[Bug classpath/80688] New: gnu.java.util.LRUCache is not LRU

[guillerodriguez.dev at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80688

            Bug ID: 80688
           Summary: gnu.java.util.LRUCache is not LRU
           Product: classpath
           Version: 0.99
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: classpath
          Assignee: unassigned at gcc dot gnu.org
          Reporter: guillerodriguez.dev at gmail dot com
  Target Milestone: ---

According to the documentation, class gnu.java.util.LRUCache is "A least
recently used cache, based on LinkedHashMap".

However the only constructor of the class calls the no-arg constructor of the
superclass, LinkedHashMap, which by default creates an insertion-ordered
(instead of access-ordered) LinkedHashMap.

Thus when the LRUCache is full it will not discard the least recently used
items. Instead it will discard the first items that were inserted.

In order to behave as a LRU cache, an access-ordered LinkedHashMap must be
created:

  public LRUCache(int cap)
  {
-   super();
+   super(11, 0.75f, true);
    capacity = cap;
  }