1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
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23 package gc.g1.unloading.check;
24 
25 import java.util.*;
26 
27 /**
28  * This is the storage for assertions. Here assertions are stored until required number of garbage collections happen.
29  * This container isn't thread-safe.
30  */
31 public class AssertionContainer {
32 
33     private SortedMap<Long, List<Assertion>> sortedMap = new TreeMap<>();
34 
35     /**
36      * Enqueue assertion to storage.
37      * @param assertions
38      * @param gcCounter - gc counter value as of assertion created
39      */
enqueue(Collection<Assertion> assertions, Long gcCounter)40     public void enqueue(Collection<Assertion> assertions, Long gcCounter) {
41         if (sortedMap.get(gcCounter) != null) {
42             sortedMap.get(gcCounter).addAll(assertions);
43         } else {
44             List<Assertion> newList = new LinkedList<>();
45             newList.addAll(assertions);
46             sortedMap.put(gcCounter, newList);
47         }
48     }
49 
50     /**
51      * Get assertions that are ready for check. That means they where created when gc counter was less then
52      * specified value.
53      * @param bound - value of gc counter
54      * @return - collection of assertions. It can be empty if no assertions are mature yet.
55      */
getElder(Long bound)56     public Collection<Assertion> getElder(Long bound) {
57         Collection<Assertion> returnValue = new LinkedList<>();
58         SortedMap<Long, List<Assertion>> filteredView = sortedMap.headMap(bound);
59         for (Long l : filteredView.keySet()) {
60             List<Assertion> list = filteredView.remove(l);
61             returnValue.addAll(list);
62         }
63         return returnValue;
64     }
65 
66 }
67