Posts about Java concurrent utils package. Concurrent collections. blocking queues, non-blocking queues, synchronizers.
CopyOnWriteArraySet in Java extends the AbstractSet which in turn implements the Set interface and is part of java.util.concurrent package. How CopyOnWriteArraySet differs from other Set implementations in Java Collections framework is that it is thread-safe. Table of contents CopyOnWriteArraySet internal implementation in Java Features of the CopyOnWriteArraySet Java CopyOnWriteArraySet constructors…
ConcurrentSkipListSet in Java is a sorted set just like TreeSet but it is also scalable and concurrent so ConcurrentSkipListSet is thread-safe and can be accessed by multiple threads safely. In ConcurrentSkipListSet operations like add and remove are done atomically using compare and swap (CAS). These are lock-free so overhead of…
This post talks about the ConcurrentSkipListMap class from the java.util.concurrent package and the interface ConcurrentNavigableMap this class implements. ConcurrentSkipListMap in Java ConcurrentSkipListMap is a thread-safe, scalable Map that stores its elements in sorted manner. By default map is sorted according to the natural ordering of its keys, or by a…
In this post we’ll see two of the interesting features of the concurrent API, Callable and Future in Java. Table of contents Callable in Java Callable interface Running a Callable task using ExecutorService Java Callable and Future example Future in Java Callable and Future example Callable in Java Consider a…
LinkedBlockingQueue in Java is an implementation of BlockingQueue interface and is part of java.util.concurrent package. LinkedBlockingQueue has the features of both ArrayBlockingQueue and DelayQueue. ArrayBlockingQueue is a bounded blocking queue where as DelayQueue is an unbounded blocking queue. LinkedBlockingQueue sits in the middle as it is an optionally-bounded blocking queue…
ConcurrentLinkedQueue in Java is an unbounded queue which is thread-safe. It stores its elements as linked nodes where each node stores a reference to the next node. ConcurrentLinkedQueue class implements Queue interface and is part of java.util.concurrent package. How ConcurrentLinkedQueue differs from the BlockingQueue implementations like ArrayBlockingQueue, PriorityBlockingQueue is that…
ArrayBlockingQueue is a bounded blocking queue which internally uses an array to store elements. This queue orders elements FIFO (first-in-first-out). The head of the queue is the element that has been on the queue the longest time. The tail of the queue is that element that has been on the…
PriorityBlockingQueue in Java is an implementation of BlockingQueue interface and is part of java.util.concurrent package. PriorityBlockingQueue is an unbounded queue PriorityBlockingQueue is logically unbounded, that’s how it differs from ArrayBlockingQueue which is a bounded queue and LinkedBlockingQueue which is optionally-bounded. PriorityBlockingQueue though unbounded is created with an initial capacity which…
Condition interface which resides in java.util.concurrent.locks has methods for inter thread communication similar to Object class monitor methods (wait, notify and notifyAll). Condition provides methods like await(), signal(), signalAll(). Where a Lock replaces the use of synchronized methods and statements, a Condition replaces the use of the Object monitor methods.…
java.util.concurrent.atomic package in Java has classes that support lock free atomic operations. That means using classes contained in this package atomicity of operations is guaranteed for integer, long, boolean values along with object references and arrays with out using explicit synchronization or locks. In this post we’ll discuss one of…
