com.liferay.osgi.util.ComponentUtil.java Source code

Introduction

Here is the source code for com.liferay.osgi.util.ComponentUtil.java

Source

/**
 * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 */

package com.liferay.osgi.util;

import com.liferay.portal.kernel.util.StringBundler;
import com.liferay.portal.kernel.util.StringPool;
import com.liferay.portal.kernel.util.Validator;

import org.osgi.framework.ServiceReference;
import org.osgi.service.component.ComponentContext;
import org.osgi.util.tracker.ServiceTracker;
import org.osgi.util.tracker.ServiceTrackerCustomizer;

/**
 * @author Tina Tian
 */
public class ComponentUtil {

    public static <T> void enableComponents(Class<T> referenceClass, String filterString,
            ComponentContext componentContext, Class<?>... componentClasses) {

        AwaitReferenceServiceTrackerCustomizer<T> awaitReferenceServiceTrackerCustomizer = new AwaitReferenceServiceTrackerCustomizer<>(
                componentContext, componentClasses);

        ServiceTracker<T, T> serviceTracker = null;

        if (Validator.isNull(filterString)) {
            serviceTracker = ServiceTrackerFactory.create(componentContext.getBundleContext(), referenceClass,
                    awaitReferenceServiceTrackerCustomizer);
        } else {
            StringBundler sb = new StringBundler(5);

            sb.append("(&(objectClass=");
            sb.append(referenceClass.getName());
            sb.append(StringPool.CLOSE_PARENTHESIS);
            sb.append(filterString);
            sb.append(StringPool.CLOSE_PARENTHESIS);

            serviceTracker = ServiceTrackerFactory.create(componentContext.getBundleContext(), sb.toString(),
                    awaitReferenceServiceTrackerCustomizer);
        }

        awaitReferenceServiceTrackerCustomizer.setServiceTracker(serviceTracker);

        serviceTracker.open();
    }

    private static class AwaitReferenceServiceTrackerCustomizer<T> implements ServiceTrackerCustomizer<T, T> {

        @Override
        public T addingService(ServiceReference<T> serviceReference) {
            for (Class<?> componentClass : _componentClasses) {
                _componentContext.enableComponent(componentClass.getName());
            }

            _serviceTracker.close();

            return null;
        }

        @Override
        public void modifiedService(ServiceReference<T> serviceReference, T object) {
        }

        @Override
        public void removedService(ServiceReference<T> serviceReference, T object) {
        }

        public void setServiceTracker(ServiceTracker<T, T> serviceTracker) {
            _serviceTracker = serviceTracker;
        }

        private AwaitReferenceServiceTrackerCustomizer(ComponentContext componentContext,
                Class<?>[] componentClasses) {

            _componentContext = componentContext;
            _componentClasses = componentClasses;
        }

        private final Class<?>[] _componentClasses;
        private final ComponentContext _componentContext;
        private ServiceTracker<T, T> _serviceTracker;

    }

}