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Posted to commits@aries.apache.org by jw...@apache.org on 2012/04/22 21:49:22 UTC
svn commit: r1328953 [2/4] - in
/aries/trunk/subsystem/subsystem-core/src/main/java/org/apache:
aries/subsystem/core/ aries/subsystem/core/archive/
aries/subsystem/core/internal/ aries/subsystem/core/resource/
aries/subsystem/core/resource/tmp/ felix/r...
Added: aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/felix/resolver/Candidates.java
URL: http://svn.apache.org/viewvc/aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/felix/resolver/Candidates.java?rev=1328953&view=auto
==============================================================================
--- aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/felix/resolver/Candidates.java (added)
+++ aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/felix/resolver/Candidates.java Sun Apr 22 19:49:20 2012
@@ -0,0 +1,1052 @@
+/*
+ * 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.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.TreeMap;
+import org.osgi.framework.Version;
+import org.osgi.framework.namespace.HostNamespace;
+import org.osgi.framework.namespace.PackageNamespace;
+import org.osgi.resource.Capability;
+import org.osgi.resource.Requirement;
+import org.osgi.resource.Resource;
+import org.osgi.resource.Wire;
+import org.osgi.resource.Wiring;
+import org.osgi.service.resolver.HostedCapability;
+import org.osgi.service.resolver.ResolutionException;
+import org.osgi.service.resolver.ResolveContext;
+
+class Candidates
+{
+ public static final int MANDATORY = 0;
+ public static final int OPTIONAL = 1;
+ public static final int ON_DEMAND = 2;
+
+ private final Set<Resource> m_mandatoryResources;
+ // Maps a capability to requirements that match it.
+ private final Map<Capability, Set<Requirement>> m_dependentMap;
+ // Maps a requirement to the capability it matches.
+ private final Map<Requirement, List<Capability>> m_candidateMap;
+ // Maps a bundle revision to its associated wrapped revision; this only happens
+ // when a revision being resolved has fragments to attach to it.
+ private final Map<Resource, WrappedResource> m_allWrappedHosts;
+ // Map used when populating candidates to hold intermediate and final results.
+ private final Map<Resource, Object> m_populateResultCache;
+
+ // Flag to signal if fragments are present in the candidate map.
+ private boolean m_fragmentsPresent = false;
+
+ /**
+ * Private copy constructor used by the copy() method.
+ * @param dependentMap the capability dependency map.
+ * @param candidateMap the requirement candidate map.
+ * @param hostFragments the fragment map.
+ * @param wrappedHosts the wrapped hosts map.
+ **/
+ private Candidates(
+ Set<Resource> mandatoryResources,
+ Map<Capability, Set<Requirement>> dependentMap,
+ Map<Requirement, List<Capability>> candidateMap,
+ Map<Resource, WrappedResource> wrappedHosts, Map<Resource, Object> populateResultCache,
+ boolean fragmentsPresent)
+ {
+ m_mandatoryResources = mandatoryResources;
+ m_dependentMap = dependentMap;
+ m_candidateMap = candidateMap;
+ m_allWrappedHosts = wrappedHosts;
+ m_populateResultCache = populateResultCache;
+ m_fragmentsPresent = fragmentsPresent;
+ }
+
+ /**
+ * Constructs an empty Candidates object.
+ **/
+ public Candidates()
+ {
+ m_mandatoryResources = new HashSet<Resource>();
+ m_dependentMap = new HashMap<Capability, Set<Requirement>>();
+ m_candidateMap = new HashMap<Requirement, List<Capability>>();
+ m_allWrappedHosts = new HashMap<Resource, WrappedResource>();
+ m_populateResultCache = new HashMap<Resource, Object>();
+ }
+
+ /**
+ * Populates candidates for the specified revision. How a revision is
+ * resolved depends on its resolution type as follows:
+ * <ul>
+ * <li><tt>MANDATORY</tt> - must resolve and failure to do so throws
+ * an exception.</li>
+ * <li><tt>OPTIONAL</tt> - attempt to resolve, but no exception is thrown
+ * if the resolve fails.</li>
+ * <li><tt>ON_DEMAND</tt> - only resolve on demand; this only applies to
+ * fragments and will only resolve a fragment if its host is already
+ * selected as a candidate.</li>
+ * </ul>
+ * @param state the resolver state used for populating the candidates.
+ * @param revision the revision whose candidates should be populated.
+ * @param resolution indicates the resolution type.
+ */
+ public final void populate(
+ ResolveContext rc, Resource resource, int resolution) throws ResolutionException
+ {
+ // Get the current result cache value, to make sure the revision
+ // hasn't already been populated.
+ Object cacheValue = m_populateResultCache.get(resource);
+ // Has been unsuccessfully populated.
+ if (cacheValue instanceof ResolutionException)
+ {
+ return;
+ }
+ // Has been successfully populated.
+ else if (cacheValue instanceof Boolean)
+ {
+ return;
+ }
+
+ // We will always attempt to populate fragments, since this is necessary
+ // for ondemand attaching of fragment. However, we'll only attempt to
+ // populate optional non-fragment revisions if they aren't already
+ // resolved.
+ boolean isFragment = Util.isFragment(resource);
+ if (!isFragment && rc.getWirings().containsKey(resource))
+ {
+ return;
+ }
+
+ // Always attempt to populate mandatory or optional revisions.
+ // However, for on-demand fragments only populate if their host
+ // is already populated.
+ if ((resolution != ON_DEMAND)
+ || (isFragment && populateFragmentOndemand(rc, resource)))
+ {
+ if (resolution == MANDATORY)
+ {
+ m_mandatoryResources.add(resource);
+ }
+ try
+ {
+ // Try to populate candidates for the optional revision.
+ populateResource(rc, resource);
+ }
+ catch (ResolutionException ex)
+ {
+ // Only throw an exception if resolution is mandatory.
+ if (resolution == MANDATORY)
+ {
+ throw ex;
+ }
+ }
+ }
+ }
+
+ /**
+ * Populates candidates for the specified revision.
+ * @param state the resolver state used for populating the candidates.
+ * @param revision the revision whose candidates should be populated.
+ */
+// TODO: FELIX3 - Modify to not be recursive.
+ private void populateResource(ResolveContext rc, Resource resource) throws ResolutionException
+ {
+ // Determine if we've already calculated this revision's candidates.
+ // The result cache will have one of three values:
+ // 1. A resolve exception if we've already attempted to populate the
+ // revision's candidates but were unsuccessful.
+ // 2. Boolean.TRUE indicating we've already attempted to populate the
+ // revision's candidates and were successful.
+ // 3. An array containing the cycle count, current map of candidates
+ // for already processed requirements, and a list of remaining
+ // requirements whose candidates still need to be calculated.
+ // For case 1, rethrow the exception. For case 2, simply return immediately.
+ // For case 3, this means we have a cycle so we should continue to populate
+ // the candidates where we left off and not record any results globally
+ // until we've popped completely out of the cycle.
+
+ // Keeps track of the number of times we've reentered this method
+ // for the current revision.
+ Integer cycleCount = null;
+
+ // Keeps track of the candidates we've already calculated for the
+ // current revision's requirements.
+ Map<Requirement, List<Capability>> localCandidateMap = null;
+
+ // Keeps track of the current revision's requirements for which we
+ // haven't yet found candidates.
+ List<Requirement> remainingReqs = null;
+
+ // Get the cache value for the current revision.
+ Object cacheValue = m_populateResultCache.get(resource);
+
+ // This is case 1.
+ if (cacheValue instanceof ResolutionException)
+ {
+ throw (ResolutionException) cacheValue;
+ }
+ // This is case 2.
+ else if (cacheValue instanceof Boolean)
+ {
+ return;
+ }
+ // This is case 3.
+ else if (cacheValue != null)
+ {
+ // Increment and get the cycle count.
+ cycleCount = (Integer)
+ (((Object[]) cacheValue)[0]
+ = new Integer(((Integer) ((Object[]) cacheValue)[0]).intValue() + 1));
+ // Get the already populated candidates.
+ localCandidateMap = (Map) ((Object[]) cacheValue)[1];
+ // Get the remaining requirements.
+ remainingReqs = (List) ((Object[]) cacheValue)[2];
+ }
+
+ // If there is no cache value for the current revision, then this is
+ // the first time we are attempting to populate its candidates, so
+ // do some one-time checks and initialization.
+ if ((remainingReqs == null) && (localCandidateMap == null))
+ {
+ // Record cycle count.
+ cycleCount = new Integer(0);
+
+ // Create a local map for populating candidates first, just in case
+ // the revision is not resolvable.
+ localCandidateMap = new HashMap();
+
+ // Create a modifiable list of the revision's requirements.
+ remainingReqs = new ArrayList(resource.getRequirements(null));
+
+ // Add these value to the result cache so we know we are
+ // in the middle of populating candidates for the current
+ // revision.
+ m_populateResultCache.put(resource,
+ cacheValue = new Object[] { cycleCount, localCandidateMap, remainingReqs });
+ }
+
+ // If we have requirements remaining, then find candidates for them.
+ while (!remainingReqs.isEmpty())
+ {
+ Requirement req = remainingReqs.remove(0);
+
+ // Ignore non-effective and dynamic requirements.
+ String resolution = req.getDirectives()
+ .get(PackageNamespace.REQUIREMENT_RESOLUTION_DIRECTIVE);
+ if (!rc.isEffective(req)
+ || ((resolution != null)
+ && resolution.equals(PackageNamespace.RESOLUTION_DYNAMIC)))
+ {
+ continue;
+ }
+
+ // Process the candidates, removing any candidates that
+ // cannot resolve.
+ List<Capability> candidates = rc.findProviders(req);
+ ResolutionException rethrow = processCandidates(rc, resource, candidates);
+
+ // First, due to cycles, makes sure we haven't already failed in
+ // a deeper recursion.
+ Object result = m_populateResultCache.get(resource);
+ if (result instanceof ResolutionException)
+ {
+ throw (ResolutionException) result;
+ }
+ // Next, if are no candidates remaining and the requirement is not
+ // not optional, then record and throw a resolve exception.
+ else if (candidates.isEmpty() && !Util.isOptional(req))
+ {
+ String msg = "Unable to resolve " + resource
+ + ": missing requirement " + req;
+ if (rethrow != null)
+ {
+ msg = msg + " [caused by: " + rethrow.getMessage() + "]";
+ }
+ rethrow = new ResolutionException(msg, null, Collections.singleton(req));
+ m_populateResultCache.put(resource, rethrow);
+ throw rethrow;
+ }
+ // Otherwise, if we actually have candidates for the requirement, then
+ // add them to the local candidate map.
+ else if (candidates.size() > 0)
+ {
+ localCandidateMap.put(req, candidates);
+ }
+ }
+
+ // If we are exiting from a cycle then decrement
+ // cycle counter, otherwise record the result.
+ if (cycleCount.intValue() > 0)
+ {
+ ((Object[]) cacheValue)[0] = new Integer(cycleCount.intValue() - 1);
+ }
+ else if (cycleCount.intValue() == 0)
+ {
+ // Record that the revision was successfully populated.
+ m_populateResultCache.put(resource, Boolean.TRUE);
+
+ // Merge local candidate map into global candidate map.
+ if (localCandidateMap.size() > 0)
+ {
+ add(localCandidateMap);
+ }
+ }
+ }
+
+ private boolean populateFragmentOndemand(ResolveContext rc, Resource resource)
+ throws ResolutionException
+ {
+ // Create a modifiable list of the revision's requirements.
+ List<Requirement> remainingReqs =
+ new ArrayList(resource.getRequirements(null));
+ // Find the host requirement.
+ Requirement hostReq = null;
+ for (Iterator<Requirement> it = remainingReqs.iterator();
+ it.hasNext(); )
+ {
+ Requirement r = it.next();
+ if (r.getNamespace().equals(HostNamespace.HOST_NAMESPACE))
+ {
+ hostReq = r;
+ it.remove();
+ break;
+ }
+ }
+ // Get candidates hosts and keep any that have been populated.
+ List<Capability> hosts = rc.findProviders(hostReq);
+ for (Iterator<Capability> it = hosts.iterator(); it.hasNext(); )
+ {
+ Capability host = it.next();
+ if (!isPopulated(host.getResource()))
+ {
+ it.remove();
+ }
+ }
+ // If there aren't any populated hosts, then we can just
+ // return since this fragment isn't needed.
+ if (hosts.isEmpty())
+ {
+ return false;
+ }
+
+ // If there are populated host candidates, then prepopulate
+ // the result cache with the work we've done so far.
+ // Record cycle count, but start at -1 since it will
+ // be incremented again in populate().
+ Integer cycleCount = new Integer(-1);
+ // Create a local map for populating candidates first, just in case
+ // the revision is not resolvable.
+ Map<Requirement, List<Capability>> localCandidateMap =
+ new HashMap<Requirement, List<Capability>>();
+ // Add the discovered host candidates to the local candidate map.
+ localCandidateMap.put(hostReq, hosts);
+ // Add these value to the result cache so we know we are
+ // in the middle of populating candidates for the current
+ // revision.
+ m_populateResultCache.put(resource,
+ new Object[] { cycleCount, localCandidateMap, remainingReqs });
+ return true;
+ }
+
+ public void populateDynamic(
+ ResolveContext rc, Resource resource,
+ Requirement req, List<Capability> candidates) throws ResolutionException
+ {
+ // Record the revision associated with the dynamic require
+ // as a mandatory revision.
+ m_mandatoryResources.add(resource);
+
+ // Add the dynamic imports candidates.
+ add(req, candidates);
+
+ // Process the candidates, removing any candidates that
+ // cannot resolve.
+ ResolutionException rethrow = processCandidates(rc, resource, candidates);
+
+ if (candidates.isEmpty())
+ {
+ if (rethrow == null)
+ {
+ rethrow = new ResolutionException(
+ "Dynamic import failed.", null, Collections.singleton(req));
+ }
+ throw rethrow;
+ }
+
+ m_populateResultCache.put(resource, Boolean.TRUE);
+ }
+
+ /**
+ * This method performs common processing on the given set of candidates.
+ * Specifically, it removes any candidates which cannot resolve and it
+ * synthesizes candidates for any candidates coming from any attached
+ * fragments, since fragment capabilities only appear once, but technically
+ * each host represents a unique capability.
+ * @param state the resolver state.
+ * @param revision the revision being resolved.
+ * @param candidates the candidates to process.
+ * @return a resolve exception to be re-thrown, if any, or null.
+ */
+ private ResolutionException processCandidates(
+ ResolveContext rc,
+ Resource resource,
+ List<Capability> candidates)
+ {
+ // Get satisfying candidates and populate their candidates if necessary.
+ ResolutionException rethrow = null;
+ Set<Capability> fragmentCands = null;
+ for (Iterator<Capability> itCandCap = candidates.iterator();
+ itCandCap.hasNext(); )
+ {
+ Capability candCap = itCandCap.next();
+
+ boolean isFragment = Util.isFragment(candCap.getResource());
+
+ // If the capability is from a fragment, then record it
+ // because we have to insert associated host capabilities
+ // if the fragment is already attached to any hosts.
+ if (isFragment)
+ {
+ if (fragmentCands == null)
+ {
+ fragmentCands = new HashSet<Capability>();
+ }
+ fragmentCands.add(candCap);
+ }
+
+ // If the candidate revision is a fragment, then always attempt
+ // to populate candidates for its dependency, since it must be
+ // attached to a host to be used. Otherwise, if the candidate
+ // revision is not already resolved and is not the current version
+ // we are trying to populate, then populate the candidates for
+ // its dependencies as well.
+ // NOTE: Technically, we don't have to check to see if the
+ // candidate revision is equal to the current revision, but this
+ // saves us from recursing and also simplifies exceptions messages
+ // since we effectively chain exception messages for each level
+ // of recursion; thus, any avoided recursion results in fewer
+ // exceptions to chain when an error does occur.
+ if ((isFragment || !rc.getWirings().containsKey(candCap.getResource()))
+ && !candCap.getResource().equals(resource))
+ {
+ try
+ {
+ populateResource(rc, candCap.getResource());
+ }
+ catch (ResolutionException ex)
+ {
+ if (rethrow == null)
+ {
+ rethrow = ex;
+ }
+ // Remove the candidate since we weren't able to
+ // populate its candidates.
+ itCandCap.remove();
+ }
+ }
+ }
+
+ // If any of the candidates for the requirement were from a fragment,
+ // then also insert synthesized hosted capabilities for any other host
+ // to which the fragment is attached since they are all effectively
+ // unique capabilities.
+ if (fragmentCands != null)
+ {
+ for (Capability fragCand : fragmentCands)
+ {
+ // Only necessary for resolved fragments.
+ Wiring wiring = rc.getWirings().get(fragCand.getResource());
+ if (wiring != null)
+ {
+ // Fragments only have host wire, so each wire represents
+ // an attached host.
+ for (Wire wire : wiring.getRequiredResourceWires(null))
+ {
+ // If the capability is a package, then make sure the
+ // host actually provides it in its resolved capabilities,
+ // since it may be a substitutable export.
+ if (!fragCand.getNamespace().equals(PackageNamespace.PACKAGE_NAMESPACE)
+ || rc.getWirings().get(wire.getProvider())
+ .getResourceCapabilities(null).contains(fragCand))
+ {
+ // Note that we can just add this as a candidate
+ // directly, since we know it is already resolved.
+ // NOTE: We are synthesizing a hosted capability here,
+ // but we are not using a ShadowList like we do when
+ // we synthesizing capabilities for unresolved hosts.
+ // It is not necessary to use the ShadowList here since
+ // the host is resolved, because in that case we can
+ // calculate the proper package space by traversing
+ // the wiring. In the unresolved case, this isn't possible
+ // so we need to use the ShadowList so we can keep
+ // a reference to a synthesized resource with attached
+ // fragments so we can correctly calculate its package
+ // space.
+ rc.insertHostedCapability(
+ candidates,
+ new WrappedCapability(
+ wire.getCapability().getResource(),
+ fragCand));
+ }
+ }
+ }
+ }
+ }
+
+ return rethrow;
+ }
+
+ public boolean isPopulated(Resource resource)
+ {
+ Object value = m_populateResultCache.get(resource);
+ return ((value != null) && (value instanceof Boolean));
+ }
+
+ public ResolutionException getResolveException(Resource resource)
+ {
+ Object value = m_populateResultCache.get(resource);
+ return ((value != null) && (value instanceof ResolutionException))
+ ? (ResolutionException) value : null;
+ }
+
+ /**
+ * Adds a requirement and its matching candidates to the internal data
+ * structure. This method assumes it owns the data being passed in and
+ * does not make a copy. It takes the data and processes, such as calculating
+ * which requirements depend on which capabilities and recording any fragments
+ * it finds for future merging.
+ * @param req the requirement to add.
+ * @param candidates the candidates matching the requirement.
+ **/
+ private void add(Requirement req, List<Capability> candidates)
+ {
+ if (req.getNamespace().equals(HostNamespace.HOST_NAMESPACE))
+ {
+ m_fragmentsPresent = true;
+ }
+
+ // Record the candidates.
+ m_candidateMap.put(req, candidates);
+ }
+
+ /**
+ * Adds requirements and candidates in bulk. The outer map is not retained
+ * by this method, but the inner data structures are, so they should not
+ * be further modified by the caller.
+ * @param candidates the bulk requirements and candidates to add.
+ **/
+ private void add(Map<Requirement, List<Capability>> candidates)
+ {
+ for (Entry<Requirement, List<Capability>> entry : candidates.entrySet())
+ {
+ add(entry.getKey(), entry.getValue());
+ }
+ }
+
+ /**
+ * Returns the wrapped module associated with the given module. If the module
+ * was not wrapped, then the module itself is returned. This is really only
+ * needed to determine if the root modules of the resolve have been wrapped.
+ * @param m the module whose wrapper is desired.
+ * @return the wrapper module or the module itself if it was not wrapped.
+ **/
+ public Resource getWrappedHost(Resource r)
+ {
+ Resource wrapped = m_allWrappedHosts.get(r);
+ return (wrapped == null) ? r : wrapped;
+ }
+
+ /**
+ * Gets the candidates associated with a given requirement.
+ * @param req the requirement whose candidates are desired.
+ * @return the matching candidates or null.
+ **/
+ public List<Capability> getCandidates(Requirement req)
+ {
+ return m_candidateMap.get(req);
+ }
+
+ /**
+ * Merges fragments into their hosts. It does this by wrapping all host
+ * modules and attaching their selected fragments, removing all unselected
+ * fragment modules, and replacing all occurrences of the original fragments
+ * in the internal data structures with the wrapped host modules instead.
+ * Thus, fragment capabilities and requirements are merged into the appropriate
+ * host and the candidates for the fragment now become candidates for the host.
+ * Likewise, any module depending on a fragment now depend on the host. Note
+ * that this process is sort of like multiplication, since one fragment that
+ * can attach to two hosts effectively gets multiplied across the two hosts.
+ * So, any modules being satisfied by the fragment will end up having the
+ * two hosts as potential candidates, rather than the single fragment.
+ * @param existingSingletons existing resolved singletons.
+ * @throws ResolveException if the removal of any unselected fragments result
+ * in the root module being unable to resolve.
+ **/
+ public void prepare(ResolveContext rc) throws ResolutionException
+ {
+ // Maps a host capability to a map containing its potential fragments;
+ // the fragment map maps a fragment symbolic name to a map that maps
+ // a version to a list of fragments requirements matching that symbolic
+ // name and version.
+ Map<Capability, Map<String, Map<Version, List<Requirement>>>>
+ hostFragments = Collections.EMPTY_MAP;
+ if (m_fragmentsPresent)
+ {
+ hostFragments = populateDependents();
+ }
+
+ // This method performs the following steps:
+ // 1. Select the fragments to attach to a given host.
+ // 2. Wrap hosts and attach fragments.
+ // 3. Remove any unselected fragments. This is necessary because
+ // other revisions may depend on the capabilities of unselected
+ // fragments, so we need to remove the unselected fragments and
+ // any revisions that depends on them, which could ultimately cause
+ // the entire resolve to fail.
+ // 4. Replace all fragments with any host it was merged into
+ // (effectively multiplying it).
+ // * This includes setting candidates for attached fragment
+ // requirements as well as replacing fragment capabilities
+ // with host's attached fragment capabilities.
+
+ // Steps 1 and 2
+ List<WrappedResource> hostResources = new ArrayList<WrappedResource>();
+ List<Resource> unselectedFragments = new ArrayList<Resource>();
+ for (Entry<Capability, Map<String, Map<Version, List<Requirement>>>>
+ hostEntry : hostFragments.entrySet())
+ {
+ // Step 1
+ Capability hostCap = hostEntry.getKey();
+ Map<String, Map<Version, List<Requirement>>> fragments
+ = hostEntry.getValue();
+ List<Resource> selectedFragments = new ArrayList<Resource>();
+ for (Entry<String, Map<Version, List<Requirement>>> fragEntry
+ : fragments.entrySet())
+ {
+ boolean isFirst = true;
+ for (Entry<Version, List<Requirement>> versionEntry
+ : fragEntry.getValue().entrySet())
+ {
+ for (Requirement hostReq : versionEntry.getValue())
+ {
+ // Selecting the first fragment in each entry, which
+ // is equivalent to selecting the highest version of
+ // each fragment with a given symbolic name.
+ if (isFirst)
+ {
+ selectedFragments.add(hostReq.getResource());
+ isFirst = false;
+ }
+ // For any fragment that wasn't selected, remove the
+ // current host as a potential host for it and remove it
+ // as a dependent on the host. If there are no more
+ // potential hosts for the fragment, then mark it as
+ // unselected for later removal.
+ else
+ {
+ m_dependentMap.get(hostCap).remove(hostReq);
+ List<Capability> hosts = m_candidateMap.get(hostReq);
+ hosts.remove(hostCap);
+ if (hosts.isEmpty())
+ {
+ unselectedFragments.add(hostReq.getResource());
+ }
+ }
+ }
+ }
+ }
+
+ // Step 2
+ WrappedResource wrappedHost =
+ new WrappedResource(hostCap.getResource(), selectedFragments);
+ hostResources.add(wrappedHost);
+ m_allWrappedHosts.put(hostCap.getResource(), wrappedHost);
+ }
+
+ // Step 3
+ for (Resource fragment : unselectedFragments)
+ {
+ removeResource(fragment,
+ new ResolutionException(
+ "Fragment was not selected for attachment: " + fragment));
+ }
+
+ // Step 4
+ for (WrappedResource hostResource : hostResources)
+ {
+ // Replaces capabilities from fragments with the capabilities
+ // from the merged host.
+ for (Capability c : hostResource.getCapabilities(null))
+ {
+ // Don't replace the host capability, since the fragment will
+ // really be attached to the original host, not the wrapper.
+ if (!c.getNamespace().equals(HostNamespace.HOST_NAMESPACE))
+ {
+ Capability origCap = ((HostedCapability) c).getDeclaredCapability();
+ // Note that you might think we could remove the original cap
+ // from the dependent map, but you can't since it may come from
+ // a fragment that is attached to multiple hosts, so each host
+ // will need to make their own copy.
+ Set<Requirement> dependents = m_dependentMap.get(origCap);
+ if (dependents != null)
+ {
+ dependents = new HashSet<Requirement>(dependents);
+ m_dependentMap.put(c, dependents);
+ for (Requirement r : dependents)
+ {
+ // We have synthesized hosted capabilities for all
+ // fragments that have been attached to hosts by
+ // wrapping the host bundle and their attached
+ // fragments. We need to use the ResolveContext to
+ // determine the proper priority order for hosted
+ // capabilities since the order may depend on the
+ // declaring host/fragment combination. However,
+ // internally we completely wrap the host revision
+ // and make all capabilities/requirements point back
+ // to the wrapped host not the declaring host. The
+ // ResolveContext expects HostedCapabilities to point
+ // to the declaring revision, so we need two separate
+ // candidate lists: one for the ResolveContext with
+ // HostedCapabilities pointing back to the declaring
+ // host and one for the resolver with HostedCapabilities
+ // pointing back to the wrapped host. We ask the
+ // ResolveContext to insert its appropriate HostedCapability
+ // into its list, then we mirror the insert into a
+ // shadow list with the resolver's HostedCapability.
+ // We only need to ask the ResolveContext to find
+ // the insert position for fragment caps since these
+ // were synthesized and we don't know their priority.
+ // However, in the resolver's candidate list we need
+ // to replace all caps with the wrapped caps, no
+ // matter if they come from the host or fragment,
+ // since we are completing replacing the declaring
+ // host and fragments with the wrapped host.
+ List<Capability> cands = m_candidateMap.get(r);
+ if (!(cands instanceof ShadowList))
+ {
+ ShadowList<Capability> shadow =
+ new ShadowList<Capability>(cands);
+ m_candidateMap.put(r, shadow);
+ cands = shadow;
+ }
+
+ // If the original capability is from a fragment, then
+ // ask the ResolveContext to insert it and update the
+ // shadow copy of the list accordingly.
+ if (!origCap.getResource().equals(hostResource.getDeclaredResource()))
+ {
+ List<Capability> original = ((ShadowList) cands).getOriginal();
+ int removeIdx = original.indexOf(origCap);
+ if (removeIdx != -1)
+ {
+ original.remove(removeIdx);
+ cands.remove(removeIdx);
+ }
+ int insertIdx = rc.insertHostedCapability(
+ original,
+ new SimpleHostedCapability(
+ hostResource.getDeclaredResource(),
+ origCap));
+ cands.add(insertIdx, c);
+ }
+ // If the original capability is from the host, then
+ // we just need to replace it in the shadow list.
+ else
+ {
+ int idx = cands.indexOf(origCap);
+ cands.set(idx, c);
+ }
+ }
+ }
+ }
+ }
+
+ // Copy candidates for fragment requirements to the host.
+ for (Requirement r : hostResource.getRequirements(null))
+ {
+ Requirement origReq = ((WrappedRequirement) r).getDeclaredRequirement();
+ List<Capability> cands = m_candidateMap.get(origReq);
+ if (cands != null)
+ {
+ m_candidateMap.put(r, new ArrayList<Capability>(cands));
+ for (Capability cand : cands)
+ {
+ Set<Requirement> dependents = m_dependentMap.get(cand);
+ dependents.remove(origReq);
+ dependents.add(r);
+ }
+ }
+ }
+ }
+
+ // Lastly, verify that all mandatory revisions are still
+ // populated, since some might have become unresolved after
+ // selecting fragments/singletons.
+ for (Resource resource : m_mandatoryResources)
+ {
+ if (!isPopulated(resource))
+ {
+ throw getResolveException(resource);
+ }
+ }
+ }
+
+ // Maps a host capability to a map containing its potential fragments;
+ // the fragment map maps a fragment symbolic name to a map that maps
+ // a version to a list of fragments requirements matching that symbolic
+ // name and version.
+ private Map<Capability,
+ Map<String, Map<Version, List<Requirement>>>> populateDependents()
+ {
+ Map<Capability, Map<String, Map<Version, List<Requirement>>>>
+ hostFragments = new HashMap<Capability,
+ Map<String, Map<Version, List<Requirement>>>>();
+ for (Entry<Requirement, List<Capability>> entry : m_candidateMap.entrySet())
+ {
+ Requirement req = entry.getKey();
+ List<Capability> caps = entry.getValue();
+ for (Capability cap : caps)
+ {
+ // Record the requirement as dependent on the capability.
+ Set<Requirement> dependents = m_dependentMap.get(cap);
+ if (dependents == null)
+ {
+ dependents = new HashSet<Requirement>();
+ m_dependentMap.put(cap, dependents);
+ }
+ dependents.add(req);
+
+ // Keep track of hosts and associated fragments.
+ if (req.getNamespace().equals(HostNamespace.HOST_NAMESPACE))
+ {
+ String resSymName = Util.getSymbolicName(req.getResource());
+ Version resVersion = Util.getVersion(req.getResource());
+
+ Map<String, Map<Version, List<Requirement>>>
+ fragments = hostFragments.get(cap);
+ if (fragments == null)
+ {
+ fragments = new HashMap<String, Map<Version, List<Requirement>>>();
+ hostFragments.put(cap, fragments);
+ }
+ Map<Version, List<Requirement>> fragmentVersions = fragments.get(resSymName);
+ if (fragmentVersions == null)
+ {
+ fragmentVersions =
+ new TreeMap<Version, List<Requirement>>(Collections.reverseOrder());
+ fragments.put(resSymName, fragmentVersions);
+ }
+ List<Requirement> actual = fragmentVersions.get(resVersion);
+ if (actual == null)
+ {
+ actual = new ArrayList<Requirement>();
+ fragmentVersions.put(resVersion, actual);
+ }
+ actual.add(req);
+ }
+ }
+ }
+
+ return hostFragments;
+ }
+
+ /**
+ * Removes a module from the internal data structures if it wasn't selected
+ * as a fragment or a singleton. This process may cause other modules to
+ * become unresolved if they depended on the module's capabilities and there
+ * is no other candidate.
+ * @param revision the module to remove.
+ * @throws ResolveException if removing the module caused the resolve to fail.
+ **/
+ private void removeResource(Resource resource, ResolutionException ex)
+ throws ResolutionException
+ {
+ // Add removal reason to result cache.
+ m_populateResultCache.put(resource, ex);
+ // Remove from dependents.
+ Set<Resource> unresolvedResources = new HashSet<Resource>();
+ remove(resource, unresolvedResources);
+ // Remove dependents that failed as a result of removing revision.
+ while (!unresolvedResources.isEmpty())
+ {
+ Iterator<Resource> it = unresolvedResources.iterator();
+ resource = it.next();
+ it.remove();
+ remove(resource, unresolvedResources);
+ }
+ }
+
+ /**
+ * Removes the specified module from the internal data structures, which
+ * involves removing its requirements and its capabilities. This may cause
+ * other modules to become unresolved as a result.
+ * @param br the module to remove.
+ * @param unresolvedRevisions a list to containing any additional modules that
+ * that became unresolved as a result of removing this module and will
+ * also need to be removed.
+ * @throws ResolveException if removing the module caused the resolve to fail.
+ **/
+ private void remove(Resource resource, Set<Resource> unresolvedResources)
+ throws ResolutionException
+ {
+ for (Requirement r : resource.getRequirements(null))
+ {
+ remove(r);
+ }
+
+ for (Capability c : resource.getCapabilities(null))
+ {
+ remove(c, unresolvedResources);
+ }
+ }
+
+ /**
+ * Removes a requirement from the internal data structures.
+ * @param req the requirement to remove.
+ **/
+ private void remove(Requirement req)
+ {
+ boolean isFragment = req.getNamespace().equals(HostNamespace.HOST_NAMESPACE);
+
+ List<Capability> candidates = m_candidateMap.remove(req);
+ if (candidates != null)
+ {
+ for (Capability cap : candidates)
+ {
+ Set<Requirement> dependents = m_dependentMap.get(cap);
+ if (dependents != null)
+ {
+ dependents.remove(req);
+ }
+ }
+ }
+ }
+
+ /**
+ * Removes a capability from the internal data structures. This may cause
+ * other modules to become unresolved as a result.
+ * @param c the capability to remove.
+ * @param unresolvedRevisions a list to containing any additional modules that
+ * that became unresolved as a result of removing this module and will
+ * also need to be removed.
+ * @throws ResolveException if removing the module caused the resolve to fail.
+ **/
+ private void remove(Capability c, Set<Resource> unresolvedResources)
+ throws ResolutionException
+ {
+ Set<Requirement> dependents = m_dependentMap.remove(c);
+ if (dependents != null)
+ {
+ for (Requirement r : dependents)
+ {
+ List<Capability> candidates = m_candidateMap.get(r);
+ candidates.remove(c);
+ if (candidates.isEmpty())
+ {
+ m_candidateMap.remove(r);
+ if (!Util.isOptional(r))
+ {
+ String msg = "Unable to resolve " + r.getResource()
+ + ": missing requirement " + r;
+ m_populateResultCache.put(
+ r.getResource(),
+ new ResolutionException(msg, null, Collections.singleton(r)));
+ unresolvedResources.add(r.getResource());
+ }
+ }
+ }
+ }
+ }
+
+ /**
+ * Creates a copy of the Candidates object. This is used for creating
+ * permutations when package space conflicts are discovered.
+ * @return copy of this Candidates object.
+ **/
+ public Candidates copy()
+ {
+ Map<Capability, Set<Requirement>> dependentMap =
+ new HashMap<Capability, Set<Requirement>>();
+ for (Entry<Capability, Set<Requirement>> entry : m_dependentMap.entrySet())
+ {
+ Set<Requirement> dependents = new HashSet<Requirement>(entry.getValue());
+ dependentMap.put(entry.getKey(), dependents);
+ }
+
+ Map<Requirement, List<Capability>> candidateMap =
+ new HashMap<Requirement, List<Capability>>();
+ for (Entry<Requirement, List<Capability>> entry
+ : m_candidateMap.entrySet())
+ {
+ List<Capability> candidates =
+ new ArrayList<Capability>(entry.getValue());
+ candidateMap.put(entry.getKey(), candidates);
+ }
+
+ return new Candidates(
+ m_mandatoryResources, dependentMap, candidateMap,
+ m_allWrappedHosts, m_populateResultCache, m_fragmentsPresent);
+ }
+
+ public void dump(ResolveContext rc)
+ {
+ // Create set of all revisions from requirements.
+ Set<Resource> resources = new HashSet<Resource>();
+ for (Entry<Requirement, List<Capability>> entry
+ : m_candidateMap.entrySet())
+ {
+ resources.add(entry.getKey().getResource());
+ }
+ // Now dump the revisions.
+ System.out.println("=== BEGIN CANDIDATE MAP ===");
+ for (Resource resource : resources)
+ {
+ Wiring wiring = rc.getWirings().get(resource);
+ System.out.println(" " + resource
+ + " (" + ((wiring != null) ? "RESOLVED)" : "UNRESOLVED)"));
+ List<Requirement> reqs = (wiring != null)
+ ? wiring.getResourceRequirements(null)
+ : resource.getRequirements(null);
+ for (Requirement req : reqs)
+ {
+ List<Capability> candidates = m_candidateMap.get(req);
+ if ((candidates != null) && (candidates.size() > 0))
+ {
+ System.out.println(" " + req + ": " + candidates);
+ }
+ }
+ reqs = (wiring != null)
+ ? Util.getDynamicRequirements(wiring.getResourceRequirements(null))
+ : Util.getDynamicRequirements(resource.getRequirements(null));
+ for (Requirement req : reqs)
+ {
+ List<Capability> candidates = m_candidateMap.get(req);
+ if ((candidates != null) && (candidates.size() > 0))
+ {
+ System.out.println(" " + req + ": " + candidates);
+ }
+ }
+ }
+ System.out.println("=== END CANDIDATE MAP ===");
+ }
+}
\ No newline at end of file