System.setProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS, testAddress);
            String result = SystemUtil.getSearchEngineHttpAddress();
            assertEquals(testAddress, result); // Should return exactly what's in the property
        } finally {
            // Restore original value
            if (originalValue != null) {
                System.setProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS, originalValue);

        byte[] dst = new byte[2];
        int written = instance.writeParameterWordsWireFormat(dst, 0);
        assertEquals(2, written, "writeParameterWordsWireFormat should write exactly 2 bytes");
        // SMBUtil.writeInt2 writes the low byte first (little‑endian)
        assertEquals((byte) (TEST_SID & 0xFF), dst[0]);
        assertEquals((byte) ((TEST_SID >> 8) & 0xFF), dst[1]);
    }

    @Test

   * #notifyFailed(Throwable)} instead.
   *
   * <p>This method should return promptly; prefer to do work on a different thread where it is
   * convenient. It is invoked exactly once on service startup, even when {@link #startAsync} is
   * called multiple times.
   */
  @ForOverride
  protected abstract void doStart();

  /**

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization

   *
   * <ul>
   *   <li>Both {@code xStats} and {@code yStats} must have the same {@code count}.
   *   <li>If that {@code count} is 1, {@code sumOfProductsOfDeltas} must be exactly 0.0.
   *   <li>If that {@code count} is more than 1, {@code sumOfProductsOfDeltas} must be finite.
   * </ul>
   */
  PairedStats(Stats xStats, Stats yStats, double sumOfProductsOfDeltas) {
    this.xStats = xStats;

        assertTrue(DosError.DOS_ERROR_CODES.length > 0, "DOS_ERROR_CODES should contain at least one mapping");
    }

    @Test
    @DisplayName("Each error code mapping contains exactly two ints")
    void testEachPairLength() {
        for (int i = 0; i < DosError.DOS_ERROR_CODES.length; i++) {
            int[] pair = DosError.DOS_ERROR_CODES[i];

## Password hashing { #password-hashing }

"Hashing" means converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

### Why use password hashing { #why-use-password-hashing }

   * suitable for your application, see <a
   * href="https://github.com/google/guava/wiki/InternetDomainNameExplained">this article</a>.
   *
   * @return {@code true} if this domain name appears exactly on the public suffix list
   * @since 6.0
   */
  public boolean isPublicSuffix() {
    return publicSuffixIndex() == 0;
  }

  /**

                .filter(f -> Modifier.isStatic(f.getModifiers()))
                .filter(f -> Modifier.isFinal(f.getModifiers()))
                .count();

        assertEquals(8, constantCount, "Should have exactly 8 constant fields");
    }

    @Test
    @DisplayName("Test constant naming convention")
    void testConstantNamingConvention() {
        Field[] fields = SecurityInfo.class.getDeclaredFields();

import com.google.j2objc.annotations.RetainedWith;
import java.util.function.BiConsumer;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableMap} with exactly one entry.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization