A Brief Intro to Java for C/C++ Programmers
             -------------------------------------------
		      T.A. Gonsalves, IIT Mandi

A list of features of Java, for programmers familiar with C.

Compared to C++, Java is:
* Strictly object-oriented -- all code must be in a Class

* Supports only single inheritance, Class Object is the base of the
  class hierarchy.  However, a Java class can also implement one or
  more interfaces to provide a form of multiple inheritance.  An
  interface is similar to a pure virtual class in C++.

Compared to C and C++: 

* Java source is compiled to machine-independent bytecodes (.class
  file).  The .class files are platform independent.  Bytecodes are
  interpreted by a Java Virtual Machine (JVM) that is
  platform-specific.  

* The Java standard includes a very rich set of classes:  basic data
  structures (collections), networking, GUI, database access,
  multi-threading, thread-safe concurrent data structures, atomic
  variables, etc.  These are guaranteed to be available on all
  conformant implementations.

* Multi-threading is supported by user-level threads in the JVM on
  platforms that do not provide kernel threads.

* Thus, Java is "write once, run anywhere", unlike C/C++ which have to
  be compiled for each target platform.  The standard libraries in
  C/C++ are relatively small, rich sets of optional libraries are
  available but these may not be installed on all platforms of
  interest.

* Java is inherently slower than a C/C++ program that is compiled to
  machine code by an optimising compiler.  However, the Hotspot JVM
  does on-the-fly compilation of frequently used bytecode segments to
  machine code to achieve nearly C-like performance.

* Java provides dynamic memory management via a "garbage collector".
  The programmer does not have to (indeed, cannot) free an object that is
  no longer needed.  The garbage collector does this automatically.

* Java supports dynamic loading of classes into a running program.
  The loaded classes could be sourced from any machine in the
  Internet.

There are 3 commonly-used Java standards:
* Java Standard Edition (Java SE) -- used on most computers

* Java Enterprise Edition (Java EE) -- used for building large
  enterprise-class applications

* Java Micro Edition (Java ME) -- used for small mobile platforms

[Version 1, 1/4/2015]