| // |
| // ======================================================================== |
| // Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd. |
| // ------------------------------------------------------------------------ |
| // All rights reserved. This program and the accompanying materials |
| // are made available under the terms of the Eclipse Public License v1.0 |
| // and Apache License v2.0 which accompanies this distribution. |
| // |
| // The Eclipse Public License is available at |
| // http://www.eclipse.org/legal/epl-v10.html |
| // |
| // The Apache License v2.0 is available at |
| // http://www.opensource.org/licenses/apache2.0.php |
| // |
| // You may elect to redistribute this code under either of these licenses. |
| // ======================================================================== |
| // |
| |
| package org.eclipse.jetty.webapp; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Set; |
| import java.util.function.Consumer; |
| |
| import org.eclipse.jetty.util.TopologicalSort; |
| import org.eclipse.jetty.util.resource.Resource; |
| |
| /** |
| * Relative Fragment Ordering |
| * <p>Uses a {@link TopologicalSort} to order the fragments.</p> |
| */ |
| public class RelativeOrdering implements Ordering |
| { |
| protected MetaData _metaData; |
| |
| public RelativeOrdering (MetaData metaData) |
| { |
| _metaData = metaData; |
| } |
| |
| @Override |
| public List<Resource> order(List<Resource> jars) |
| { |
| TopologicalSort<Resource> sort = new TopologicalSort<>(); |
| List<Resource> sorted = new ArrayList<>(jars); |
| Set<Resource> others = new HashSet<>(); |
| Set<Resource> before_others = new HashSet<>(); |
| Set<Resource> after_others = new HashSet<>(); |
| |
| // Pass 1: split the jars into 'before others', 'others' or 'after others' |
| for (Resource jar : jars) |
| { |
| FragmentDescriptor fragment=_metaData.getFragment(jar); |
| |
| if (fragment == null) |
| others.add(jar); |
| else |
| { |
| switch (fragment.getOtherType()) |
| { |
| case None: |
| others.add(jar); |
| break; |
| case Before: |
| before_others.add(jar); |
| break; |
| case After: |
| after_others.add(jar); |
| break; |
| } |
| } |
| } |
| |
| // Pass 2: Add sort dependencies for each jar |
| Set<Resource> referenced = new HashSet<>(); |
| for (Resource jar : jars) |
| { |
| FragmentDescriptor fragment=_metaData.getFragment(jar); |
| |
| if (fragment != null) |
| { |
| // Add each explicit 'after' ordering as a sort dependency |
| // and remember that the dependency has been referenced. |
| for (String name: fragment.getAfters()) |
| { |
| Resource after=_metaData.getJarForFragment(name); |
| sort.addDependency(jar,after); |
| referenced.add(after); |
| } |
| |
| // Add each explicit 'before' ordering as a sort dependency |
| // and remember that the dependency has been referenced. |
| for (String name: fragment.getBefores()) |
| { |
| Resource before=_metaData.getJarForFragment(name); |
| sort.addDependency(before,jar); |
| referenced.add(before); |
| } |
| |
| // handle the others |
| switch (fragment.getOtherType()) |
| { |
| case None: |
| break; |
| case Before: |
| // Add a dependency on this jar from all |
| // jars in the 'others' and 'after others' sets, but |
| // exclude any jars we have already explicitly |
| // referenced above. |
| Consumer<Resource> add_before = other -> |
| { |
| if (!referenced.contains(other)) |
| sort.addDependency(other,jar); |
| }; |
| others.forEach(add_before); |
| after_others.forEach(add_before); |
| break; |
| |
| case After: |
| // Add a dependency from this jar to all |
| // jars in the 'before others' and 'others' sets, but |
| // exclude any jars we have already explicitly |
| // referenced above. |
| Consumer<Resource> add_after = other -> |
| { |
| if (!referenced.contains(other)) |
| sort.addDependency(jar,other); |
| }; |
| before_others.forEach(add_after); |
| others.forEach(add_after); |
| break; |
| } |
| } |
| referenced.clear(); |
| } |
| |
| // sort the jars according to the added dependencies |
| sort.sort(sorted); |
| |
| return sorted; |
| } |
| } |