@CanIgnoreReturnValue
  private static Thread acquireFor(Lock lock, long duration, TimeUnit unit) {
    CountDownLatch latch = new CountDownLatch(1);
    Thread thread =
        new Thread() {
          @Override
          public void run() {
            lock.lock();
            latch.countDown();
            try {
              Thread.sleep(unit.toMillis(duration));
            } catch (InterruptedException e) {

import com.google.common.collect.testing.google.TestStringBiMapGenerator;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;

/**
 * Tests for {@link HashBiMap}.
 *
 * @author Mike Bostock
 */
@GwtCompatible
@NullMarked

 */
package org.codelibs.fess.util;

import static org.junit.Assert.assertArrayEquals;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.codelibs.fess.unit.UnitFessTestCase;

public class DocumentUtilTest extends UnitFessTestCase {

    public void test_string() {

import static com.google.common.truth.TruthJUnit.assume;
import static org.junit.Assert.assertThrows;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import com.google.common.collect.ImmutableSet;
import com.google.common.testing.EqualsTester;
import java.util.Set;
import org.jspecify.annotations.NullUnmarked;
import org.junit.After;
import org.junit.Test;

/**

import static java.util.concurrent.TimeUnit.SECONDS;
import static org.junit.Assert.assertThrows;

import com.google.common.cache.CacheLoader.InvalidCacheLoadException;
import com.google.common.cache.TestingRemovalListeners.QueuingRemovalListener;
import com.google.common.util.concurrent.UncheckedExecutionException;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

import static com.google.common.io.TestOption.OPEN_THROWS;
import static com.google.common.io.TestOption.READ_THROWS;
import static com.google.common.io.TestOption.WRITE_THROWS;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertThrows;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.EnumSet;
import org.jspecify.annotations.NullUnmarked;

import static com.google.common.util.concurrent.Uninterruptibles.joinUninterruptibly;
import static org.junit.Assert.assertThrows;

import com.google.common.util.concurrent.GeneratedMonitorTest.FlagGuard;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

import static java.util.concurrent.TimeUnit.SECONDS;
import static org.junit.Assert.assertThrows;

import com.google.common.cache.CacheLoader.InvalidCacheLoadException;
import com.google.common.cache.TestingRemovalListeners.QueuingRemovalListener;
import com.google.common.util.concurrent.UncheckedExecutionException;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

import static com.google.common.io.TestOption.OPEN_THROWS;
import static com.google.common.io.TestOption.READ_THROWS;
import static com.google.common.io.TestOption.WRITE_THROWS;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertThrows;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.EnumSet;
import org.jspecify.annotations.NullUnmarked;

import static com.google.common.util.concurrent.Uninterruptibles.joinUninterruptibly;
import static org.junit.Assert.assertThrows;

import com.google.common.util.concurrent.GeneratedMonitorTest.FlagGuard;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**