import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;
import org.jspecify.annotations.Nullable;

/**
 * A multiset that supports concurrent modifications and that provides atomic versions of most

       *   to iterate it to exhaustion. Then we can apply the logic above about an empty
       *   columnIterator. (This assumes no concurrent modification, but behavior under concurrent
       *   modification is undefined, anyway.)
       */
      requireNonNull(rowEntry);
      Entry<C, V> columnEntry = columnIterator.next();

 * the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import com.google.errorprone.annotations.concurrent.GuardedBy;
import java.util.ArrayDeque;
import java.util.ArrayList;

 * limitations under the License.
 */
package okhttp3

import java.util.ArrayDeque
import java.util.concurrent.ExecutorService
import java.util.concurrent.SynchronousQueue
import java.util.concurrent.ThreadPoolExecutor
import java.util.concurrent.TimeUnit
import okhttp3.internal.assertLockNotHeld
import okhttp3.internal.connection.RealCall
import okhttp3.internal.connection.RealCall.AsyncCall

package org.apache.maven.graph;

import java.util.ArrayList;
import java.util.Collection;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.maven.execution.ProjectDependencyGraph;
import org.apache.maven.project.MavenProject;

/**
 * Provides a sub view of another dependency graph.
 *
 */

        return parentLeaseKey != null;
    }
}
```

### 4.3 Lease Manager
```java
package jcifs.internal.smb2.lease;

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import jcifs.CIFSContext;

public class LeaseManager {
    private final ConcurrentHashMap<Smb2LeaseKey, LeaseEntry> leases;

import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReferenceArray;
import java.util.logging.LogRecord;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

            }
        }
        return OptionalEntity.empty();
    }

    /**
     * Stores or updates a dictionary file in the ConfigSync storage.
     * This method checks for concurrent modifications by comparing timestamps
     * and uploads the file content to the ConfigSync API.
     *
     * @param dictFile the dictionary file metadata to store

            return "Release existing locks or wait for them to be released";
        case BUFFER:
            return "Reduce buffer usage or increase buffer pool size";
        case THREAD_POOL:
            return "Reduce concurrent operations or increase thread pool size";
        default:
            return "Check resource availability and retry";
        }
    }

    /**
     * Static factory for file handle exhaustion
     */

import com.google.common.collect.ImmutableMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutionException;

/**
 * This class provides a skeletal implementation of the {@code Cache} interface to minimize the
 * effort required to implement this interface.
 *