-
Notifications
You must be signed in to change notification settings - Fork 2.3k
/
AllByPrioritySelectionStrategy.java
60 lines (54 loc) · 2.25 KB
/
AllByPrioritySelectionStrategy.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
/*
* Copyright (c) 2002-2017 "Neo Technology,"
* Network Engine for Objects in Lund AB [http://neotechnology.com]
*
* This file is part of Neo4j.
*
* Neo4j is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.neo4j.kernel.extension.dependency;
import java.util.Collections;
import java.util.List;
import org.neo4j.graphdb.DependencyResolver;
import org.neo4j.helpers.collection.Iterables;
import static org.neo4j.kernel.extension.KernelExtensionUtil.servicesClassPathEntryInformation;
/**
* Selects the candidate with highest priority (assumed to implement {@link Comparable}) and returns
* in {@link #select(Class, Iterable)}, but keeps the others for access too.
*/
public class AllByPrioritySelectionStrategy<T> implements DependencyResolver.SelectionStrategy
{
@SuppressWarnings( "rawtypes" )
private List lowerPrioritizedCandidates = Collections.emptyList();
@SuppressWarnings( {"rawtypes", "unchecked"} )
@Override
public <R> R select( Class<R> type, Iterable<R> candidates ) throws IllegalArgumentException
{
List<Comparable> all = (List<Comparable>) Iterables.asList( candidates );
if ( all.isEmpty() )
{
throw new IllegalArgumentException( "Could not resolve dependency of type: " +
type.getName() + ". " + servicesClassPathEntryInformation() );
}
Collections.sort( all, Collections.reverseOrder() );
R highest = (R) all.remove( 0 );
lowerPrioritizedCandidates = all;
return highest;
}
@SuppressWarnings( "unchecked" )
public Iterable<T> lowerPrioritizedCandidates()
{
return lowerPrioritizedCandidates;
}
}