| /* |
| * 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.util; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.osgi.resource.Capability; |
| |
| public class CandidateSelector { |
| protected final AtomicBoolean isUnmodifiable; |
| protected final List<Capability> unmodifiable; |
| private int currentIndex = 0; |
| |
| public CandidateSelector(List<Capability> candidates, AtomicBoolean isUnmodifiable) { |
| this.isUnmodifiable = isUnmodifiable; |
| this.unmodifiable = new ArrayList<Capability>(candidates); |
| } |
| |
| protected CandidateSelector(CandidateSelector candidateSelector) { |
| this.isUnmodifiable = candidateSelector.isUnmodifiable; |
| this.unmodifiable = candidateSelector.unmodifiable; |
| this.currentIndex = candidateSelector.currentIndex; |
| } |
| |
| public CandidateSelector copy() { |
| return new CandidateSelector(this); |
| } |
| |
| public int getRemainingCandidateCount() { |
| return unmodifiable.size() - currentIndex; |
| } |
| |
| public Capability getCurrentCandidate() { |
| return currentIndex < unmodifiable.size() ? unmodifiable.get(currentIndex) : null; |
| } |
| |
| public List<Capability> getRemainingCandidates() { |
| return Collections.unmodifiableList(unmodifiable.subList(currentIndex, unmodifiable.size())); |
| } |
| |
| public boolean isEmpty() { |
| return unmodifiable.size() <= currentIndex; |
| } |
| |
| public Capability removeCurrentCandidate() { |
| Capability current = getCurrentCandidate(); |
| if (current != null) { |
| currentIndex += 1; |
| } |
| return current; |
| } |
| |
| public String toString() { |
| return getRemainingCandidates().toString(); |
| } |
| |
| public int remove(Capability cap) { |
| checkModifiable(); |
| int index = unmodifiable.indexOf(cap); |
| if (index != -1) { |
| unmodifiable.remove(index); |
| } |
| return index; |
| } |
| |
| protected void checkModifiable() { |
| if (isUnmodifiable.get()) { |
| throw new IllegalStateException("Trying to mutate after candidates have been prepared."); |
| } |
| } |
| } |