-
Notifications
You must be signed in to change notification settings - Fork 65
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Filter use-constraint violating providers of packages
If a provider is chosen for a given requirement this can imply that also other providers are now become invalid, currently the resolver simply checks the whole state and adds new permutations what is rather expensive. This now adds an additional local filtering step that checks for the chosen provider for the requirement and discards any incompatible provider for other packages in the same resource. As a result for a small testcase this saves 3 out of 23 (~ 10%) uses permutations.
- Loading branch information
Showing
4 changed files
with
339 additions
and
30 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
121 changes: 121 additions & 0 deletions
121
bundles/org.eclipse.osgi/felix/src/org/apache/felix/resolver/ProblemReduction.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,121 @@ | ||
| /* | ||
| * 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.resolver; | ||
|
|
||
| import java.util.ArrayList; | ||
| import java.util.Collections; | ||
| import java.util.List; | ||
| import java.util.Set; | ||
| import java.util.TreeSet; | ||
| import org.eclipse.osgi.container.ModuleContainer; | ||
| import org.osgi.framework.namespace.PackageNamespace; | ||
| import org.osgi.resource.Capability; | ||
| import org.osgi.resource.Requirement; | ||
| import org.osgi.resource.Resource; | ||
|
|
||
| /** | ||
| * The idea of the {@link ProblemReduction} class is to strike out | ||
| * {@link Capability}s that might satisfy {@link Requirement}s but violates some | ||
| * contracts that would lead to a guaranteed unresolvable state. | ||
| */ | ||
| class ProblemReduction { | ||
|
|
||
| private static final Capability[] EMPTY_CAPABILITIES = new Capability[0]; | ||
|
|
||
| private static final boolean DEBUG_VIOLATES = false; | ||
|
|
||
| /** | ||
| * Removes all violating providers for a given {@link Requirement} and | ||
| * {@link Candidates} in a local search, that is if the requirement has any uses | ||
| * it checks if there are other packages used by this one and removes any | ||
| * offending providers from the top of the list. | ||
| * | ||
| * @param candidates candidates to filter | ||
| * @param requirement the requirement where the search should start | ||
| * @return a list of Candidates that where dropped as part of the filtering | ||
| */ | ||
| static List<Candidates> removeUsesViolations(Candidates candidates, Requirement requirement) { | ||
| Resource targetResource = requirement.getResource(); | ||
| // fetch the current candidate for this requirement | ||
| Capability currentCandidate = candidates.getFirstCandidate(requirement); | ||
| Resource candidateResource = currentCandidate.getResource(); | ||
| // now check if it has any uses constraints | ||
| Set<String> uses = new TreeSet<>(Util.getUses(currentCandidate)); | ||
| if (uses.isEmpty()) { | ||
| // there is nothing this one can conflict in this current set of candidates | ||
| return Collections.emptyList(); | ||
| } | ||
| if (DEBUG_VIOLATES) { | ||
| System.out.println("=== remove uses violations for " + ModuleContainer.toString(requirement)); | ||
| System.out.println("== current candidate is " + ModuleContainer.toString(currentCandidate)); | ||
| candidates.dumpResource(targetResource, null, true, System.out); | ||
| } | ||
| boolean repeat; | ||
| int round = 0; | ||
| List<Candidates> dropped = new ArrayList<>(); | ||
| do { | ||
| repeat = false; | ||
| round++; | ||
| if (DEBUG_VIOLATES) { | ||
| System.out.println("Round " + round + ":"); | ||
| for (String usedPackage : uses) { | ||
| System.out.println(" uses: " + usedPackage); | ||
| } | ||
| } | ||
| // now look at all other imports of the target resource if it is a package that | ||
| // is part of a used package | ||
| for (Requirement packageRequirement : targetResource.getRequirements(PackageNamespace.PACKAGE_NAMESPACE)) { | ||
| if (packageRequirement == requirement) { | ||
| continue; | ||
| } | ||
| Capability providedPackage = candidates.getCapability(candidateResource, packageRequirement); | ||
| if (providedPackage == null) { | ||
| // we do not provide anything for this package | ||
| continue; | ||
| } | ||
| if (uses.contains(Util.getPackageName(providedPackage))) { | ||
| // this is a package where we are a candidate and that has a uses constraint, so | ||
| // this package must be provided by us as well or we run into a uses-violation | ||
| // later on! | ||
| Capability capability = removeViolators(candidates, candidateResource, packageRequirement, dropped); | ||
| // if we have added any additional uses we need to reiterate... | ||
| repeat |= uses.addAll(Util.getUses(capability)); | ||
| } | ||
| } | ||
| } while (repeat); | ||
| if (DEBUG_VIOLATES && !dropped.isEmpty()) { | ||
| System.out.println(); | ||
| System.out.println("After removal (" + dropped.size() + " dropped)"); | ||
| candidates.dumpResource(targetResource, null, true, System.out); | ||
| System.out.println(); | ||
| } | ||
| return dropped; | ||
| } | ||
|
|
||
| private static Capability removeViolators(Candidates candidates, Resource candidateResource, | ||
| Requirement packageRequirement, List<Candidates> dropped) { | ||
| Capability capability; | ||
| while ((capability = candidates.getFirstCandidate(packageRequirement)).getResource() != candidateResource) { | ||
| dropped.add(candidates.copy()); | ||
| candidates.removeFirstCandidate(packageRequirement); | ||
| } | ||
| return capability; | ||
| } | ||
|
|
||
| } |
Oops, something went wrong.