/*
* 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.felix.framework.resolver;
import java.util.Comparator;
import org.apache.felix.framework.wiring.BundleCapabilityImpl;
import org.osgi.framework.Constants;
import org.osgi.framework.Version;
import org.osgi.framework.wiring.BundleCapability;
import org.osgi.framework.wiring.BundleRevision;
public class CandidateComparator implements Comparator<BundleCapability>
{
public int compare(BundleCapability cap1, BundleCapability cap2)
{
// First check resolved state, since resolved capabilities have priority
// over unresolved ones. Compare in reverse order since we want to sort
// in descending order.
int c = 0;
if ((cap1.getRevision().getWiring() != null)
&& (cap2.getRevision().getWiring() == null))
{
c = -1;
}
else if ((cap1.getRevision().getWiring() == null)
&& (cap2.getRevision().getWiring() != null))
{
c = 1;
}
// Compare revision capabilities.
if ((c == 0) && cap1.getNamespace().equals(BundleRevision.BUNDLE_NAMESPACE))
{
c = ((Comparable) cap1.getAttributes().get(BundleRevision.BUNDLE_NAMESPACE))
.compareTo(cap2.getAttributes().get(BundleRevision.BUNDLE_NAMESPACE));
if (c == 0)
{
Version v1 = (!cap1.getAttributes().containsKey(Constants.BUNDLE_VERSION_ATTRIBUTE))
? Version.emptyVersion
: (Version) cap1.getAttributes().get(Constants.BUNDLE_VERSION_ATTRIBUTE);
Version v2 = (!cap2.getAttributes().containsKey(Constants.BUNDLE_VERSION_ATTRIBUTE))
? Version.emptyVersion
: (Version) cap2.getAttributes().get(Constants.BUNDLE_VERSION_ATTRIBUTE);
// Compare these in reverse order, since we want
// highest version to have priority.
c = v2.compareTo(v1);
}
}
// Compare package capabilities.
else if ((c == 0) && cap1.getNamespace().equals(BundleRevision.PACKAGE_NAMESPACE))
{
c = ((Comparable) cap1.getAttributes().get(BundleRevision.PACKAGE_NAMESPACE))
.compareTo(cap2.getAttributes().get(BundleRevision.PACKAGE_NAMESPACE));
if (c == 0)
{
Version v1 = (!cap1.getAttributes().containsKey(BundleCapabilityImpl.VERSION_ATTR))
? Version.emptyVersion
: (Version) cap1.getAttributes().get(BundleCapabilityImpl.VERSION_ATTR);
Version v2 = (!cap2.getAttributes().containsKey(BundleCapabilityImpl.VERSION_ATTR))
? Version.emptyVersion
: (Version) cap2.getAttributes().get(BundleCapabilityImpl.VERSION_ATTR);
// Compare these in reverse order, since we want
// highest version to have priority.
c = v2.compareTo(v1);
}
}
// Finally, compare bundle identity.
if (c == 0)
{
if (cap1.getRevision().getBundle().getBundleId() <
cap2.getRevision().getBundle().getBundleId())
{
c = -1;
}
else if (cap1.getRevision().getBundle().getBundleId() >
cap2.getRevision().getBundle().getBundleId())
{
c = 1;
}
}
return c;
}
}