Introduction to Java
Java is an object oriented and structured programming language, designed by Sun Microsystems in the year 1991. Java is a third generation programming language. It has an in built application interface which has the ability to handle the graphics and user interfaces that creates the applets or applications.The very advantage of java is its “portability”, the programmer can write the program and compile in the same kind of environment as it is written and after that it can be run anywhere.
Java relates to both C and C++, it uses the syntax of C and the object oriented concepts from c++ and this makes Java appealing. When a source code is given as the input, the output from java compiler is the “bytecode”. Bytecode contains set of instructions which will be executed by Java Virtual machine (JVM). In a more simple way, I can say JVM interprets the bytecode and this is the reason that java can be run anywhere. Applets are the programs which are embedded in to web page and can be executed where as the applications are directly executed by JVM.
It is not always possible to compile the complete program at the same time, so java uses just-in-time compiler to compile a set of bytecodes in real time for execution and the remaining codes will just be interpreted and thus makes the execution of Java program faster. The two main building blocks of java programming are the classes and objects. Objects are the instance of class and class is a template for creating objects.
Unlike in c/c++ you need not manually allocate/de allocate dynamic memory, java itself does this and also it has garbage collection for the unused objects. Java program handles the run time errors too. Java supports multithreaded programming.
Java Programming Language : What it is ?
A high-level programming language developed by Sun Microsystems. Java was originally called OAK, and was designed for handheld devices and set-top boxes. Oak was unsuccessful so in 1995 Sun changed the name to Java and modified the language to take advantage of the burgeoning World Wide Web.Java is an object-oriented language similar to C++, but simplified to eliminate language features that cause common programming errors. Java source code files (files with a .java extension) are compiled into a format called bytecode (files with a .class extension), which can then be executed by a Java interpreter. Compiled Java code can run on most computers because Java interpreters and runtime environments, known as Java Virtual Machines (VMs), exist for most operating systems, including UNIX, the Macintosh OS, and Windows. Bytecode can also be converted directly into machine language instructions by a just-in-time compiler (JIT).
Java is a general purpose programming language with a number of features that make the language well suited for use on the World Wide Web. Small Java applications are called Java applets and can be downloaded from a Web server and run on your computer by a Java-compatible Web browser, such as Netscape Navigator or Microsoft Internet Explorer.
Java Programmers : Why They Are Highly In Demand
Java is a complex object-oriented computer programming language which is a result of some concepts taken from other computer languages such as C and C++. Although there are abound negative feedbacks, Java is generally considered to be the most admired multi-facets computing language that is utilized in today’s generation.There are quite a number of reasons why Java is on the top spot when it comes to computer language. First off is the fact that composite dynamic website processes are achievable in Java programming. With Java being a multithreaded language, its use in superb and fast applications is increasing. An evidence of this is its presence in most gadget applications up to the fastest computers found today. As Java applets are platform-independent, the program can straightforwardly be accessed by a software developer and it can be run in various platforms. One of Java’s best features is the truth that even it is a very powerful and vigorous, this programming languages comes out free. It is an open source programming language which has a mechanical garbage collection. With regards to the database, Java can adapt to any database may it be paid or free. And the last but not the least is the reality that Java language is a collection of well planned and APIs which aids Java coders to do improved outputs without any annoyance.
The IT world has a number of platforms nowadays. This gift of numerous choices provides advantage and disadvantages. On one hand it provide more options to the developers or consumers; on the other hand making a software that is working on all platforms is becoming very scarce. To address this concern, there is now Java Platform which is intended for running extremely interactive, lively, and safe applets and computer applications on a set of connections of different computers.
Software developers can make applications on a single platform to deliver to that same platform — the Java Platform, which is accessible on a wide array of operating systems. This greatly minimizes the developing cost of the software. For support workforce, version management and advancement are much easier for the reason that Java-enabled software application can be found in a central storage area and work from that location for each individual handling.
The bottom line is, if you wish to study Java and become a professional on this field, you will certainly be ahead of the game. To start off, since Java is a popular language, you can turn on to basic Java tutorials found online or find a Java book with positive reviews. Deciding to be in this field is an action you shall never regret.
Java Application Programming
Java Application Programming was developed by a person named James Gosling in 1995, at a present date subsidiary of Oracle Corporations, which was then called as sun Micro-systems. JVM or Java Virtual Machines are needed to run these java applications which are compiled to class file format. Irrespective of the computer architecture JVM is always required to run this type of files. Java Application Programming is specifically designed to have the least amount of implementation bottlenecks. It works on the principle of “write once, run anywhere” pattern.
It means once your write the coding of the program, you can use it on other destination too. You don’t need to write it again and gain every time. Java is not only a programming language but also a software platform, which lets the application developers to use this simpler, class based and object-oriented programming language instead of the complicated high level languages like C and C++.
But the major disadvantage of using Java Application Programming is that, the programs written in Java are slower and need more memory space to get stored then the programs written in C language.
For that concern, the sun Micro-systems have been working upon java technologies under the specifications of the Java community process. And have achieved remarkable success in the context of introducing Just in time compilation model to run these applications in the year 1997-98. Some new language features have been added to the language like inner classes, optional assertions and String-buffer class etc.
Java has compilers in it, which conduct the basic functions whenever an application developer writes a code with syn-taxes and characters to run a particular Java Application Programming code.
For faster speed a company names Systronix has developed a micro-controller called jStik based on a line of java processors. A standard edition for Java Application Programming language has various components. It uses multi-tier architecture for database connectivity. It uses XMl files to store data and writing codes. JDOM is used for outputting XML data from Java code.
All the components of java work together to perform a given task, and such components are listed below:
1. Development tools and APIs as Java complier, Java debugger, Javadoc and JPDA
2. Deployment technologies could have sub-parts like Java web-start and Java plug-in
3. User interface tool kits are swing, AWT, sound, input methods, java 2D and accessibility.
4. Integration APIs are RMI, JDBC, JNDI, and CORBA.
5. Core APIs are like XML, logging, beans, Locale support, Preferences, Collections, JNI, Security, Lang, Util, New I/O and Networking
6. Java virtual machines are of three types as, Java hotspot client compiler, Java hotspot server complier ad Java hotspot VM runtime.
The various Java platforms are:
• Solaris
• Linux
• Windows
• And others.
