100 likes | 396 Views
If You want to get excel in every aspect of programming language like java, C#, asp, php, just visit www.myassignmenthelp.net we will provide you the best online tutoring experience.
E N D
Introduction To JAVA www.myassignmenthelp.net
Overview of JAVA • Java is: • Platform independent programming language • Similar to C++ in syntax • Similar to Smalltalk in mental paradigm • Pros: also ubiquitous to net • Cons: interpreted, and still under development (moving target) www.myassignmenthelp.net
How it works…! Java is independent only for one reason: Only depends on the Java Virtual Machine (JVM), code is compiled to bytecode, which is interpreted by the resident JVM, JIT (just in time) compilers attempt to increase speed www.myassignmenthelp.net
Java Features • Well defined primitive data types: int, float, double, char, etc. • int 4 bytes [–2,147,648, 2,147,483,647] • Control statements similar to C++: if-then-else, switch, while, for • Interfaces • Exceptions • Concurrency • Packages • Name spaces • Reflection • Applet model • Automatic type checking and garbage collection • Simplifies pointers; no directly accessible pointer to memory, • Simplified network access, • Multi-threading www.myassignmenthelp.net
Applets, Servlets and Applications • Applets: • Applet is designed to be embedded in a Web page, and run by a browser • Applets run in a sandbox with numerous restrictions; for example, they can’t read files and then use the network • Servlet: • A servlet is designed to be run by a web server • Application: • An application is a conventional program www.myassignmenthelp.net
The Java programming environment • Java programming language specification • Syntax of Java programs • Defines different constructs and their semantics • Java byte code: Intermediate representation for Java programs • Java compiler: Transform Java programs into Java byte code • Java interpreter: Read programs written in Java byte code and execute them • Java virtual machine: Runtime system that provides various services to running programs • Java programming environment: Set of libraries that provide services such as GUI, data structures,etc. • Java enabled browsers: Browsers that include a JVM + ability to load programs from remote hosts www.myassignmenthelp.net
Java - Security • Pointer denial - reduces chances of virulent programs corrupting host, • Applets even more restricted - • May not • run local executables, • Read or write to local file system, • Communicate with any server other than the originating server. www.myassignmenthelp.net
Object-Oriented • Java supports OOD • Polymorphism • Inheritance • Encapsulation • Java programs contain nothing but definitions and instantiations of classes • Everything is encapsulated in a class! www.myassignmenthelp.net
Java Advantages • Portable - Write Once, Run Anywhere • Security has been well thought through • Robust memory management • Designed for network programming • Multi-threaded (multiple simultaneous tasks) • Dynamic & extensible (loads of libraries) • Classes stored in separate files • Loaded only when needed www.myassignmenthelp.net
Thank You www.myassignmenthelp.net