Is there a concurrent List in Java's JDK?

Delving into the details: Concurrent Collection types

Java provides a variety of concurrent collections each with their own strengths suited to different scenarios.

The Concurrent Queue Kingdom

When you have a multithreaded queue scenario with high throughput, ConcurrentLinkedQueue and ConcurrentLinkedDeque offer excellent insertion-order maintenance and fast operations.

Queue<String> concurrentQueue = new ConcurrentLinkedQueue<>();
concurrentQueue.add("Java"); // Adding elements faster than a caffeinated coder
concurrentQueue.add("Concurrency");
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Block the Queue, Not the Fun

In producer-consumer situations, where the producer and consumer don't see eye to eye on speed, ArrayBlockingQueue and LinkedBlockingQueue can come to the rescue, providing blocking operations that wait patiently for the operations to complete.

BlockingQueue<String> blockingQueue = new ArrayBlockingQueue<>(1024);
blockingQueue.put("Producer data"); // Producer producing like there's no tomorrow
String consumerData = blockingQueue.take(); // The consumer can relax till the data arrives
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DIY: Building Custom Concurrent Structures

Occasionally we may have peculiar requirements that call for a custom solution that might use ReentrantLock or other locking mechanisms to ensure consistency.

Lock lock = new ReentrantLock(); // Putting a lock on things like a possessive lover
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Thread-safe Merry-go-round: Sets and Maps

For situations involving sets or maps, CopyOnWriteArraySet and ConcurrentHashMap can come to your aid, providing high levels of concurrency and performance.

Set<String> concurrentSet = new CopyOnWriteArraySet<>();
concurrentSet.add("Hello"); // Keeps duplicates away like an enforced restraining order
Map<String, String> concurrentMap = new ConcurrentHashMap<>();
concurrentMap.put("Key", "Value"); // It's all about the keys, no trouble
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Advanced tools in Concurrency toolkit

Java also equips you with structures and utilities to address more complex scenarios and craft high-performance solutions.

Atomic Integer & References to the rescue

Atomic utilities like AtomicInteger or AtomicReference can combine with concurrent collections to manage complex atomic operations without explicit locks.

AtomicInteger atomicCounter = new AtomicInteger(); // Counting without losing count
atomicCounter.incrementAndGet(); // I increment therefore I am
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Blaze through the list

CopyOnWriteArrayList permits safe iterations with the traditional for loop, remaining immune to ConcurrentModificationException even when modified during iteration. Time to bid a fond farewell to those annoying exceptions! 🎉

for (String item : safeList) { 
    System.out.println(item); // This loop won't break your heart
}
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Without the lock, but with love

You can iterate over ConcurrentLinkedQueue without explicit locks, keeping performance high.

for (String item : concurrentQueue) {
    System.out.println(item); // Smoothly cruising through items
}
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