Java Chapter 1

Q. Explain the best way how to set java path?

Ans:-  Just go to Start-Run-Cmd

Your Command Prompt will open.

copy path of your "javac.exe " simply at location --> C:\Program Files\Java\jdk1.8.0_25\bin
and type command in dos prompt

set path="C:\Program Files\Java\jdk1.8.0_25\bin"
e.g.

This is one of the simple way for beginners to set the java path(Most of freshers face trouble to set java path).

Q. Explain the Types of Java Applications.

Ans:- In Java we can build following types of applications:

Desktop/Standalone Application

In Java we can build the desktop applications or windows based applications, which are installed on single or stand along computer such as Media Player, Calculator, Antivirus etc using Swing and AWT.

Web Application

In Java using servlet, jsp, structs, jsf etc. we can build the server side application and dynamic web pages.

Enterprise/Distributed Application

Using EJB in Java we can build the application which are distributed in nature such as railway, airlines, banking application etc. In these application we need high level security, load balancing clustering etc.

Mobile Application

To build the Mobile application we use the Android and Java ME of Java

Q. Explain the Features of Java

Ans: - 

Features of Java is explain below:

Simple

According to Sun Microsystems Java language is simple language because of following factors:-

Syntax of Java is based on C++ , so who knows about C++ it is easy to learn.

Removed many confusing and/or rarely-used features e.g., explicit pointers, operator overloading etc.

Java has the automatically Garbage Collection So there is no need to remove unreferenced objects.

Object-oriented

Java is a Object Oriented language means we organize our software as a combination of different types of objects that incorporates both data and behavior. OOPs is a methodology that simplify the software development and maintenance by providing some advance features.

Basic concepts of OOPs are:

1.    Object 2.    Class 3.    Inheritance 4.    Polymorphism 5.    Abstraction 6.    Encapsulation

Platform Independent

Java is a platform independent language. A platform is the hardware or software environment in which a program runs. There are two types of platforms software-based and hardware-based. Java provides software-based platform. Platform of  Java differs from most other platforms in the sense that it's a software-based platform that runs on top of other hardware-based platforms. Java Platform has two components: 1.    Runtime Environment 2.    API(Application Programming Interface)

Java language code can be run on multiple platforms e.g.Windows, Linux, Sun Solaris, Mac/OS etc. We just have to install JVM on Operating System where we want to execute Java Program. Java language code is compiled by the compiler and converted into bytecode. This bytecode is a platform independent code because it can be run on multiple platforms i.e. Write Once and Run Anywhere(WORA). So we found that Java is a Platform Independent Language.

Secured

Java is secured Language because there is no explicit pointer and the programs of Java run inside Virtual machine (JVM) sandbox. Developers can also increase the security by using SSL, JAAs and cryptography etc.

Architecture-neutral

In Java there is no implementation dependent features for e.g. size of primitive types is set. Multi-threaded In Java we can build the multi threaded applications. A thread is a mini process or like a separate program, executing concurrently. We can write Java programs that deal with many tasks at a time. There are many advantages of multi-threading for e.g. Multi Threaded applications can shares the same memory and resources. Threads are important for multi-media, Web applications, Games etc.

Portable

Java is Portable language because we can move the Java byte Code from one machine or platform to another machine or platform.

High-performance

Java is a High performance language then C, C++ etc. because of Byte Code and other features.

Distributed

In Java we can build distributed applications which can run on multiple machine simultaneously.  RMI and EJB are used for creating distributed applications. In Java we may access files and other resources by calling the methods from any machine connected to network or internet.

Robust 

Java is Robust in nature, Robust means strong and Java uses strong memory management strategy. Because there is no pointers, automatic garbage collection, exception handling, type check mechanism etc are the features of Java which make it Robust.