Internal change

RELNOTES=n/a
PiperOrigin-RevId: 869448999

Author: java-team-github-bot

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

@@ -17,13 +17,15 @@
 package com.google.common.collect;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.collect.NullnessCasts.uncheckedCastNullableTToT;
 import static java.util.Collections.emptyList;
 
 import com.google.common.annotations.GwtCompatible;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.NoSuchElementException;
 import java.util.Optional;
+import java.util.function.Supplier;
 import java.util.stream.Collector;
 import org.jspecify.annotations.Nullable;
 
@@ -44,7 +46,7 @@ public final class MoreCollectors {
    */
   private static final Collector<Object, ?, Optional<Object>> TO_OPTIONAL =
       Collector.of(
-          ToOptionalState::new,
+          () -> new ToOptionalState<>(null),
           ToOptionalState::add,
           ToOptionalState::combine,
           ToOptionalState::getOptional,
@@ -66,8 +68,8 @@ public final class MoreCollectors {
   private static final Object NULL_PLACEHOLDER = new Object();
 
   private static final Collector<@Nullable Object, ?, @Nullable Object> ONLY_ELEMENT =
-      Collector.<@Nullable Object, ToOptionalState, @Nullable Object>of(
-          ToOptionalState::new,
+      Collector.<@Nullable Object, ToOptionalState<Object>, @Nullable Object>of(
+          () -> new ToOptionalState<>(null),
           (state, o) -> state.add((o == null) ? NULL_PLACEHOLDER : o),
           ToOptionalState::combine,
           state -> {
@@ -91,18 +93,24 @@ public final class MoreCollectors {
    * than one, not just two.
    */
   @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
-  private static final class ToOptionalState {
+  @IgnoreJRERequirement // see enclosing class (whose annotation Animal Sniffer ignores here...)
+  private static final class ToOptionalState<T> {
     static final int MAX_EXTRAS = 4;
 
-    @Nullable Object element;
-    List<Object> extras;
+    @Nullable T element;
+    List<T> extras;
+    final @Nullable Supplier<? extends RuntimeException> exceptionSupplier;
 
-    ToOptionalState() {
-      element = null;
-      extras = emptyList();
+    ToOptionalState(@Nullable Supplier<? extends RuntimeException> exceptionSupplier) {
+      this.element = null;
+      this.extras = emptyList();
+      this.exceptionSupplier = exceptionSupplier;
     }
 
-    IllegalArgumentException multiples(boolean overflow) {
+    RuntimeException multiples(boolean overflow) {
+      if (exceptionSupplier != null) {
+        throw exceptionSupplier.get();
+      }
       StringBuilder sb =
           new StringBuilder().append("expected one element but was: <").append(element);
       for (Object o : extras) {
@@ -115,7 +123,7 @@ IllegalArgumentException multiples(boolean overflow) {
       throw new IllegalArgumentException(sb.toString());
     }
 
-    void add(Object o) {
+    void add(T o) {
       checkNotNull(o);
       if (element == null) {
         this.element = o;
@@ -130,7 +138,7 @@ void add(Object o) {
       }
     }
 
-    ToOptionalState combine(ToOptionalState other) {
+    ToOptionalState<T> combine(ToOptionalState<T> other) {
       if (element == null) {
         return other;
       } else if (other.element == null) {
@@ -151,19 +159,23 @@ ToOptionalState combine(ToOptionalState other) {
     }
 
     @IgnoreJRERequirement // see enclosing class (whose annotation Animal Sniffer ignores here...)
-    Optional<Object> getOptional() {
+    Optional<T> getOptional() {
       if (extras.isEmpty()) {
         return Optional.ofNullable(element);
       } else {
         throw multiples(false);
       }
     }
 
-    Object getElement() {
+    T getElement() {
       if (element == null) {
-        throw new NoSuchElementException();
+        if (exceptionSupplier != null) {
+          throw exceptionSupplier.get();
+        } else {
+          throw new NoSuchElementException();
+        }
       } else if (extras.isEmpty()) {
-        return element;
+        return uncheckedCastNullableTToT(element);
       } else {
         throw multiples(false);
       }

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

@@ -17,13 +17,15 @@
 package com.google.common.collect;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.collect.NullnessCasts.uncheckedCastNullableTToT;
 import static java.util.Collections.emptyList;
 
 import com.google.common.annotations.GwtCompatible;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.NoSuchElementException;
 import java.util.Optional;
+import java.util.function.Supplier;
 import java.util.stream.Collector;
 import org.jspecify.annotations.Nullable;
 
@@ -43,7 +45,7 @@ public final class MoreCollectors {
    */
   private static final Collector<Object, ?, Optional<Object>> TO_OPTIONAL =
       Collector.of(
-          ToOptionalState::new,
+          () -> new ToOptionalState<>(null),
           ToOptionalState::add,
           ToOptionalState::combine,
           ToOptionalState::getOptional,
@@ -65,8 +67,8 @@ public final class MoreCollectors {
   private static final Object NULL_PLACEHOLDER = new Object();
 
   private static final Collector<@Nullable Object, ?, @Nullable Object> ONLY_ELEMENT =
-      Collector.<@Nullable Object, ToOptionalState, @Nullable Object>of(
-          ToOptionalState::new,
+      Collector.<@Nullable Object, ToOptionalState<Object>, @Nullable Object>of(
+          () -> new ToOptionalState<>(null),
           (state, o) -> state.add((o == null) ? NULL_PLACEHOLDER : o),
           ToOptionalState::combine,
           state -> {
@@ -90,18 +92,24 @@ public final class MoreCollectors {
    * than one, not just two.
    */
   @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
-  private static final class ToOptionalState {
+  @IgnoreJRERequirement // see enclosing class (whose annotation Animal Sniffer ignores here...)
+  private static final class ToOptionalState<T> {
     static final int MAX_EXTRAS = 4;
 
-    @Nullable Object element;
-    List<Object> extras;
+    @Nullable T element;
+    List<T> extras;
+    final @Nullable Supplier<? extends RuntimeException> exceptionSupplier;
 
-    ToOptionalState() {
-      element = null;
-      extras = emptyList();
+    ToOptionalState(@Nullable Supplier<? extends RuntimeException> exceptionSupplier) {
+      this.element = null;
+      this.extras = emptyList();
+      this.exceptionSupplier = exceptionSupplier;
     }
 
-    IllegalArgumentException multiples(boolean overflow) {
+    RuntimeException multiples(boolean overflow) {
+      if (exceptionSupplier != null) {
+        throw exceptionSupplier.get();
+      }
       StringBuilder sb =
           new StringBuilder().append("expected one element but was: <").append(element);
       for (Object o : extras) {
@@ -114,7 +122,7 @@ IllegalArgumentException multiples(boolean overflow) {
       throw new IllegalArgumentException(sb.toString());
     }
 
-    void add(Object o) {
+    void add(T o) {
       checkNotNull(o);
       if (element == null) {
         this.element = o;
@@ -129,7 +137,7 @@ void add(Object o) {
       }
     }
 
-    ToOptionalState combine(ToOptionalState other) {
+    ToOptionalState<T> combine(ToOptionalState<T> other) {
       if (element == null) {
         return other;
       } else if (other.element == null) {
@@ -149,19 +157,23 @@ ToOptionalState combine(ToOptionalState other) {
       }
     }
 
-    Optional<Object> getOptional() {
+    Optional<T> getOptional() {
       if (extras.isEmpty()) {
         return Optional.ofNullable(element);
       } else {
         throw multiples(false);
       }
     }
 
-    Object getElement() {
+    T getElement() {
       if (element == null) {
-        throw new NoSuchElementException();
+        if (exceptionSupplier != null) {
+          throw exceptionSupplier.get();
+        } else {
+          throw new NoSuchElementException();
+        }
       } else if (extras.isEmpty()) {
-        return element;
+        return uncheckedCastNullableTToT(element);
       } else {
         throw multiples(false);
       }