import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.io.IOException;
import java.util.AbstractList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.jspecify.annotations.Nullable;

/**

   * @deprecated Unsupported operation.
   */
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public final boolean retainAll(Collection<?> elementsToKeep) {
    throw new UnsupportedOperationException();
  }

  /**
   * Guaranteed to throw an exception and leave the collection unmodified.
   *
   * @throws UnsupportedOperationException always

        // TODO(lowasser): avoid allocation here
        return Arrays.equals(toPlainArray(data), toPlainArray(lockFreeBitArray.data));
      }
      return false;
    }

    @Override
    public int hashCode() {
      // TODO(lowasser): avoid allocation here
      return Arrays.hashCode(toPlainArray(data));
    }
  }

            // Should only copy first 16 bytes
            assertArrayEquals(Arrays.copyOfRange(longFileId, 0, 16), Arrays.copyOfRange(buffer, 16, 32));
        }

        @Test
        @DisplayName("Should handle file ID shorter than 16 bytes")
        void testShortFileId() {
            byte[] shortFileId = new byte[8];
            Arrays.fill(shortFileId, (byte) 0xAB);
            request.setFileId(shortFileId);

import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.LongBuffer;
import java.nio.ShortBuffer;
import java.nio.charset.Charset;
import java.util.ArrayDeque;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Currency;
import java.util.Deque;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;

        assertEquals("0A0B0C", Hexdump.toHexString(data3, 0, 6)); // 6 chars = 3 bytes

        // Test with offset - NOTE: srcIndex is ignored due to bug, it always starts from index 0
        byte[] data4 = { 0x00, 0x11, 0x22, 0x33, 0x44 };
        assertEquals("00", Hexdump.toHexString(data4, 1, 2)); // Bug: ignores srcIndex, reads from 0

            for (final StackTraceElement[] acq : this.acquires) {
                log.debug("Acquire " + Arrays.toString(acq));
            }
        }

        synchronized (this.releases) {
            for (final StackTraceElement[] rel : this.releases) {
                log.debug("Release " + Arrays.toString(rel));
            }
        }
    }

    @Override
    public String toString() {

import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.testers.ReflectionFreeAssertThrows.assertThrows;
import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;

      } else if (read1 != BUFFER_SIZE) {
        return true;
      }
    }
  }

  // The Arrays.equals(<arraytype>, int, int, <arraytype>, int, int) methods were not added until
  // Java 9. This function is just returns the same result that
  // Arrays.equals(array1, 0, count, array2, 0, count) would. It assumes that both arrays have a
  // length of at least count.

It also re-declares `id: int`. By doing this, we are making a **contract** with the API clients, so that they can always expect the `id` to be there and to be an `int` (it will never be `None`).

/// tip

Having the return model ensure that a value is always available and always `int` (not `None`) is very useful for the API clients, they can write much simpler code having this certainty.