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Project Valhalla (Java Language)
Project Valhalla is an experimental OpenJDK project to develop major new language features for Java 10 and beyond. The project was announced in July 2014 and is an experimental effort by Oracle, led by engineer Brian Goetz. The project page offers an overview as well as links to technical drafts and early-access builds. Planned features Valhalla is incubating Java language features and enhancements in these areas: * Value Classes and Objects: highly-efficient objects without their own identity (reference value). * Null-restricted and Nullable types, and Null-restricted Objects: for example, using ? or ! after type declaration to say if null is allowed or not. * Enhanced Primitive Boxing: for example, to allow code such as List. * Reified Generics: retaining actual type at runtime. These features will require both syntax and VM-level changes. Project components The project is organized into several JEPs (JDK Enhancement Proposals): * JEP draft: Value Objects (Withdrawn) * JEP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OpenJDK
OpenJDK (Open Java Development Kit) is a free and open-source implementation of the Java Platform, Standard Edition (Java SE). It is the result of an effort Sun Microsystems began in 2006, four years before the company was acquired by Oracle Corporation. The implementation is licensed under the GNU General Public License 2 with a linking exception, preventing components that linked to the Java Class Library becoming subject to the terms of the GPL license. OpenJDK is the official reference implementation of Java SE since version 7, and is the most popular distribution of the JDK. History Sun's promise and initial release Sun announced in JavaOne 2006 that Java would become open-source software, and on October 25, 2006, at the Oracle OpenWorld conference, Jonathan Schwartz said that the company intended to announce the open-sourcing of the core Java Platform within 30 to 60 days. Sun released the Java HotSpot virtual machine and compiler as free software under the GNU Gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Java (programming Language)
Java is a High-level programming language, high-level, General-purpose programming language, general-purpose, Memory safety, memory-safe, object-oriented programming, object-oriented programming language. It is intended to let programmers ''write once, run anywhere'' (Write once, run anywhere, WORA), meaning that compiler, compiled Java code can run on all platforms that support Java without the need to recompile. Java applications are typically compiled to Java bytecode, bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. The syntax (programming languages), syntax of Java is similar to C (programming language), C and C++, but has fewer low-level programming language, low-level facilities than either of them. The Java runtime provides dynamic capabilities (such as Reflective programming, reflection and runtime code modification) that are typically not available in traditional compiled languages. Java gained popularity sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oracle Corporation
Oracle Corporation is an American Multinational corporation, multinational computer technology company headquartered in Austin, Texas. Co-founded in 1977 in Santa Clara, California, by Larry Ellison, who remains executive chairman, Oracle was the List of the largest software companies, third-largest software company in the world in 2020 by revenue and market capitalization. The company's 2023 ranking in the Forbes Global 2000, ''Forbes'' Global 2000 was 80. The company sells Database, database software, particularly Oracle Database, and cloud computing. Oracle's core application software is a suite of enterprise software products, such as enterprise resource planning (ERP) software, human capital management (HCM) software, customer relationship management (CRM) software, enterprise performance management (EPM) software, Customer Experience Commerce (CX Commerce) and supply chain management (SCM) software. History Larry Ellison, Bob Miner, and Ed Oates co-founded Oracle in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brian Goetz
Brian (sometimes spelled Bryan in English) is a male given name of Irish and Breton origin, as well as a surname of Occitan origin. It is common in the English-speaking world. It is possible that the name is derived from an Old Celtic word meaning "high" or "noble". For example, the element ''bre'' means "hill"; which could be transferred to mean "eminence" or "exalted one". The name is quite popular in Ireland, on account of Brian Boru, a 10th-century High King of Ireland. The name was also quite popular in East Anglia during the Middle Ages. This is because the name was introduced to England by Bretons following the Norman Conquest. Bretons also settled in Ireland along with the Normans in the 12th century, and 'their' name was mingled with the 'Irish' version. Also, in the north-west of England, the 'Irish' name was introduced by Scandinavian settlers from Ireland. Within the Gaelic-speaking areas of Scotland, the name was at first only used by professional families of Iris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Value Type
In certain computer programming languages, data types are classified as either value types or reference types, where reference types are always implicitly accessed via references, whereas value type variables directly contain the values themselves. Properties of value types and reference types Even among languages that have this distinction, the exact properties of value and reference types vary from language to language, but typical properties include: * Primitive data types, such as Booleans, fixed-size integers, floating-point values, and characters, are value types. * Objects, in the sense of object-oriented programming, belong to reference types. * Assigning to a variable of reference type simply copies the reference, whereas assigning to a variable of value type copies the value. This applies to all kinds of variables, including local variables, fields of objects, and array elements. Likewise when calling a function: parameters of reference type are copies of the reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nullable Type
Nullable types are a feature of some programming languages which allow a value to be set to the special value NULL instead of the usual possible values of the data type. In statically typed languages, a nullable type is an option type, while in dynamically typed languages (where values have types, but variables do not), equivalent behavior is provided by having a single null value. NULL is frequently used to represent a missing value or invalid value, such as from a function that failed to return or a missing field in a database, as in NULL in SQL. In other words, NULL is undefined. Primitive types such as integers and Booleans cannot generally be null, but the corresponding nullable types (nullable integer and nullable Boolean, respectively) can also assume the NULL value. This can be represented in ternary logic as FALSE, NULL, TRUE as in three-valued logic. Example An integer variable may represent integers, but 0 (zero) is a special case because 0 in many programming ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boxing (computer Programming)
In computer science, boxing (a.k.a. wrapping) is the transformation of placing a primitive type within an object so that the value can be used as a reference. Unboxing is the reverse transformation of extracting the primitive value from its wrapper object. Autoboxing is the term for automatically applying boxing and/or unboxing transformations as needed. Boxing Boxing's most prominent use is in Java where there is a distinction between reference and value types for reasons such as runtime efficiency and syntax and semantic issues. In Java, a can only store values of type . One might desire to have a of , but this is not directly possible. Instead Java defines primitive wrapper classes corresponding to each primitive type: and , and , and , etc. One can then define a using the boxed type and insert values into the list by boxing them as objects. (Using generic parameterized types introduced in J2SE 5.0, this type is represented as .) On the other hand, C# has no primi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparison Of C Sharp And Java
This article compares two programming languages: C# with Java. While the focus of this article is mainly the languages and their features, such a comparison will necessarily also consider some features of platforms and libraries. C# and Java are similar languages that are typed statically, strongly, and manifestly. Both are object-oriented, and designed with semi- interpretation or runtime just-in-time compilation, and both are curly brace languages, like C and C++. Types Unified type system Both languages are statically typed with class-based object orientation. In Java the primitive types are special in that they are not object-oriented and they could not have been defined using the language itself. They also do not share a common ancestor with reference types. The Java reference types all derive from a common root type. C# has a unified type system in which all types (besides unsafe pointers) ultimately derive from a common root type. Consequently, all types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generics In Java
Generics are a facility of generic programming that were added to the Java programming language in 2004 within version J2SE 5.0. They were designed to extend Java's type system to allow "a type or method to operate on objects of various types while providing compile-time type safety". The aspect '' compile-time type safety'' required that parametrically polymorphic functions are not implemented in the Java virtual machine, since type safety is impossible in this case. The Java collections framework supports generics to specify the type of objects stored in a collection instance. In 1998, Gilad Bracha, Martin Odersky, David Stoutamire and Philip Wadler created Generic Java, an extension to the Java language to support generic types. Generic Java was incorporated in Java with the addition of wildcards. Hierarchy and classification According to ''Java Language Specification'': *A type variable is an unqualified identifier. Type variables are introduced by generic class declarati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generic Programming
Generic programming is a style of computer programming in which algorithms are written in terms of data types ''to-be-specified-later'' that are then ''instantiated'' when needed for specific types provided as parameters. This approach, pioneered in the programming language ML in 1973, permits writing common functions or data types that differ only in the set of types on which they operate when used, thus reducing duplicate code. Generic programming was introduced to the mainstream with Ada in 1977. With templates in C++, generic programming became part of the repertoire of professional library design. The techniques were further improved and ''parameterized types'' were introduced in the influential 1994 book '' Design Patterns''. New techniques were introduced by Andrei Alexandrescu in his 2001 book '' Modern C++ Design: Generic Programming and Design Patterns Applied''. Subsequently, D implemented the same ideas. Such software entities are known as ''generics'' in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
