| /******************************************************************************* |
| * Copyright (c) 2009, 2012 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.osgi.framework.console; |
| |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import org.osgi.framework.*; |
| |
| /** |
| * A console session service provides the input and output to a single console session. |
| * The input will be used by the console to read in console commands. The output will |
| * be used to print the results of console commands. |
| * <p> |
| * The console session must be registered as an OSGi service in order to be associated |
| * with a console instance. The console implementation will discover any console session |
| * services and will create a new console instance using the console session for input and |
| * output. When a session is closed then the console session service will be unregistered |
| * and the console instance will terminate and be disposed of. The console instance will |
| * also terminate if the console session service is unregistered for any reason. |
| * </p> |
| * @since 3.6 |
| */ |
| public abstract class ConsoleSession implements ServiceFactory<Object> { |
| private volatile ServiceRegistration<Object> sessionRegistration; |
| |
| /** |
| * Called by the console implementation to free resources associated |
| * with this console session. This method will result in the console |
| * session service being unregistered from the service registry. |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| public final void close() { |
| doClose(); |
| ServiceRegistration<Object> current = sessionRegistration; |
| if (current != null) { |
| sessionRegistration = null; |
| try { |
| current.unregister(); |
| } catch (IllegalStateException e) { |
| // This can happen if the service is in the process of being |
| // unregistered or if another thread unregistered the service. |
| // Ignoring the exception. |
| } |
| } |
| } |
| |
| /** |
| * Called by the {@link #close()} method to free resources associated |
| * with this console session. For example, closing the streams |
| * associated with the input and output for this session. |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| protected abstract void doClose(); |
| |
| /** |
| * Returns the input for this console session. This input will be used |
| * to read console commands from the user of the session. |
| * @return the input for this console session |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| public abstract InputStream getInput(); |
| |
| /** |
| * Returns the output for this console session. This output will be |
| * used to write the results of console commands. |
| * @return the output for this console session. |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| public abstract OutputStream getOutput(); |
| |
| /** |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| @Override |
| public final Object getService(Bundle bundle, ServiceRegistration<Object> registration) { |
| if (sessionRegistration == null) |
| sessionRegistration = registration; |
| return this; |
| } |
| |
| /** |
| * @noreference This method is not intended to be referenced by clients. |
| */ |
| @Override |
| public final void ungetService(Bundle bundle, ServiceRegistration<Object> registration, Object service) { |
| // do nothing |
| } |
| |
| } |