src/java.base/share/classes/java/util/Optional.java

rev 14279 : [mq]: 8140281-deprecation-optional.get

*** 124,141 ****
--- 124,173 ----
      public static <T> Optional<T> ofNullable(T value) {
          return value == null ? empty() : of(value);
      }
  
      /**
+      * Equivalent to {@link #getWhenPresent()}.
       * If a value is present, returns the value, otherwise throws
       * {@code NoSuchElementException}.
       *
+      * @deprecated
+      * This method's simple name {@code get} makes it the obvious method to
+      * call to retrieve the value from this {@code Optional}. However, it has
+      * no mechanism to avoid an exception if this {@code Optional} is empty.
+      * This tends to lead to code that mishandles empty {@code Optional}
+      * values. Consider using other methods that handle the case where
+      * the {@code Optional} might be empty, such as
+      * {@link #filter(java.util.function.Predicate) filter()},
+      * {@link #map(java.util.function.Function) map()},
+      * {@link #ifPresent(java.util.function.Consumer) ifPresent()}
+      * and related methods, and
+      * {@link #orElse(java.lang.Object) orElse()} and related methods.
+      * Use {@link getWhenPresent()} when it is known that a value is
+      * always present.
+      *
       * @return the non-{@code null} value described by this {@code Optional}
       * @throws NoSuchElementException if no value is present
       * @see Optional#isPresent()
       */
+     @Deprecated(since="9")
      public T get() {
+         return getWhenPresent();
+     }
+ 
+     /**
+      * If a value is present, returns the value, otherwise throws
+      * {@code NoSuchElementException}.
+      *
+      * @apiNote
+      * Use this method only when it is known that a value is always present.
+      *
+      * @return the non-{@code null} value described by this {@code Optional}
+      * @throws NoSuchElementException if no value is present
+      * @see Optional#isPresent()
+      */
+     public T getWhenPresent() {
          if (value == null) {
              throw new NoSuchElementException("No value present");
          }
          return value;
      }