https://projects.eclipse.org/projects/ee4j.jersey/jersey-common: Jersey core common packages (Eclipse Foundation) 
/*
 * Copyright (c) 2014, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey;

import jakarta.ws.rs.core.FeatureContext;
import jakarta.ws.rs.ext.ReaderInterceptorContext;
import jakarta.ws.rs.ext.WriterInterceptorContext;

import org.glassfish.jersey.internal.LocalizationMessages;
import org.glassfish.jersey.internal.inject.InjectionManager;
import org.glassfish.jersey.internal.inject.InjectionManagerSupplier;


Utility class with static methods that extract injection manager from various JAX-RS components. This class can be used when no injection is possible by Context or Inject annotation due to character of provider but there is a need to get any service from InjectionManager. 

Injections are not possible for example when a provider is registered as an instance on the client.
In this case the runtime will not inject the instance as this instance might be used in other client
runtimes too.




Example. This is the class using a standard injection:

    public static class MyWriterInterceptor implements WriterInterceptor {
        @Inject
        MyInjectedService service;
        @Override
        public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
            Something something = service.getSomething();
            ...
        }
    }






If this injection is not possible then this construct can be used:

    public static class MyWriterInterceptor implements WriterInterceptor {
        @Override
        public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
            InjectionManager injectionManager = InjectionManagerProvider.getInjectionManager(context);
            MyInjectedService service = injectionManager.getInstance(MyInjectedService.class);
            Something something = service.getSomething();
            ...
        }
    }






Note, that this injection support is intended mostly for injection of custom user types. JAX-RS types
are usually available without need for injections in method parameters. However, when injection of custom
type is needed it is preferred to use standard injections if it is possible rather than injection support
provided by this class.



 User returned InjectionManager only for purpose of getting services (do not change the state of the injection manager). 


Author:Miroslav Fuksa
Since:2.6
/**
 * Utility class with static methods that extract {@link InjectionManager injection manager}
 * from various JAX-RS components. This class can be used when no injection is possible by
 * {@link jakarta.ws.rs.core.Context} or {@link jakarta.inject.Inject} annotation due to character of
 * provider but there is a need to get any service from {@link InjectionManager}.
 * <p>
 * Injections are not possible for example when a provider is registered as an instance on the client.
 * In this case the runtime will not inject the instance as this instance might be used in other client
 * runtimes too.
 * </p>
 * <p>
 * Example. This is the class using a standard injection:
 * <pre>
 *     public static class MyWriterInterceptor implements WriterInterceptor {
 *         &#64;Inject
 *         MyInjectedService service;
 *
 *         &#64;Override
 *         public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
 *             Something something = service.getSomething();
 *             ...
 *         }
 *
 *     }
 * </pre>
 * </p>
 * <p>
 * If this injection is not possible then this construct can be used:
 * <pre>
 *     public static class MyWriterInterceptor implements WriterInterceptor {
 *
 *         &#64;Override
 *         public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
 *             InjectionManager injectionManager = InjectionManagerProvider.getInjectionManager(context);
 *             MyInjectedService service = injectionManager.getInstance(MyInjectedService.class);
 *             Something something = service.getSomething();
 *             ...
 *         }
 *     }
 * </pre>
 * </p>
 * <p>
 * Note, that this injection support is intended mostly for injection of custom user types. JAX-RS types
 * are usually available without need for injections in method parameters. However, when injection of custom
 * type is needed it is preferred to use standard injections if it is possible rather than injection support
 * provided by this class.
 * </p>
 * <p>
 * User returned {@code InjectionManager} only for purpose of getting services (do not change the state of the injection manager).
 * </p>
 *
 *
 * @author Miroslav Fuksa
 *
 * @since 2.6
 */
public class InjectionManagerProvider {

    
Extract and return injection manager from writerInterceptorContext. The method can be used to inject custom types into a WriterInterceptor. 
Params:
  • writerInterceptorContext – Writer interceptor context.
Throws:
Returns:injection manager.
/**
     * Extract and return injection manager from {@link jakarta.ws.rs.ext.WriterInterceptorContext writerInterceptorContext}.
     * The method can be used to inject custom types into a {@link jakarta.ws.rs.ext.WriterInterceptor}.
     *
     * @param writerInterceptorContext Writer interceptor context.
     *
     * @return injection manager.
     *
     * @throws java.lang.IllegalArgumentException when {@code writerInterceptorContext} is not a default
     * Jersey implementation provided by Jersey as argument in the
     * {@link jakarta.ws.rs.ext.WriterInterceptor#aroundWriteTo(jakarta.ws.rs.ext.WriterInterceptorContext)} method.
     */
    public static InjectionManager getInjectionManager(WriterInterceptorContext writerInterceptorContext) {
        if (!(writerInterceptorContext instanceof InjectionManagerSupplier)) {
            throw new IllegalArgumentException(
                    LocalizationMessages.ERROR_SERVICE_LOCATOR_PROVIDER_INSTANCE_FEATURE_WRITER_INTERCEPTOR_CONTEXT(
                            writerInterceptorContext.getClass().getName()));
        }
        return ((InjectionManagerSupplier) writerInterceptorContext).getInjectionManager();
    }

    
Extract and return injection manager from readerInterceptorContext. The method can be used to inject custom types into a ReaderInterceptor. 
Params:
  • readerInterceptorContext – Reader interceptor context.
Throws:
Returns:injection manager.
/**
     * Extract and return injection manager from {@link jakarta.ws.rs.ext.ReaderInterceptorContext readerInterceptorContext}.
     * The method can be used to inject custom types into a {@link jakarta.ws.rs.ext.ReaderInterceptor}.
     *
     * @param readerInterceptorContext Reader interceptor context.
     *
     * @return injection manager.
     *
     * @throws java.lang.IllegalArgumentException when {@code readerInterceptorContext} is not a default
     * Jersey implementation provided by Jersey as argument in the
     * {@link jakarta.ws.rs.ext.ReaderInterceptor#aroundReadFrom(jakarta.ws.rs.ext.ReaderInterceptorContext)} method.

     */
    public static InjectionManager getInjectionManager(ReaderInterceptorContext readerInterceptorContext) {
        if (!(readerInterceptorContext instanceof InjectionManagerSupplier)) {
            throw new IllegalArgumentException(
                    LocalizationMessages.ERROR_SERVICE_LOCATOR_PROVIDER_INSTANCE_FEATURE_READER_INTERCEPTOR_CONTEXT(
                            readerInterceptorContext.getClass().getName()));
        }
        return ((InjectionManagerSupplier) readerInterceptorContext).getInjectionManager();
    }

    
Extract and return injection manager from featureContext. The method can be used to inject custom types into a Feature. 

Note that features are utilized during initialization phase when not all providers are registered yet.
It is undefined which injections are already available in this phase.



Params:
  • featureContext – Feature context.
Throws:
Returns:injection manager.
/**
     * Extract and return injection manager from {@link jakarta.ws.rs.core.FeatureContext featureContext}.
     * The method can be used to inject custom types into a {@link jakarta.ws.rs.core.Feature}.
     * <p>
     * Note that features are utilized during initialization phase when not all providers are registered yet.
     * It is undefined which injections are already available in this phase.
     * </p>
     *
     * @param featureContext Feature context.
     *
     * @return injection manager.
     *
     * @throws java.lang.IllegalArgumentException when {@code writerInterceptorContext} is not a default
     * Jersey instance provided by Jersey
     * in {@link jakarta.ws.rs.core.Feature#configure(jakarta.ws.rs.core.FeatureContext)} method.
     */
    public static InjectionManager getInjectionManager(FeatureContext featureContext) {
        if (!(featureContext instanceof InjectionManagerSupplier)) {
            throw new IllegalArgumentException(
                    LocalizationMessages.ERROR_SERVICE_LOCATOR_PROVIDER_INSTANCE_FEATURE_CONTEXT(
                            featureContext.getClass().getName()));
        }
        return ((InjectionManagerSupplier) featureContext).getInjectionManager();
    }
}