8023339: Refined Collection.removeIf UOE conditions

Reviewed-by: mduigou
Contributed-by: paul.sandoz@oracle.com

src/share/classes/java/util/Collection.java

@@ -379,8 +379,8 @@ public interface Collection<E> extends Iterable<E> {
 
     /**
      * Removes all of the elements of this collection that satisfy the given
-     * predicate.  Errors or runtime exceptions thrown by the predicate are
-     * relayed to the caller.
+     * predicate.  Errors or runtime exceptions thrown during iteration or by
+     * the predicate are relayed to the caller.
      *
      * @implSpec
      * The default implementation traverses all elements of the collection using
@@ -393,9 +393,10 @@ public interface Collection<E> extends Iterable<E> {
      *        removed
      * @return {@code true} if any elements were removed
      * @throws NullPointerException if the specified filter is null
-     * @throws UnsupportedOperationException if the {@code remove}
-     *         method is not supported by this collection's
-     *         {@link #iterator}
+     * @throws UnsupportedOperationException if elements cannot be removed
+     *         from this collection.  Implementations may throw this exception if a
+     *         matching element cannot be removed or if, in general, removal is not
+     *         supported.
      * @since 1.8
      */
     default boolean removeIf(Predicate<? super E> filter) {

test/java/util/Collection/MOAT.java

@@ -207,8 +207,8 @@ public class MOAT {
                new Fun(){void f(){ it.next(); }});
 
         try { it.remove(); }
-        catch (IllegalStateException _) { pass(); }
-        catch (UnsupportedOperationException _) { pass(); }
+        catch (IllegalStateException ignored) { pass(); }
+        catch (UnsupportedOperationException ignored) { pass(); }
         catch (Throwable t) { unexpected(t); }
 
         if (rnd.nextBoolean())
@@ -280,9 +280,9 @@ public class MOAT {
         testEmptyCollection(m.values());
 
         try { check(! m.containsValue(null)); }
-        catch (NullPointerException _) { /* OK */ }
+        catch (NullPointerException ignored) { /* OK */ }
         try { check(! m.containsKey(null)); }
-        catch (NullPointerException _) { /* OK */ }
+        catch (NullPointerException ignored) { /* OK */ }
         check(! m.containsValue(1));
         check(! m.containsKey(1));
     }
@@ -710,8 +710,8 @@ public class MOAT {
             l.addAll(-1, Collections.<Integer>emptyList());
             fail("Expected IndexOutOfBoundsException not thrown");
         }
-        catch (UnsupportedOperationException _) {/* OK */}
-        catch (IndexOutOfBoundsException _) {/* OK */}
+        catch (UnsupportedOperationException ignored) {/* OK */}
+        catch (IndexOutOfBoundsException ignored) {/* OK */}
         catch (Throwable t) { unexpected(t); }
 
 //      equal(l instanceof Serializable,