LocalCache<Object, Object> map = makeLocalCache(builder);

      Object keyOne = new Object();
      Object valueOne = new Object();
      int hashOne = map.hash(keyOne);
      ReferenceEntry<Object, Object> entryOne = map.newEntry(keyOne, hashOne, null);
      ValueReference<Object, Object> valueRefOne = map.newValueReference(entryOne, valueOne, 1);
      assertThat(valueRefOne.get()).isSameInstanceAs(valueOne);

      LocalCache<Object, Object> map = makeLocalCache(builder);

      Object keyOne = new Object();
      Object valueOne = new Object();
      int hashOne = map.hash(keyOne);
      ReferenceEntry<Object, Object> entryOne = map.newEntry(keyOne, hashOne, null);
      ValueReference<Object, Object> valueRefOne = map.newValueReference(entryOne, valueOne, 1);
      assertThat(valueRefOne.get()).isSameInstanceAs(valueOne);

 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.collect.Hashing.smear;

import com.google.common.annotations.GwtCompatible;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;

/** Tests for {@code Hashing}. */
@GwtCompatible
@NullMarked
public class HashingTest extends TestCase {
  public void testSmear() {

 * little-endian order.
 *
 * <p><b>Warning:</b> The result of calling any methods after calling {@link #hash} is undefined.
 *
 * <p><b>Warning:</b> Using a specific character encoding when hashing a {@link CharSequence} with
 * {@link #putString(CharSequence, Charset)} is generally only useful for cross-language
 * compatibility (otherwise prefer {@link #putUnencodedChars}). However, the character encodings

 * (Modified to adapt to Guava coding conventions and to use the HashFunction interface)
 */

package com.google.common.hash;

import static com.google.common.hash.Hashing.GOOD_FAST_HASH_SEED;
import static java.lang.Byte.toUnsignedInt;

import com.google.errorprone.annotations.Immutable;
import java.io.Serializable;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

# OAuth2 с паролем (и хешированием), Bearer с JWT-токенами { #oauth2-with-password-and-hashing-bearer-with-jwt-tokens }

Теперь, когда у нас определен процесс обеспечения безопасности, давайте сделаем приложение действительно безопасным, используя токены <abbr title="JSON Web Tokens - веб‑токены JSON">JWT</abbr> и безопасное хеширование паролей.

Этот код можно реально использовать в своем приложении, сохранять хэши паролей в базе данных и т.д.

///

## 패스워드 해싱 { #password-hashing }

"해싱(Hashing)"은 어떤 내용(여기서는 패스워드)을 알아볼 수 없는 바이트 시퀀스(그냥 문자열)로 변환하는 것을 의미합니다.

정확히 같은 내용(정확히 같은 패스워드)을 넣으면 정확히 같은 알아볼 수 없는 문자열이 나옵니다.

하지만 그 알아볼 수 없는 문자열에서 다시 패스워드로 되돌릴 수는 없습니다.

### 패스워드 해싱을 사용하는 이유 { #why-use-password-hashing }

데이터베이스를 탈취당하더라도, 침입자는 사용자의 평문 패스워드 대신 해시만 얻게 됩니다.

import static java.lang.Long.rotateRight;

import com.google.common.annotations.VisibleForTesting;

/**
 * Implementation of Geoff Pike's fingerprint2011 hash function. See {@link Hashing#fingerprint2011}
 * for information on the behaviour of the algorithm.
 *
 * <p>On Intel Core2 2.66, on 1000 bytes, fingerprint2011 takes 0.9 microseconds compared to

import com.google.common.annotations.VisibleForTesting;

/**
 * Implementation of FarmHash Fingerprint64, an open-source fingerprinting algorithm for strings.
 *
 * <p>Its speed is comparable to CityHash64, and its quality of hashing is at least as good.
 *
 * <p>Note to maintainers: This implementation relies on signed arithmetic being bit-wise equivalent
 * to unsigned arithmetic in all cases except:
 *
 * <ul>

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import org.jspecify.annotations.Nullable;

/**
 * Multiset implementation that uses hashing for key and entry access.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class HashMultiset<E extends @Nullable Object> extends AbstractMapBasedMultiset<E> {