Java (programming language) - Wikipedia, the free encyclopedia. For the natural language from the Indonesian island of Java, see Javanese language. This article is about a programming language. For the software package downloaded from java. Java SE. Java. Paradigm. Multi- paradigm: Object- oriented (class- based), structured, imperative, generic, reflective, concurrent. Designed by. James Gosling. Developer. Sun Microsystems (now owned by Oracle Corporation)First appeared. May 2. 3, 1. 99. 5; 2. It is intended to let application developers . As of 2. 01. 6, Java is one of the most popular programming languages in use. The language derives much of its syntax from C and C++, but it has fewer low- level facilities than either of them. The original and reference implementation Java compilers, virtual machines, and class libraries were originally released by Sun under proprietary licences. As of May 2. 00. 7, in compliance with the specifications of the Java Community Process, Sun relicensed most of its Java technologies under the GNU General Public License. Others have also developed alternative implementations of these Sun technologies, such as the GNU Compiler for Java (bytecode compiler), GNU Classpath (standard libraries), and Iced. Tea- Web (browser plugin for applets). The latest version is Java 8, which is the only version currently supported for free by Oracle, although earlier versions are supported both by Oracle and other companies on a commercial basis. History. James Gosling, Mike Sheridan, and Patrick Naughton initiated the Java language project in June 1. Later the project went by the name Green and was finally renamed Java, from Java coffee. Fairly secure and featuring configurable security, it allowed network- and file- access restrictions. Programs written in Java have a reputation for being slower and requiring more memory than those written in C++. However, Java programs' execution speed improved. The Most Important Things in Life Aren't Things. Life with Heidi includes travel, entertainment, easy recipes with some giveaways. Welcome to the home of Oracle Solaris open source projects on java.net! This project will be a hub to provide developer information and resources for the open source. Download Link for Head First Java Ebook. The following Head First Java Ebook is of better quality than the scanned one. It’s not split into several PDFs of. Trading in Binary Options or other off-exchange products carries a high level of risk and may not be suitable for everyone. Before trading, you are strongly advised. Major web browsers soon incorporated the ability to run Java applets within web pages, and Java quickly became popular, while mostly outside of browsers, that wasn't the original plan. In January 2. 01. Oracle announced that Java runtime environments based on JDK 9 will discontinue the browser plugin. J2. EE included technologies and APIs for enterprise applications typically run in server environments, while J2. ME featured APIs optimized for mobile applications. The desktop version was renamed J2. SE. In 2. 00. 6, for marketing purposes, Sun renamed new J2 versions as Java EE, Java ME, and Java SE, respectively. In 1. 99. 7, Sun Microsystems approached the ISO/IEC JTC 1 standards body and later the Ecma International to formalize Java, but it soon withdrew from the process. Sun generated revenue from Java through the selling of licenses for specialized products such as the Java Enterprise System. On November 1. 3, 2. Sun released much of its Java virtual machine (JVM) as free and open- source software, (FOSS), under the terms of the GNU General Public License (GPL). On May 8, 2. 00. 7, Sun finished the process, making all of its JVM's core code available under free software/open- source distribution terms, aside from a small portion of code to which Sun did not hold the copyright. Java software runs on everything from laptops to data centers, game consoles to scientific supercomputers. Major release versions of Java, along with their release dates: JDK 1. January 2. 1, 1. 99. JDK 1. 1 (February 1. J2. SE 1. 2 (December 8, 1. J2. SE 1. 3 (May 8, 2. J2. SE 1. 4 (February 6, 2. J2. SE 5. 0 (September 3. Java SE 6 (December 1. Java SE 7 (July 2. Java SE 8 (March 1. Practices. Java platform. Java Control Panel, version 7. One design goal of Java is portability, which means that programs written for the Java platform must run similarly on any combination of hardware and operating system with adequate runtime support. This is achieved by compiling the Java language code to an intermediate representation called Java bytecode, instead of directly to architecture- specific machine code. Java bytecode instructions are analogous to machine code, but they are intended to be executed by a virtual machine (VM) written specifically for the host hardware. End users commonly use a Java Runtime Environment (JRE) installed on their own machine for standalone Java applications, or in a web browser for Java applets. Standard libraries provide a generic way to access host- specific features such as graphics, threading, and networking. The use of universal bytecode makes porting simple. However, the overhead of interpreting bytecode into machine instructions makes interpreted programs almost always run more slowly than native executables. However, just- in- time (JIT) compilers that compile bytecodes to machine code during runtime were introduced from an early stage. Java itself is platform- independent, and is adapted to the particular platform it is to run on by a Java virtual machine for it, which translates the Java bytecode into the platform's machine language. This implementation is based on the original implementation of Java by Sun. The Oracle implementation is available for Microsoft Windows (still works for XP, while only later versions currently . Because Java lacks any formal standardization recognized by Ecma International, ISO/IEC, ANSI, or other third- party standards organization, the Oracle implementation is the de facto standard. The Oracle implementation is packaged into two different distributions: The Java Runtime Environment (JRE) which contains the parts of the Java SE platform required to run Java programs and is intended for end users, and the Java Development Kit (JDK), which is intended for software developers and includes development tools such as the Java compiler, Javadoc, Jar, and a debugger. Open. JDK is another notable Java SE implementation that is licensed under the GNU GPL. The implementation started when Sun began releasing the Java source code under the GPL. As of Java SE 7, Open. JDK is the official Java reference implementation. The goal of Java is to make all implementations of Java compatible. Historically, Sun's trademark license for usage of the Java brand insists that all implementations be . This resulted in a legal dispute with Microsoft after Sun claimed that the Microsoft implementation did not support RMI or JNI and had added platform- specific features of their own. Sun sued in 1. 99. US$2. 0 million, as well as a court order enforcing the terms of the license from Sun. This environment enables portable server- side applications. Performance. Programs written in Java have a reputation for being slower and requiring more memory than those written in C++. With Java 1. 5, the performance was improved with the addition of the java. Lock free implementations of the Concurrent. Maps and other multi- core collections, and it was improved further Java 1. Some platforms offer direct hardware support for Java; there are microcontrollers that can run Java in hardware instead of a software Java virtual machine, and ARM based processors can have hardware support for executing Java bytecode through their Jazelle option (while its support is mostly dropped in current implementations of ARM). Automatic memory management. Java uses an automatic garbage collector to manage memory in the object lifecycle. The programmer determines when objects are created, and the Java runtime is responsible for recovering the memory once objects are no longer in use. Once no references to an object remain, the unreachable memory becomes eligible to be freed automatically by the garbage collector. Something similar to a memory leak may still occur if a programmer's code holds a reference to an object that is no longer needed, typically when objects that are no longer needed are stored in containers that are still in use. If methods for a nonexistent object are called, a . In some languages, memory for the creation of objects is implicitly allocated on the stack, or explicitly allocated and deallocated from the heap. In the latter case the responsibility of managing memory resides with the programmer. If the program does not deallocate an object, a memory leak occurs. If the program attempts to access or deallocate memory that has already been deallocated, the result is undefined and difficult to predict, and the program is likely to become unstable and/or crash. This can be partially remedied by the use of smart pointers, but these add overhead and complexity. Note that garbage collection does not prevent . Ideally, it will occur when a program is idle. It is guaranteed to be triggered if there is insufficient free memory on the heap to allocate a new object; this can cause a program to stall momentarily. Explicit memory management is not possible in Java. Java does not support C/C++ style pointer arithmetic, where object addresses and unsigned integers (usually long integers) can be used interchangeably. This allows the garbage collector to relocate referenced objects and ensures type safety and security. As in C++ and some other object- oriented languages, variables of Java's primitive data types are either stored directly in fields (for objects) or on the stack (for methods) rather than on the heap, as is commonly true for non- primitive data types (but see escape analysis). This was a conscious decision by Java's designers for performance reasons. Java contains multiple types of garbage collectors. However, there are also several other garbage collectors that can be used to manage the heap. For 9. 0% of applications in Java, the Concurrent Mark- Sweep (CMS) garbage collector is sufficient. Unlike C++, which combines the syntax for structured, generic, and object- oriented programming, Java was built almost exclusively as an object- oriented language. Java reuses some popular aspects of C++ (such as printf() method). Unlike C++, Java does not support operator overloading. There are three different styles of comments: a single line style marked with two slashes (//), a multiple line style opened with /* and closed with */, and the Javadoc commenting style opened with /** and closed with */. Oracle Solaris Open Source Projects on java. This project will be a hub to provide developer information and resources for the open source projects. Oracle Solaris operating system. Here you will find access to the source. Oracle has made to the many 3rd party free and open source components. Apache web server, Python and Perl run time environments, and many other GNU command. Some of these modules have been licensed under the Common Development and Distribution License (CDDL). This isolation prevents processes. X provides the layer between the hardware devices and. GNOME and KDE. Lib. Micro was developed by Bart Smaalders and. Phil Harman as part of their If Linux is faster it's a Solaris bug performance campaign. Lib. Micro is Open. Source and uses the CDDL license.
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