Avoid exposing some types outside the scope in which those types are …

…visible.

Java doesn't mind this, but it's not like it's accomplishing anything for us.

I've tried to make things `private` where possible and fallen back to making types package-private where necessary.

(In `Synchronized`, I made everything package-private for consistency, rather than trying to trace through the class hierarchies to expose only the types that need it.)

I also sprinkled in some `final` keywords while I was in the area.

RELNOTES=n/a
PiperOrigin-RevId: 573211489

android/guava/src/com/google/common/base/MoreObjects.java

@@ -428,7 +428,7 @@ private ToStringHelper addUnconditionalHolder(String name, Object value) {
     }
 
     // Holder object for values that might be null and/or empty.
-    private static class ValueHolder {
+    static class ValueHolder {
       @CheckForNull String name;
       @CheckForNull Object value;
       @CheckForNull ValueHolder next;

android/guava/src/com/google/common/collect/AbstractMapBasedMultimap.java

@@ -1050,7 +1050,7 @@ public SortedSet<K> tailSet(@ParametricNullness K fromElement) {
   }
 
   @WeakOuter
-  class NavigableKeySet extends SortedKeySet implements NavigableSet<K> {
+  private final class NavigableKeySet extends SortedKeySet implements NavigableSet<K> {
     NavigableKeySet(NavigableMap<K, Collection<V>> subMap) {
       super(subMap);
     }
@@ -1507,7 +1507,7 @@ SortedSet<K> createKeySet() {
     }
   }
 
-  class NavigableAsMap extends SortedAsMap implements NavigableMap<K, Collection<V>> {
+  private final class NavigableAsMap extends SortedAsMap implements NavigableMap<K, Collection<V>> {
 
     NavigableAsMap(NavigableMap<K, Collection<V>> submap) {
       super(submap);

android/guava/src/com/google/common/collect/LinkedHashMultimap.java

@@ -189,11 +189,11 @@ static final class ValueEntry<K extends @Nullable Object, V extends @Nullable Ob
      * frameworks like Android that define post-construct hooks like Activity.onCreate, etc.
      */
 
-    @CheckForNull ValueSetLink<K, V> predecessorInValueSet;
-    @CheckForNull ValueSetLink<K, V> successorInValueSet;
+    @CheckForNull private ValueSetLink<K, V> predecessorInValueSet;
+    @CheckForNull private ValueSetLink<K, V> successorInValueSet;
 
-    @CheckForNull ValueEntry<K, V> predecessorInMultimap;
-    @CheckForNull ValueEntry<K, V> successorInMultimap;
+    @CheckForNull private ValueEntry<K, V> predecessorInMultimap;
+    @CheckForNull private ValueEntry<K, V> successorInMultimap;
 
     ValueEntry(
         @ParametricNullness K key,

android/guava/src/com/google/common/collect/LinkedListMultimap.java

@@ -105,7 +105,7 @@ public class LinkedListMultimap<K extends @Nullable Object, V extends @Nullable
    * ValueForKeyIterator} in constant time.
    */
 
-  private static final class Node<K extends @Nullable Object, V extends @Nullable Object>
+  static final class Node<K extends @Nullable Object, V extends @Nullable Object>
       extends AbstractMapEntry<K, V> {
     @ParametricNullness final K key;
     @ParametricNullness V value;

android/guava/src/com/google/common/collect/MinMaxPriorityQueue.java

@@ -521,7 +521,7 @@ boolean isIntact() {
    * sake they are stored interleaved on alternate heap levels in the same array (MMPQ.queue).
    */
   @WeakOuter
-  private class Heap {
+  class Heap {
     final Ordering<E> ordering;
 
     @SuppressWarnings("nullness:initialization.field.uninitialized")

android/guava/src/com/google/common/collect/StandardTable.java

@@ -821,7 +821,7 @@ protected Set<Entry<R, Map<C, V>>> createEntrySet() {
     }
 
     @WeakOuter
-    class EntrySet extends TableSet<Entry<R, Map<C, V>>> {
+    private final class EntrySet extends TableSet<Entry<R, Map<C, V>>> {
       @Override
       public Iterator<Entry<R, Map<C, V>>> iterator() {
         return Maps.asMapEntryIterator(
@@ -910,7 +910,7 @@ Collection<Map<R, V>> createValues() {
     }
 
     @WeakOuter
-    class ColumnMapEntrySet extends TableSet<Entry<C, Map<R, V>>> {
+    private final class ColumnMapEntrySet extends TableSet<Entry<C, Map<R, V>>> {
       @Override
       public Iterator<Entry<C, Map<R, V>>> iterator() {
         return Maps.asMapEntryIterator(

android/guava/src/com/google/common/collect/Synchronized.java

@@ -326,8 +326,8 @@ public E last() {
         : new SynchronizedList<E>(list, mutex);
   }
 
-  private static class SynchronizedList<E extends @Nullable Object>
-      extends SynchronizedCollection<E> implements List<E> {
+  static class SynchronizedList<E extends @Nullable Object> extends SynchronizedCollection<E>
+      implements List<E> {
     SynchronizedList(List<E> delegate, @CheckForNull Object mutex) {
       super(delegate, mutex);
     }
@@ -423,7 +423,7 @@ public int hashCode() {
     private static final long serialVersionUID = 0;
   }
 
-  private static class SynchronizedRandomAccessList<E extends @Nullable Object>
+  static final class SynchronizedRandomAccessList<E extends @Nullable Object>
       extends SynchronizedList<E> implements RandomAccess {
     SynchronizedRandomAccessList(List<E> list, @CheckForNull Object mutex) {
       super(list, mutex);
@@ -440,7 +440,7 @@ private static class SynchronizedRandomAccessList<E extends @Nullable Object>
     return new SynchronizedMultiset<E>(multiset, mutex);
   }
 
-  private static class SynchronizedMultiset<E extends @Nullable Object>
+  static final class SynchronizedMultiset<E extends @Nullable Object>
       extends SynchronizedCollection<E> implements Multiset<E> {
     @CheckForNull transient Set<E> elementSet;
     @CheckForNull transient Set<Multiset.Entry<E>> entrySet;
@@ -537,7 +537,7 @@ public int hashCode() {
     return new SynchronizedMultimap<>(multimap, mutex);
   }
 
-  private static class SynchronizedMultimap<K extends @Nullable Object, V extends @Nullable Object>
+  static class SynchronizedMultimap<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedObject implements Multimap<K, V> {
     @CheckForNull transient Set<K> keySet;
     @CheckForNull transient Collection<V> valuesCollection;
@@ -724,7 +724,7 @@ public int hashCode() {
     return new SynchronizedListMultimap<>(multimap, mutex);
   }
 
-  private static class SynchronizedListMultimap<
+  static final class SynchronizedListMultimap<
           K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedMultimap<K, V> implements ListMultimap<K, V> {
     SynchronizedListMultimap(ListMultimap<K, V> delegate, @CheckForNull Object mutex) {
@@ -768,8 +768,7 @@ public List<V> replaceValues(K key, Iterable<? extends V> values) {
     return new SynchronizedSetMultimap<>(multimap, mutex);
   }
 
-  private static class SynchronizedSetMultimap<
-          K extends @Nullable Object, V extends @Nullable Object>
+  static class SynchronizedSetMultimap<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedMultimap<K, V> implements SetMultimap<K, V> {
     @CheckForNull transient Set<Map.Entry<K, V>> entrySet;
 
@@ -825,7 +824,7 @@ SortedSetMultimap<K, V> sortedSetMultimap(
     return new SynchronizedSortedSetMultimap<>(multimap, mutex);
   }
 
-  private static class SynchronizedSortedSetMultimap<
+  static final class SynchronizedSortedSetMultimap<
           K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedSetMultimap<K, V> implements SortedSetMultimap<K, V> {
     SynchronizedSortedSetMultimap(SortedSetMultimap<K, V> delegate, @CheckForNull Object mutex) {
@@ -892,7 +891,7 @@ public Comparator<? super V> valueComparator() {
     }
   }
 
-  private static class SynchronizedAsMapEntries<
+  static final class SynchronizedAsMapEntries<
           K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedSet<Map.Entry<K, Collection<V>>> {
     SynchronizedAsMapEntries(
@@ -999,7 +998,7 @@ public boolean retainAll(Collection<?> c) {
     return new SynchronizedMap<>(map, mutex);
   }
 
-  private static class SynchronizedMap<K extends @Nullable Object, V extends @Nullable Object>
+  static class SynchronizedMap<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedObject implements Map<K, V> {
     @CheckForNull transient Set<K> keySet;
     @CheckForNull transient Collection<V> values;
@@ -1202,8 +1201,7 @@ public SortedMap<K, V> tailMap(K fromKey) {
     return new SynchronizedBiMap<>(bimap, mutex, null);
   }
 
-  @VisibleForTesting
-  static class SynchronizedBiMap<K extends @Nullable Object, V extends @Nullable Object>
+  static final class SynchronizedBiMap<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedMap<K, V> implements BiMap<K, V>, Serializable {
     @CheckForNull private transient Set<V> valueSet;
     @RetainedWith @CheckForNull private transient BiMap<V, K> inverse;
@@ -1250,7 +1248,7 @@ public BiMap<V, K> inverse() {
     private static final long serialVersionUID = 0;
   }
 
-  private static class SynchronizedAsMap<K extends @Nullable Object, V extends @Nullable Object>
+  static final class SynchronizedAsMap<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedMap<K, Collection<V>> {
     @CheckForNull transient Set<Map.Entry<K, Collection<V>>> asMapEntrySet;
     @CheckForNull transient Collection<Collection<V>> asMapValues;
@@ -1297,7 +1295,7 @@ public boolean containsValue(@CheckForNull Object o) {
     private static final long serialVersionUID = 0;
   }
 
-  private static class SynchronizedAsMapValues<V extends @Nullable Object>
+  static final class SynchronizedAsMapValues<V extends @Nullable Object>
       extends SynchronizedCollection<Collection<V>> {
     SynchronizedAsMapValues(Collection<Collection<V>> delegate, @CheckForNull Object mutex) {
       super(delegate, mutex);
@@ -1319,8 +1317,8 @@ Collection<V> transform(Collection<V> from) {
 
   @GwtIncompatible // NavigableSet
   @VisibleForTesting
-  static class SynchronizedNavigableSet<E extends @Nullable Object> extends SynchronizedSortedSet<E>
-      implements NavigableSet<E> {
+  static final class SynchronizedNavigableSet<E extends @Nullable Object>
+      extends SynchronizedSortedSet<E> implements NavigableSet<E> {
     SynchronizedNavigableSet(NavigableSet<E> delegate, @CheckForNull Object mutex) {
       super(delegate, mutex);
     }
@@ -1463,7 +1461,8 @@ public SortedSet<E> tailSet(E fromElement) {
 
   @GwtIncompatible // NavigableMap
   @VisibleForTesting
-  static class SynchronizedNavigableMap<K extends @Nullable Object, V extends @Nullable Object>
+  static final class SynchronizedNavigableMap<
+          K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedSortedMap<K, V> implements NavigableMap<K, V> {
 
     SynchronizedNavigableMap(NavigableMap<K, V> delegate, @CheckForNull Object mutex) {
@@ -1664,7 +1663,7 @@ Map.Entry<K, V> nullableSynchronizedEntry(
   }
 
   @GwtIncompatible // works but is needed only for NavigableMap
-  private static class SynchronizedEntry<K extends @Nullable Object, V extends @Nullable Object>
+  static final class SynchronizedEntry<K extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedObject implements Map.Entry<K, V> {
 
     SynchronizedEntry(Map.Entry<K, V> delegate, @CheckForNull Object mutex) {
@@ -1719,8 +1718,8 @@ public V setValue(V value) {
     return (queue instanceof SynchronizedQueue) ? queue : new SynchronizedQueue<E>(queue, mutex);
   }
 
-  private static class SynchronizedQueue<E extends @Nullable Object>
-      extends SynchronizedCollection<E> implements Queue<E> {
+  static class SynchronizedQueue<E extends @Nullable Object> extends SynchronizedCollection<E>
+      implements Queue<E> {
 
     SynchronizedQueue(Queue<E> delegate, @CheckForNull Object mutex) {
       super(delegate, mutex);
@@ -1775,8 +1774,8 @@ public E remove() {
     return new SynchronizedDeque<E>(deque, mutex);
   }
 
-  private static final class SynchronizedDeque<E extends @Nullable Object>
-      extends SynchronizedQueue<E> implements Deque<E> {
+  static final class SynchronizedDeque<E extends @Nullable Object> extends SynchronizedQueue<E>
+      implements Deque<E> {
 
     SynchronizedDeque(Deque<E> delegate, @CheckForNull Object mutex) {
       super(delegate, mutex);
@@ -1918,7 +1917,7 @@ Table<R, C, V> table(Table<R, C, V> table, @CheckForNull Object mutex) {
     return new SynchronizedTable<>(table, mutex);
   }
 
-  private static final class SynchronizedTable<
+  static final class SynchronizedTable<
           R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object>
       extends SynchronizedObject implements Table<R, C, V> {
 

android/guava/src/com/google/common/collect/Tables.java

@@ -602,7 +602,7 @@ RowSortedTable<R, C, V> unmodifiableRowSortedTable(
     return new UnmodifiableRowSortedMap<>(table);
   }
 
-  static final class UnmodifiableRowSortedMap<
+  private static final class UnmodifiableRowSortedMap<
           R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object>
       extends UnmodifiableTable<R, C, V> implements RowSortedTable<R, C, V> {
 

android/guava/src/com/google/common/io/BaseEncoding.java

@@ -433,7 +433,7 @@ public static BaseEncoding base16() {
     return BASE16;
   }
 
-  private static final class Alphabet {
+  static final class Alphabet {
     private final String name;
     // this is meant to be immutable -- don't modify it!
     private final char[] chars;

guava/src/com/google/common/base/MoreObjects.java

@@ -439,7 +439,7 @@ private ToStringHelper addUnconditionalHolder(String name, Object value) {
     }
 
     // Holder object for values that might be null and/or empty.
-    private static class ValueHolder {
+    static class ValueHolder {
       @CheckForNull String name;
       @CheckForNull Object value;
       @CheckForNull ValueHolder next;

guava/src/com/google/common/collect/AbstractMapBasedMultimap.java

@@ -1063,7 +1063,7 @@ public SortedSet<K> tailSet(@ParametricNullness K fromElement) {
   }
 
   @WeakOuter
-  class NavigableKeySet extends SortedKeySet implements NavigableSet<K> {
+  private final class NavigableKeySet extends SortedKeySet implements NavigableSet<K> {
     NavigableKeySet(NavigableMap<K, Collection<V>> subMap) {
       super(subMap);
     }
@@ -1552,7 +1552,7 @@ SortedSet<K> createKeySet() {
     }
   }
 
-  class NavigableAsMap extends SortedAsMap implements NavigableMap<K, Collection<V>> {
+  private final class NavigableAsMap extends SortedAsMap implements NavigableMap<K, Collection<V>> {
 
     NavigableAsMap(NavigableMap<K, Collection<V>> submap) {
       super(submap);

guava/src/com/google/common/collect/HashBiMap.java

@@ -90,7 +90,7 @@ public final class HashBiMap<K extends @Nullable Object, V extends @Nullable Obj
     return bimap;
   }
 
-  private static final class BiEntry<K extends @Nullable Object, V extends @Nullable Object>
+  static final class BiEntry<K extends @Nullable Object, V extends @Nullable Object>
       extends ImmutableEntry<K, V> {
     final int keyHash;
     final int valueHash;
@@ -438,7 +438,7 @@ public int size() {
     return size;
   }
 
-  abstract class Itr<T extends @Nullable Object> implements Iterator<T> {
+  private abstract class Itr<T extends @Nullable Object> implements Iterator<T> {
     @CheckForNull BiEntry<K, V> next = firstInKeyInsertionOrder;
     @CheckForNull BiEntry<K, V> toRemove = null;
     int expectedModCount = modCount;
@@ -531,7 +531,7 @@ Entry<K, V> output(BiEntry<K, V> entry) {
       }
 
       class MapEntry extends AbstractMapEntry<K, V> {
-        BiEntry<K, V> delegate;
+        private BiEntry<K, V> delegate;
 
         MapEntry(BiEntry<K, V> entry) {
           this.delegate = entry;
@@ -708,7 +708,7 @@ Entry<V, K> output(BiEntry<K, V> entry) {
         }
 
         class InverseEntry extends AbstractMapEntry<V, K> {
-          BiEntry<K, V> delegate;
+          private BiEntry<K, V> delegate;
 
           InverseEntry(BiEntry<K, V> entry) {
             this.delegate = entry;

guava/src/com/google/common/collect/LinkedHashMultimap.java

@@ -193,11 +193,11 @@ static final class ValueEntry<K extends @Nullable Object, V extends @Nullable Ob
      * frameworks like Android that define post-construct hooks like Activity.onCreate, etc.
      */
 
-    @CheckForNull ValueSetLink<K, V> predecessorInValueSet;
-    @CheckForNull ValueSetLink<K, V> successorInValueSet;
+    @CheckForNull private ValueSetLink<K, V> predecessorInValueSet;
+    @CheckForNull private ValueSetLink<K, V> successorInValueSet;
 
-    @CheckForNull ValueEntry<K, V> predecessorInMultimap;
-    @CheckForNull ValueEntry<K, V> successorInMultimap;
+    @CheckForNull private ValueEntry<K, V> predecessorInMultimap;
+    @CheckForNull private ValueEntry<K, V> successorInMultimap;
 
     ValueEntry(
         @ParametricNullness K key,

guava/src/com/google/common/collect/LinkedListMultimap.java

@@ -107,7 +107,7 @@ public class LinkedListMultimap<K extends @Nullable Object, V extends @Nullable
    * ValueForKeyIterator} in constant time.
    */
 
-  private static final class Node<K extends @Nullable Object, V extends @Nullable Object>
+  static final class Node<K extends @Nullable Object, V extends @Nullable Object>
       extends AbstractMapEntry<K, V> {
     @ParametricNullness final K key;
     @ParametricNullness V value;

guava/src/com/google/common/collect/MinMaxPriorityQueue.java

@@ -521,7 +521,7 @@ boolean isIntact() {
    * sake they are stored interleaved on alternate heap levels in the same array (MMPQ.queue).
    */
   @WeakOuter
-  private class Heap {
+  class Heap {
     final Ordering<E> ordering;
 
     @SuppressWarnings("nullness:initialization.field.uninitialized")

guava/src/com/google/common/collect/StandardTable.java

@@ -846,7 +846,7 @@ protected Set<Entry<R, Map<C, V>>> createEntrySet() {
     }
 
     @WeakOuter
-    class EntrySet extends TableSet<Entry<R, Map<C, V>>> {
+    private final class EntrySet extends TableSet<Entry<R, Map<C, V>>> {
       @Override
       public Iterator<Entry<R, Map<C, V>>> iterator() {
         return Maps.asMapEntryIterator(
@@ -935,7 +935,7 @@ Collection<Map<R, V>> createValues() {
     }
 
     @WeakOuter
-    class ColumnMapEntrySet extends TableSet<Entry<C, Map<R, V>>> {
+    private final class ColumnMapEntrySet extends TableSet<Entry<C, Map<R, V>>> {
       @Override
       public Iterator<Entry<C, Map<R, V>>> iterator() {
         return Maps.asMapEntryIterator(