org.eclipse.microprofile.context.spi.ContextManagerExtension Maven / Gradle / Ivy

Go to download
/*
 * Copyright (c) 2018,2019 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * 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.
 */
package org.eclipse.microprofile.context.spi;

/**
 * ContextManagerExtension instances receive
 * notification upon creation of each {@link ContextManager}.
 *
 * This serves as a convenient invocation point for enabling system wide
 * context propagator hooks.
 *
 * Implementations of ContextManagerExtension
 * and related classes are packaged within a third party JAR file, or they can
 * be supplied by the container or MicroProfile Context Propagation implementation.
 * ContextManagerExtensions are made discoverable
 * via the standard ServiceLoader mechanism. The JAR file that
 * packages it must include a file of the following name and location,
 *
 * META-INF/services/org.eclipse.microprofile.context.spi.ContextManagerExtension
 *
 * The content of the aforementioned file must be one or more lines, each
 * specifying the fully qualified name of a
 * ContextManagerExtension implementation that is
 * provided within the JAR file.
 *
 * Upon successful {@link ContextManager} creation, 
 * the MicroProfile Context Propagation implementation must subsequently query the container's
 * ServiceLoader for all
 * ContextManagerExtensions and call the
 * setup method on each instance.
 */
public interface ContextManagerExtension {
    /**
     * This method is called after every ContextManager
     * instance has been successfully created. Implementations may use
     * the supplied manager to create and configure builders and build
     * instances of ManagedExecutor and
     * ThreadContext. 
     *
     * @param manager the ContextManager instance that was
     *        just created. 
     */
    void setup(ContextManager manager);
}