Internal change.

RELNOTES=n/a PiperOrigin-RevId: 646915665
google · Jun 26, 2024 · 4b96e43 · 4b96e43
1 parent b50df33
commit 4b96e43
Show file tree

Hide file tree

Showing 4 changed files with 48 additions and 40 deletions.
diff --git a/android/guava-tests/test/com/google/common/util/concurrent/StripedTest.java b/android/guava-tests/test/com/google/common/util/concurrent/StripedTest.java
@@ -50,22 +50,8 @@ private static List<Striped<?>> strongImplementations() {
         Striped.readWriteLock(256),
         Striped.lock(100),
         Striped.lock(256),
-        Striped.custom(
-            100,
-            new Supplier<Lock>() {
-              @Override
-              public Lock get() {
-                return new ReentrantLock(true);
-              }
-            }),
-        Striped.custom(
-            256,
-            new Supplier<Lock>() {
-              @Override
-              public Lock get() {
-                return new ReentrantLock(true);
-              }
-            }),
+        Striped.custom(100, FAIR_LOCK_SUPPLER),
+        Striped.custom(256, FAIR_LOCK_SUPPLER),
         Striped.semaphore(100, 1),
         Striped.semaphore(256, 1));
   }
@@ -86,6 +72,14 @@ public Lock get() {
         }
       };
 
+  private static final Supplier<Lock> FAIR_LOCK_SUPPLER =
+      new Supplier<Lock>() {
+        @Override
+        public Lock get() {
+          return new ReentrantLock(true);
+        }
+      };
+
   private static final Supplier<Semaphore> SEMAPHORE_SUPPLER =
       new Supplier<Semaphore>() {
         @Override
@@ -108,6 +102,8 @@ private static List<Striped<?>> weakImplementations() {
         .add(new Striped.SmallLazyStriped<Semaphore>(64, SEMAPHORE_SUPPLER))
         .add(new Striped.LargeLazyStriped<Semaphore>(50, SEMAPHORE_SUPPLER))
         .add(new Striped.LargeLazyStriped<Semaphore>(64, SEMAPHORE_SUPPLER))
+        .add(Striped.lazyWeakCustom(50, FAIR_LOCK_SUPPLER))
+        .add(Striped.lazyWeakCustom(64, FAIR_LOCK_SUPPLER))
         .build();
   }
 

diff --git a/android/guava/src/com/google/common/util/concurrent/Striped.java b/android/guava/src/com/google/common/util/concurrent/Striped.java
@@ -217,10 +217,18 @@ public static Striped<Lock> lock(int stripes) {
    * @return a new {@code Striped<Lock>}
    */
   public static Striped<Lock> lazyWeakLock(int stripes) {
-    return lazy(stripes, () -> new ReentrantLock(false));
+    return lazyWeakCustom(stripes, () -> new ReentrantLock(false));
   }
 
-  private static <L> Striped<L> lazy(int stripes, Supplier<L> supplier) {
+  /**
+   * Creates a {@code Striped<L>} with lazily initialized, weakly referenced locks. Every lock is
+   * obtained from the passed supplier.
+   *
+   * @param stripes the minimum number of stripes (locks) required
+   * @param supplier a {@code Supplier<L>} object to obtain locks from
+   * @return a new {@code Striped<L>}
+   */
+  static <L> Striped<L> lazyWeakCustom(int stripes, Supplier<L> supplier) {
     return stripes < LARGE_LAZY_CUTOFF
         ? new SmallLazyStriped<L>(stripes, supplier)
         : new LargeLazyStriped<L>(stripes, supplier);
@@ -247,7 +255,7 @@ public static Striped<Semaphore> semaphore(int stripes, int permits) {
    * @return a new {@code Striped<Semaphore>}
    */
   public static Striped<Semaphore> lazyWeakSemaphore(int stripes, int permits) {
-    return lazy(stripes, () -> new Semaphore(permits, false));
+    return lazyWeakCustom(stripes, () -> new Semaphore(permits, false));
   }
 
   /**
@@ -269,7 +277,7 @@ public static Striped<ReadWriteLock> readWriteLock(int stripes) {
    * @return a new {@code Striped<ReadWriteLock>}
    */
   public static Striped<ReadWriteLock> lazyWeakReadWriteLock(int stripes) {
-    return lazy(stripes, WeakSafeReadWriteLock::new);
+    return lazyWeakCustom(stripes, WeakSafeReadWriteLock::new);
   }
   /**
    * ReadWriteLock implementation whose read and write locks retain a reference back to this lock.

diff --git a/guava-tests/test/com/google/common/util/concurrent/StripedTest.java b/guava-tests/test/com/google/common/util/concurrent/StripedTest.java
@@ -50,22 +50,8 @@ private static List<Striped<?>> strongImplementations() {
         Striped.readWriteLock(256),
         Striped.lock(100),
         Striped.lock(256),
-        Striped.custom(
-            100,
-            new Supplier<Lock>() {
-              @Override
-              public Lock get() {
-                return new ReentrantLock(true);
-              }
-            }),
-        Striped.custom(
-            256,
-            new Supplier<Lock>() {
-              @Override
-              public Lock get() {
-                return new ReentrantLock(true);
-              }
-            }),
+        Striped.custom(100, FAIR_LOCK_SUPPLER),
+        Striped.custom(256, FAIR_LOCK_SUPPLER),
         Striped.semaphore(100, 1),
         Striped.semaphore(256, 1));
   }
@@ -86,6 +72,14 @@ public Lock get() {
         }
       };
 
+  private static final Supplier<Lock> FAIR_LOCK_SUPPLER =
+      new Supplier<Lock>() {
+        @Override
+        public Lock get() {
+          return new ReentrantLock(true);
+        }
+      };
+
   private static final Supplier<Semaphore> SEMAPHORE_SUPPLER =
       new Supplier<Semaphore>() {
         @Override
@@ -108,6 +102,8 @@ private static List<Striped<?>> weakImplementations() {
         .add(new Striped.SmallLazyStriped<Semaphore>(64, SEMAPHORE_SUPPLER))
         .add(new Striped.LargeLazyStriped<Semaphore>(50, SEMAPHORE_SUPPLER))
         .add(new Striped.LargeLazyStriped<Semaphore>(64, SEMAPHORE_SUPPLER))
+        .add(Striped.lazyWeakCustom(50, FAIR_LOCK_SUPPLER))
+        .add(Striped.lazyWeakCustom(64, FAIR_LOCK_SUPPLER))
         .build();
   }
 

diff --git a/guava/src/com/google/common/util/concurrent/Striped.java b/guava/src/com/google/common/util/concurrent/Striped.java
@@ -217,10 +217,18 @@ public static Striped<Lock> lock(int stripes) {
    * @return a new {@code Striped<Lock>}
    */
   public static Striped<Lock> lazyWeakLock(int stripes) {
-    return lazy(stripes, () -> new ReentrantLock(false));
+    return lazyWeakCustom(stripes, () -> new ReentrantLock(false));
   }
 
-  private static <L> Striped<L> lazy(int stripes, Supplier<L> supplier) {
+  /**
+   * Creates a {@code Striped<L>} with lazily initialized, weakly referenced locks. Every lock is
+   * obtained from the passed supplier.
+   *
+   * @param stripes the minimum number of stripes (locks) required
+   * @param supplier a {@code Supplier<L>} object to obtain locks from
+   * @return a new {@code Striped<L>}
+   */
+  static <L> Striped<L> lazyWeakCustom(int stripes, Supplier<L> supplier) {
     return stripes < LARGE_LAZY_CUTOFF
         ? new SmallLazyStriped<L>(stripes, supplier)
         : new LargeLazyStriped<L>(stripes, supplier);
@@ -247,7 +255,7 @@ public static Striped<Semaphore> semaphore(int stripes, int permits) {
    * @return a new {@code Striped<Semaphore>}
    */
   public static Striped<Semaphore> lazyWeakSemaphore(int stripes, int permits) {
-    return lazy(stripes, () -> new Semaphore(permits, false));
+    return lazyWeakCustom(stripes, () -> new Semaphore(permits, false));
   }
 
   /**
@@ -269,7 +277,7 @@ public static Striped<ReadWriteLock> readWriteLock(int stripes) {
    * @return a new {@code Striped<ReadWriteLock>}
    */
   public static Striped<ReadWriteLock> lazyWeakReadWriteLock(int stripes) {
-    return lazy(stripes, WeakSafeReadWriteLock::new);
+    return lazyWeakCustom(stripes, WeakSafeReadWriteLock::new);
   }
   /**
    * ReadWriteLock implementation whose read and write locks retain a reference back to this lock.