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

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 10  *
 11  * This code is distributed in the hope that it will be useful, but WITHOUT
 12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 14  * version 2 for more details (a copy is included in the LICENSE file that
 15  * accompanied this code).
 16  *
 17  * You should have received a copy of the GNU General Public License version
 18  * 2 along with this work; if not, write to the Free Software Foundation,
 19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 20  *
 21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 22  * or visit www.oracle.com if you need additional information or have any
 23  * questions.
 24  */
 25 
 26 package java.util;
 27 
 28 import jdk.internal.util.Preconditions;
 29 import jdk.internal.vm.annotation.ForceInline;

 30 
 31 import java.util.function.Supplier;
 32 
 33 /**
 34  * This class consists of {@code static} utility methods for operating
 35  * on objects, or checking certain conditions before operation.  These utilities
 36  * include {@code null}-safe or {@code null}-tolerant methods for computing the
 37  * hash code of an object, returning a string for an object, comparing two
 38  * objects, and checking if indexes or sub-range values are out of bounds.
 39  *
 40  * @since 1.7
 41  */
 42 public final class Objects {
 43     private Objects() {
 44         throw new AssertionError("No java.util.Objects instances for you!");
 45     }
 46 
 47     /**
 48      * Returns {@code true} if the arguments are equal to each other
 49      * and {@code false} otherwise.

420      * inequalities is true:
421      * <ul>
422      *  <li>{@code fromIndex < 0}</li>
423      *  <li>{@code size < 0}</li>
424      *  <li>{@code fromIndex + size > length}, taking into account integer overflow</li>
425      *  <li>{@code length < 0}, which is implied from the former inequalities</li>
426      * </ul>
427      *
428      * @param fromIndex the lower-bound (inclusive) of the sub-interval
429      * @param size the size of the sub-range
430      * @param length the upper-bound (exclusive) of the range
431      * @return {@code fromIndex} if the sub-range within bounds of the range
432      * @throws IndexOutOfBoundsException if the sub-range is out of bounds
433      * @since 9
434      */
435     public static
436     int checkFromIndexSize(int fromIndex, int size, int length) {
437         return Preconditions.checkFromIndexSize(fromIndex, size, length, null);
438     }
439 











440     /**
441      * Checks if the {@code index} is within the bounds of the range from
442      * {@code 0} (inclusive) to {@code length} (exclusive).
443      *
444      * <p>The {@code index} is defined to be out of bounds if any of the
445      * following inequalities is true:
446      * <ul>
447      *  <li>{@code index < 0}</li>
448      *  <li>{@code index >= length}</li>
449      *  <li>{@code length < 0}, which is implied from the former inequalities</li>
450      * </ul>
451      *
452      * @param index the index
453      * @param length the upper-bound (exclusive) of the range
454      * @return {@code index} if it is within bounds of the range
455      * @throws IndexOutOfBoundsException if the {@code index} is out of bounds
456      * @since 16
457      */
458     @ForceInline
459     public static

 10  *
 11  * This code is distributed in the hope that it will be useful, but WITHOUT
 12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 14  * version 2 for more details (a copy is included in the LICENSE file that
 15  * accompanied this code).
 16  *
 17  * You should have received a copy of the GNU General Public License version
 18  * 2 along with this work; if not, write to the Free Software Foundation,
 19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 20  *
 21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 22  * or visit www.oracle.com if you need additional information or have any
 23  * questions.
 24  */
 25 
 26 package java.util;
 27 
 28 import jdk.internal.util.Preconditions;
 29 import jdk.internal.vm.annotation.ForceInline;
 30 import jdk.internal.misc.Unsafe;
 31 
 32 import java.util.function.Supplier;
 33 
 34 /**
 35  * This class consists of {@code static} utility methods for operating
 36  * on objects, or checking certain conditions before operation.  These utilities
 37  * include {@code null}-safe or {@code null}-tolerant methods for computing the
 38  * hash code of an object, returning a string for an object, comparing two
 39  * objects, and checking if indexes or sub-range values are out of bounds.
 40  *
 41  * @since 1.7
 42  */
 43 public final class Objects {
 44     private Objects() {
 45         throw new AssertionError("No java.util.Objects instances for you!");
 46     }
 47 
 48     /**
 49      * Returns {@code true} if the arguments are equal to each other
 50      * and {@code false} otherwise.

421      * inequalities is true:
422      * <ul>
423      *  <li>{@code fromIndex < 0}</li>
424      *  <li>{@code size < 0}</li>
425      *  <li>{@code fromIndex + size > length}, taking into account integer overflow</li>
426      *  <li>{@code length < 0}, which is implied from the former inequalities</li>
427      * </ul>
428      *
429      * @param fromIndex the lower-bound (inclusive) of the sub-interval
430      * @param size the size of the sub-range
431      * @param length the upper-bound (exclusive) of the range
432      * @return {@code fromIndex} if the sub-range within bounds of the range
433      * @throws IndexOutOfBoundsException if the sub-range is out of bounds
434      * @since 9
435      */
436     public static
437     int checkFromIndexSize(int fromIndex, int size, int length) {
438         return Preconditions.checkFromIndexSize(fromIndex, size, length, null);
439     }
440 
441     /**
442      * Return the size of the object in the heap.
443      *
444      * @param o an object
445      * @return the objects's size
446      * @since Valhalla
447      */
448     public static long getObjectSize(Object o) {
449         return Unsafe.getUnsafe().getObjectSize(o);
450     }
451 
452     /**
453      * Checks if the {@code index} is within the bounds of the range from
454      * {@code 0} (inclusive) to {@code length} (exclusive).
455      *
456      * <p>The {@code index} is defined to be out of bounds if any of the
457      * following inequalities is true:
458      * <ul>
459      *  <li>{@code index < 0}</li>
460      *  <li>{@code index >= length}</li>
461      *  <li>{@code length < 0}, which is implied from the former inequalities</li>
462      * </ul>
463      *
464      * @param index the index
465      * @param length the upper-bound (exclusive) of the range
466      * @return {@code index} if it is within bounds of the range
467      * @throws IndexOutOfBoundsException if the {@code index} is out of bounds
468      * @since 16
469      */
470     @ForceInline
471     public static
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