting in cases when multiple instances are erroneously created. */
- private static final boolean DUMP_STACK_AT_CREATION = Boolean.getBoolean(
- DefaultContextManager.class.getName() + ".dumpStackAtCreation");
- /** The list of global contexts, ordered by priority. */
- private final List<Object> globalContexts = Collections.synchronizedList(new ArrayList<>());
- /** The list of local contexts, ordered by priority. */
- private final ThreadLocal<Stack<Object>> localContexts = new ThreadLocal<>()
- {
- @Override @Nonnull
- protected Stack<Object> initialValue ()
- {
- return new Stack<>();
- }
- };
- /***********************************************************************************************************************************************************
- *
- **********************************************************************************************************************************************************/
- public DefaultContextManager()
- {
- if (DUMP_STACK_AT_CREATION)
- {
- try
- {
- throw new RuntimeException();
- }
- catch (Exception e)
- {
- log.trace(">>>> created context manager " + this, e);
- }
- }
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override @Nonnull
- public List<Object> getContexts()
- {
- final var contexts = reversed(new ArrayList<>(localContexts.get()));
- contexts.addAll(0, globalContexts);
- return contexts;
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override @Nonnull @SuppressWarnings("BoundedWildcard")
- public <T> Optional<T> findContextOfType (@Nonnull final Class<T> contextType)
- {
- for (final var context : getContexts())
- {
- if (contextType.isAssignableFrom(context.getClass()))
- {
- return Optional.of(contextType.cast(context));
- }
- }
- return Optional.empty();
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override
- public void addGlobalContext (@Nonnull final Object context)
- {
- globalContexts.add(context);
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override
- public void removeGlobalContext (@Nonnull final Object context)
- {
- globalContexts.remove(context);
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override
- public void addLocalContext (@Nonnull final Object context)
- {
- localContexts.get().push(context);
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override
- public void removeLocalContext (@Nonnull final Object context)
- {
- localContexts.get().remove(context);
- }
- /***********************************************************************************************************************************************************
- * {@inheritDoc}
- **********************************************************************************************************************************************************/
- @Override @Nonnull
- public <T, E extends Throwable> T runEWithContexts (@Nonnull final SupplierWithException<T, E> supplier,
- @Nonnull final Object ... contexts)
- throws E
- {
- log.trace("runWithContexts({}, {})", shortId(supplier), shortIds(contexts));
- try (final var unused = binder(contexts))
- {
- if (log.isTraceEnabled())
- {
- log.trace(">>>> contexts now: {} - {}", shortIds(getContexts()), this);
- }
- final var result = supplier.get();
- log.trace(">>>> runWithContexts({}, {}) completed", shortId(supplier), shortIds(contexts));
- return result;
- }
- }
- }