HOME





Java ConcurrentMap
The Java programming language's Java Collections Framework version 1.5 and later defines and implements the original regular single-threaded Maps, and also new thread-safe Maps implementing the interface among other concurrent interfaces. In Java 1.6, the interface was added, extending , and the interface was added as a subinterface combination. Java Map Interfaces The version 1.8 Map interface diagram has the shape below. Sets can be considered sub-cases of corresponding Maps in which the values are always a particular constant which can be ignored, although the Set API uses corresponding but differently named methods. At the bottom is the java.util.concurrent.ConcurrentNavigableMap, which is a multiple-inheritance. * ** *** **** ***** *** **** Implementations ConcurrentHashMap For unordered access as defined in the java.util.Map interface, the java.util.concurrent.ConcurrentHashMap implements java.util.concurrent.ConcurrentMap. The mechanism is a hash access to ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Java Collections Framework
The Java collections framework is a set of classes and interfaces that implement commonly reusable collection data structures. Although referred to as a framework, it works in a manner of a library. The collections framework provides both interfaces that define various collections and classes that implement them. Differences from Arrays Collections and arrays are similar in that they both hold references to objects and they can be managed as a group. However, unlike arrays, collections do not need to be assigned a certain capacity when instantiated. Collections can also grow and shrink in size automatically when objects are added or removed. Collections cannot hold basic data type elements (primitive types) such as int, long, or double; instead, they hold Wrapper Classes such as Integer, Long, or Double. History Collection implementations in pre- JDK 1.2 versions of the Java platform included few data structure classes, but did not contain a collections framework. The standa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Skip List
In computer science, a skip list (or skiplist) is a probabilistic data structure that allows \mathcal(\log n) average complexity for search as well as \mathcal(\log n) average complexity for insertion within an ordered sequence of n elements. Thus it can get the best features of a sorted array (for searching) while maintaining a linked list-like structure that allows insertion, which is not possible with a static array. Fast search is made possible by maintaining a linked hierarchy of subsequences, with each successive subsequence skipping over fewer elements than the previous one (see the picture below on the right). Searching starts in the sparsest subsequence until two consecutive elements have been found, one smaller and one larger than or equal to the element searched for. Via the linked hierarchy, these two elements link to elements of the next sparsest subsequence, where searching is continued until finally searching in the full sequence. The elements that are skipped ov ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lock Convoy
In computer science, a lock convoy is a performance problem that can occur when using locks for concurrency control in a multithreaded application. A lock convoy occurs when multiple threads of equal priority contend repeatedly for the same lock. Unlike deadlock and livelock situations, the threads in a lock convoy do progress; however, each time a thread attempts to acquire the lock and fails, it relinquishes the remainder of its scheduling quantum and forces a context switch. The overhead of repeated context switches and underutilization of scheduling quanta degrade overall performance. Lock convoys often occur when concurrency control primitives such as locks serialize access to a commonly used resource, such as a memory heap Memory pools, also called fixed-size blocks allocation, is the use of pools for memory management that allows dynamic memory allocation comparable to malloc or C++'s operator new. As those implementations suffer from fragmentation because o ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lock Free
In computer science, an algorithm is called non-blocking if failure or suspension of any thread cannot cause failure or suspension of another thread; for some operations, these algorithms provide a useful alternative to traditional blocking implementations. A non-blocking algorithm is lock-free if there is guaranteed system-wide progress, and wait-free if there is also guaranteed per-thread progress. "Non-blocking" was used as a synonym for "lock-free" in the literature until the introduction of obstruction-freedom in 2003. The word "non-blocking" was traditionally used to describe telecommunications networks that could route a connection through a set of relays "without having to re-arrange existing calls" (see Clos network). Also, if the telephone exchange "is not defective, it can always make the connection" (see nonblocking minimal spanning switch). Motivation The traditional approach to multi-threaded programming is to use locks to synchronize access to shared resourc ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Java ConcurrentMap 1-thread Put Entries Vs Time Test Graph
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's most populous island, home to approximately 56% of the Indonesian population. Indonesia's capital city, Jakarta, is on Java's northwestern coast. Many of the best known events in Indonesian history took place on Java. It was the centre of powerful Hindu-Buddhist empires, the Islamic sultanates, and the core of the colonial Dutch East Indies. Java was also the center of the Indonesian struggle for independence during the 1930s and 1940s. Java dominates Indonesia politically, economically and culturally. Four of Indonesia's eight UNESCO world heritage sites are located in Java: Ujung Kulon National Park, Borobudur Temple, Prambanan Temple, and Sangiran Early Man Site. Formed by volcanic eruptions due to geologic subduction of the Australi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Java ConcurrentMap 8 Thread Put Entries Vs Time Performance Graph
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's most populous island, home to approximately 56% of the Indonesian population. Indonesia's capital city, Jakarta, is on Java's northwestern coast. Many of the best known events in Indonesian history took place on Java. It was the centre of powerful Hindu-Buddhist empires, the Islamic sultanates, and the core of the colonial Dutch East Indies. Java was also the center of the Indonesian struggle for independence during the 1930s and 1940s. Java dominates Indonesia politically, economically and culturally. Four of Indonesia's eight UNESCO world heritage sites are located in Java: Ujung Kulon National Park, Borobudur Temple, Prambanan Temple, and Sangiran Early Man Site. Formed by volcanic eruptions due to geologic subduction of the Aust ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lock-free
In computer science, an algorithm is called non-blocking if failure or suspension of any thread cannot cause failure or suspension of another thread; for some operations, these algorithms provide a useful alternative to traditional blocking implementations. A non-blocking algorithm is lock-free if there is guaranteed system-wide progress, and wait-free if there is also guaranteed per-thread progress. "Non-blocking" was used as a synonym for "lock-free" in the literature until the introduction of obstruction-freedom in 2003. The word "non-blocking" was traditionally used to describe telecommunications networks that could route a connection through a set of relays "without having to re-arrange existing calls" (see Clos network). Also, if the telephone exchange "is not defective, it can always make the connection" (see nonblocking minimal spanning switch). Motivation The traditional approach to multi-threaded programming is to use locks to synchronize access to shared resou ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Joshua Bloch
Joshua J. Bloch (born August 28, 1961) is an American software engineer and a technology author, formerly employed at Sun Microsystems and Google. He led the design and implementation of numerous Java platform features, including the Java Collections Framework, the package, and the mechanism."About the Author"
''Effective Java Programming Language Guide''
He is the author of the programming guide ''Effective Java'' (2001), which won the 2001 Jolt Award, and is a co-author of two other Java books, ''Java Puzzlers'' (2005) and ''Java Concurrency In Practice'' (2006). Bloch holds a B.S. in

picture info

J2SE 1
J, or j, is the tenth letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its usual name in English is ''jay'' (pronounced ), with a now-uncommon variant ''jy'' ."J", ''Oxford English Dictionary,'' 2nd edition (1989) When used in the International Phonetic Alphabet for the ''y'' sound, it may be called ''yod'' or ''jod'' (pronounced or ). History The letter ''J'' used to be used as the swash letter ''I'', used for the letter I at the end of Roman numerals when following another I, as in XXIIJ or xxiij instead of XXIII or xxiii for the Roman numeral twenty-three. A distinctive usage emerged in Middle High German. Gian Giorgio Trissino (1478–1550) was the first to explicitly distinguish I and J as representing separate sounds, in his ''Ɛpistola del Trissino de le lettere nuωvamente aggiunte ne la lingua italiana'' ("Trissino's epistle about the letters recently added in the I ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


JavaWorld
''InfoWorld'' (abbreviated IW) is an information technology media business. Founded in 1978, it began as a monthly magazine. In 2007, it transitioned to a web-only publication. Its parent company today is International Data Group, and its sister publications include ''Macworld'' and ''PC World''. InfoWorld is based in San Francisco, with contributors and supporting staff based across the United States. Since its founding, ''InfoWorld''s readership has largely consisted of IT and business professionals. ''InfoWorld'' focuses on how-to, analysis, and editorial content from a mixture of experienced technology journalists and working technology practitioners. The site averages 4.6 million monthly page views and 1.1 million monthly unique visitors. History The magazine was founded by Jim Warren in 1978 as ''The Intelligent Machines Journal'' (IMJ). It was sold to IDG in late 1979. On 18 February 1980, the magazine name was changed to ''InfoWorld''. In 1986, the Robert X. Cringely ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Doug Lea
Douglas S. Lea is a professor of computer science and current head of the computer science department at State University of New York at Oswego, where he specializes in concurrent programming and the design of concurrent data structures. He was on the Executive Committee of the Java Community Process and chaired JSR 166, which added concurrency utilities to the Java programming language (see Java concurrency). On October 22, 2010, Doug Lea notified the Java Community Process Executive Committee he would not stand for reelection. Lea was re-elected as an at-large member for the 2012 OpenJDK governing board. Publications He wrote ''Concurrent Programming in Java: Design Principles and Patterns'', one of the first books about the subject. It is currently in its second edition. He is also the author of dlmalloc, a widely used public-domain implementation of malloc. Awards In 2010, he won the senior Dahl-Nygaard Prize. In 2013, he became a Fellow of the Association for Computing M ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]