src/main/java/org/apache/sling/installer/core/impl/util/PABundleRefresher.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.sling.installer.core.impl.util;

import java.util.List;

import org.apache.sling.installer.api.tasks.InstallationContext;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleContext;
import org.osgi.framework.FrameworkEvent;
import org.osgi.framework.FrameworkListener;
import org.osgi.service.packageadmin.PackageAdmin;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Implementation using the package admin
 */
public class PABundleRefresher implements BundleRefresher, FrameworkListener {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    /** Max time allowed to refresh packages */
    private static final int MAX_REFRESH_PACKAGES_WAIT_SECONDS = 90;

    /** Counter for package refresh events. */
    private volatile long refreshEventCount;

    private final PackageAdmin pckAdmin;
    private final RefreshDependenciesUtil rdu;
    private final BundleContext bundleContext;

    /** Lock object for syncing. */
    private  final Object lock = new Object();

    public PABundleRefresher(final PackageAdmin pa, final BundleContext bundleContext) {
        this.pckAdmin = pa;
        this.bundleContext = bundleContext;
        this.rdu = new RefreshDependenciesUtil(pa);
    }

    /**
     * @see org.apache.sling.installer.core.impl.util.BundleRefresher#refreshBundles(org.apache.sling.installer.api.tasks.InstallationContext, java.util.List, boolean)
     */
    public void refreshBundles(final InstallationContext ctx,
                               final List<Bundle> bundles,
                               final boolean wait) {
        if ( bundles == null || bundles.size() > 0 ) {
            if ( bundles == null ) {
                ctx.log("Full package refreshing");
            } else {
                ctx.log("Refreshing {} bundles: {}", bundles.size(), bundles);
            }
            if ( !wait ) {
                this.pckAdmin.refreshPackages(bundles == null ? null : bundles.toArray(new Bundle[bundles.size()]));
            } else {
                this.refreshEventCount = -1;
                this.bundleContext.addFrameworkListener(this);
                try {
                    this.refreshEventCount = 0;
                    this.pckAdmin.refreshPackages(bundles == null ? null : bundles.toArray(new Bundle[bundles.size()]));
                    final long end = System.currentTimeMillis() + (MAX_REFRESH_PACKAGES_WAIT_SECONDS * 1000);
                    do {
                        synchronized ( this.lock ) {
                            final long waitTime = end - System.currentTimeMillis();
                            if ( this.refreshEventCount < 1 && waitTime > 0 ) {
                                try {
                                    ctx.log("Waiting up to {} seconds for bundles refresh", MAX_REFRESH_PACKAGES_WAIT_SECONDS);
                                    this.lock.wait(waitTime);
                                } catch (final InterruptedException ignore) {
                                    // ignore
                                }
                                if ( end <= System.currentTimeMillis() && this.refreshEventCount < 1 ) {
                                    logger.warn("No FrameworkEvent.PACKAGES_REFRESHED event received within {}"
                                                    + " seconds after refresh, aborting wait.",
                                                    MAX_REFRESH_PACKAGES_WAIT_SECONDS);
                                    this.refreshEventCount++;
                                }
                            }
                        }
                    } while ( this.refreshEventCount < 1);
                } finally {
                    this.bundleContext.removeFrameworkListener(this);
                }
            }
            if ( bundles == null ) {
                ctx.log("Done full package refresh");
            } else {
                ctx.log("Done refreshing {} bundles", bundles.size());
            }
        }
    }

    /**
     * Check whether a bundle refresh would affect the installer bundle
     * @see org.apache.sling.installer.core.impl.util.BundleRefresher#isInstallerBundleAffected(java.util.List)
     */
    public boolean isInstallerBundleAffected(final List<Bundle> bundles) {
        return rdu.isBundleAffected(bundleContext.getBundle(), bundles);
    }

    /**
     * @see org.osgi.framework.FrameworkListener#frameworkEvent(org.osgi.framework.FrameworkEvent)
     */
    public void frameworkEvent(final FrameworkEvent event) {
        if (event.getType() == FrameworkEvent.PACKAGES_REFRESHED) {
            logger.debug("FrameworkEvent.PACKAGES_REFRESHED");
            synchronized (this.lock) {
                this.refreshEventCount++;
                this.lock.notify();
            }
        }
    }
}