Features of Java:

Sun Microsystems formally elaborates Java with the given features:

• Compiled and interpreted
• Platform-Independent and Portable
• Object-Oriented
• Robust and Secure
• Distributed
• Familiar, Simple and Small
• Multithreaded and Interactive
• High Performance
• Dynamic and Extensible

The mentioned characteristics made Java the first application language of all over the World.

Compiled and interpreted

Generally any language uses either compiler or interpreter to execute a program. But Java has compiler and interpreter both. Then, it is called as a two stage system.  Java compiler first translates its source program into its byte code instructions. A Byte codes are not a machine instructions and thus, in the 2^nd stage, Java interpreter produces machine code which can be directly executed through the machine.  We could thus say that Java is compiled and interpreted.

Platform-Independent and Portable

Java programs can be simply moved from one computer to another, anytime and anywhere. Modifications and upgrades in OS the processors and system resources will not force any modification in Java programs.  This is the reason in which Java has become popular in Internet. You could download a Java applet from a remote computer onto our local system through internet and execute it locally.

Java makes sure portability in two ways. First one is, Java compiler produces bytecode instruction which can be implemented on any machine.      And the Second one is, the size of the primitive data types is machine independent.

Object-Oriented

Java is truly object-oriented language.  In the Java Almost everything is an object.  All the data and program codes reside inside the classes and objects.  It comes within an extensive set of classes, arranged in packages which we could use in our programs through inheritance.

Robust and Secure

It is a robust language.  Java has strict compile time and run time checking for data types. Java is designed as a garbage-collected language relieving the programmers virtually all memory management problems. It also incorporates the concept of exception handling that captures series errors and eliminates any risk of crashing the system.

A Security becomes an important issue for a language which is used for programming for internet.  Java systems not only verify memory access but also ensure that no viruses are communicated within an applet. The absence of pointers in Java ensures in which programs cannot gain access to memory locations without proper authorization.

Distributed

Java is designed as a distributed language for making applications on networks. It has the ability to share data and programs both.   There applications can open and access remote objects on Internet as simply as they can do in a local system. This enables various programmers at multiple remote locations to collaborate and work together on a single project.

Simple, Small and Familiar

Java is a small and easy language. It does not use pointers, preprocessor header files, goto statements and several others. Java also eliminates operator overloading and multiple inheritance.  It uses several constructs of C and C++ and thus, Java code "just like a C++" code.

Multithreaded and Interactive

In Java Multithreaded means handling multiple or several tasks concurrently. It supports multithreaded programs. This means in which we require not wait for the application to finish one task before starting another. For instance, we can see any motion picture and at the similar time we can download any picture from remote computer. This characteristic greatly improves the interactive performance of graphical applications.

High performance

It performance is impressive for an interpreted language, mostly due to the use of intermediate byte code. Java architecture is also designed to decrease overheads in during runtime. In additions, the incorporation of multithreading enhances the whole execution speed of Java program.

Dynamic and Extensible

Java is a dynamic language. It is capable of dynamically connecting in new class libraries, object and methods.  It could also determine the type of class by a query, making it possible to either dynamically connect or abort the program, depending on the response.

Functions written in C or C++ can be used in Java. These techniques are called as native methods. This facility enables the programmers to use the efficient functions available in these languages. Native techniques are connects dynamically at run time.