report on core java for two months institutional training

the following report is submitted by me on 2months training:-

name= Daljeet singh pathania

class= pre-final year

branch=Information Technology

topic=core java

college= Guru Nanak Dev Engineering College, ludhiana(p.b)

DOEACC CENTERSRINAGAR/JAMMU

(FORMERLY CEDTI SRINAGAR/JAMMU)

DOEACC is an autonomous body of department of Information Technology, Ministry of Communication & Information Technology, Govt. of India.

DOEACC institute was established in 1983. There are 23 DOEACC institute in all over India. It is one of the most prestigious institutes in India, which offers various computer language courses, certification course, hardware courses and many more in the field of computers.

HISTORY OF JAVA

Java was conceived by james gosling, Patrick Naughton, Chris Warth, Ed Frank and Mike Sheridan at Sun Microsystems, Inc. in 1991.It took 18 months to develop the first working version. This language was initially called “OAK,” but was renamed “java” in 1995.The original impetus for java was not the Internet! Instead, the primary motivation was the need for a platform independent language that could be used to create software to be embedded in various consumer electronic devices.thi s effort ultimately led to creation of java. The emergence of the World Wide Web, java was propelled to the forefront of the computer language design, because the Web too demanded portable programs.

INTRODUCTION TO JAVA

To fully understand java, one must understand the reasons behind its creation, the forces that shaped it, and legacy that it inherits. Like the successful computer language that came before, java is blend of the best elements of its rich heritage combined with the innovative concepts required by its unique mission. Much of the character of the java is inherited from C and C++.From C, java derives its syntax. Many of java’s OOPs features were influenced by C++. Creation of java was deeply rooted in the process of refinement and adaptation that has been occurring in computer programming language for the past several decades.

FEATURES OF JAVA

JAVA APPLETS

An applet is a special kind of java program that is designed to be transmitted over the Internet and automatically executed by a java-compatible web browser. Furthermore, an applet is downloaded on the demand, without further interaction with user. If the user click a link that contain the applet, the applet will automatically downloaded and run in the browser. The creation of the applet changed Internet programming because it expanded the universe of objects that can move about freely in the cyberspace.

Java’s Magic: The Bytecode

The output of the java compiler is not the executable code Rather, it is bytecode. Bytecode is a highly optimized set of instructions designed to be executed by the java run time system, which is called the Java Virtual Machine(JVM). Translating a java program into the bytecode makes it much easier to run a program in a wide variety of environments because only the JVM needs to be implemented for each platform. Although the details of the JVM will differ from platform to platform, all understand the same bytecode.

Servlets: java on the server side

A servlet is a small program that executes on the server. A servlet is a small program that executes on the server. Just as applets dynamically extend the functionality of a web browsers, servlets dynamically extend the functionality of a web server. Thus, with the advent of the servlet, Java spanned both sides of the client/server connection. Servlent are used to create dynamically generated content that is then served to the client. The servlent offers several advantages, including increased performance. Because servlents(like all Java programs) are compiled into bytecode and executed by the JVM, they are highly portable.

Instead of above main features there are several other important features are as following:-

· Simple

· Secure

· Portable

· Object-oriented

· Robust

· Multithreaded

· Architecture-neutral

· Interpreted

· High performance

· Distributed

· Dynamic

The Evolution of java

The initial release of java was nothing short of revolutionary, but it did not mark the end of java’s era of rapid innovation. The java 1.0 was the first release of java. Soon after the release of Java 1.0, the designers of Java had already created Java 1.1.The next major release of Java was Java 2. Where the “2”indicates “second generation.” The creation of Java 2 was watershed event, marking the beginning of Java’s “modern age.” The first release of Java 2 carried the version number 1.2.

Java 2 added support for a number of new features, such as Swing and the Collections Framework, and it enhanced the Java Virtual Machine and various programming tools.

J2SE 1.3 was the first major upgrade to the original Java 2 release. For the most part, it added to existing functionality and “tightened up” the development environment.

The release of J2SE 1.4 further enhanced Java. The release contained several important upgrades, enhancements, and additions. For example, it added the new keyword assert.

The next release of Java was J2SE 5, and it was revolutionary. J2SE 5 fundamentally expanded the scope, power and range of language.

· Generics

· Annotations

· Autoboxing and auto-unboxing

· Enumerations

· Enhanced, for-each style for loop

· Variable-length arguments (varargs)

· Static import

· Formatted I/O

· Concurrency utilities

JAVA SE 6

The newest release of Java is called Java SE 6. With the release of Java SE 6, Sun once again decided to change the name of Java platform. First, notice that the “2” has been dropped. Thus, the platform now has the name Java SE, and the official product name is Java Platform, Standard Edition 6. As with J2SE5, the 6 in the Java SE 6 is the product version number is 1.6.

1# :-> Write a program to illustrate the use of various Data Types of java.

class chap3basics {

public static void main(String[] args)

{

int lightspeed;

long days;

long seconds;

long distance;

lightspeed =186000;

days=1000;

seconds= days*24*60*60;

distance=lightspeed*seconds;

System.out .println("in"+ days+"days light will travel

about"+distance +"miles.");

char ch1,ch2;

ch1=88;

ch2='y';

System.out .println("ch1 $ch2"+ch1+" "+ch2);

ch1++;

System.out .println(ch1);

}

}

The output of the above program is as follows:-

In1000days light will travel about1607040000000miles.

Ch1 $ch2X y

Y

2# :-> Write a program to illustrate the use of boolean Type of java.

class chap3booltest {

public static void main(String[]args)

{

boolean b;

b=false;

System.out.println("b is" +b);

b=true;

System.out .println("b is "+b);

if(b)

System.out .println("this is executed coz b is true");

b= false;

if(b)

System.out .println("this will not executed coz b is false");

System.out .println("10>9"+(10>9));

System.out .println("9>10"+(9>10));

}

}

The out put of the above program is as follow:-

b is false

b is true

this is executed coz b is true

10>9true

9>10false

3# :-> Write a program to illustrate some type conversion that required casts.

class chap3conversion{

public static void main(String[]args){

byte b;

int i=257;

double d=323.134;

{System.out.println("int to byte");

b=(byte) i;

System.out.println("i $ b"+i+" "+b);

System.out.println("double to int");

i= (int) d;

System.out.println("d $ i"+d+" "+i);

System.out.println("double to byte");

b= (byte)d;

System.out.println("d $ b"+d+" "+b);

}

} }

The output of the above program is as follow:-

int to byte

i $ b 257 1

double to int

d $ I 323.134 323

double to byte

d $ b 323.134 67

4# :-> Write a program to illustrate a two-dimensional array in java.

class chap3twodarray{

public static void main(String[]args){

int twodarray[] []=new int[7][7];

int i,j,k=0,l;

for(i=0;i<6;i++)

for(j=0;j<4;j++){

twodarray[i] [j]=k;

k++;}

for(i=0;i<6;i++){

for(j=0;j<4;j++)

System.out.print(twodarray[i] [j]+ "\t ");

System.out.println();

}

}

}

The output of the above program is as follow:-

0 1 2 3

4 5 6 7

8 9 10 11

12 13 14 15

16 17 18 19

20 21 22 23

5# :-> Write a program to illustrate the bitwise logical operators.

class chap4bitlogic {

public static void main(String[] args){

String binary[]={"0000" ,"0001","0010","0011","0100","0101","0110","0111","1000",

"1001","1010","1011","1100","1101","1110","1111"};

int a=3, b=6; /** here the values of a and b are not taken from string*/

int c=a|b;

int d=a &b;

int e=a^b;

int f=(~a&b) | (a & ~b);

int g=~a &0x0f;

System.out.println("a="+"\t"+binary[a]);

System.out.println("b="+"\t"+binary[b]);

System.out.println("c="+"\t"+binary[c]);

System.out.println("d="+"\t"+binary[d]);

System.out.println("e="+"\t"+binary[e]);

System.out.println("f="+"\t"+binary[f]);

System.out.println("g="+"\t"+binary[g]);

}

}

The output of the above program is as follows:-

a= 0011

b= 0110

c= 0111

d= 0010

e= 0101

f= 0101

g= 1100

6# :-> Write a program to illustrate the switch statement.

class ch5sampleswitch{

public static void main(String[]args) {

for(int i=0;i<6;i++)

switch(i) {

case 0:

System.out.println("i is=" + i);

break;

case 1:

System.out.println("i is=" + i);

break;

case 2:

System.out.println("i is=" + i);

break;

case 3:

System.out.println("i is=" + i);

break;

default:

System.out.println("i is greater then 3" );

} }

The output of the above program is as follows:-

i is=0

i is=1

i is=2

i is=3

i is greater then 3

i is greater then 3

7# :-> Write a program to illustrate the for-each style for loop in java.

class ch5foreach {

public static void main(String args[] ) {

int num[] = {1,2,3,4,5,6,7,8,9,10 };

int sum=0;

for (int x : num) {

System.out.println("value is="+x);

sum += x;

if(x==5) break;

x= x*10; // this statement will not have any effect on for-each statement

}

System.out.println("summation:"+sum);

}

}

}

The output of the above program is as follows:-

Value is=1

Value is=2

Value is=3

Value is=4

Value is=5

Summation:15

8# :-> Write a program to illustrate the concept of classes with the help of constructor.

class box {

double width;

double height;

double depth;

box() {

width=height=depth=10;

}

box(double w,double h,double d)

{this.width=w;

height=h;

depth=d;

}

double vol(){

return width*height*depth;

}

}

class ch6boxdemo6 {

public static void main(String[] args) {

box mybox=new box(5,6,4);

box mybox2=new box();

System.out.println("the vol is " +mybox.vol());

System.out.println("the vol is " +mybox2.vol());

}

}

The output of the above program is as follows:-

The vol is 120.0

The vol is 1000.0

9# :-> Write a program to illustrate static variables, methods and blocks in java.

class ch7usestatic {

static int a = 3;

static int b;

static void meth(int x){

System.out.println("x=" +x);

System.out.println("a=" +a);

System.out.println("b=" +b);

}

static {

System.out.println("static block initilized" );

b=a*4;

}

public static void main(String[] args) {

meth(42);

}

}

The output of the above program is as follows:-

Static block initialized

X=42

a=3

b=12

10# :-> Write a program to illustrate the variable-length arguments.

class ch7varargs2 {

static void vatest(String msg, int ... v) {

System.out.print(msg+ v.length +"contents:");

for(int x: v)

System.out.print(x+" ");

System.out.println();

}

public static void main(String args[])

{

vatest("one varargs:",10);

vatest("three varargs:",1,2,3);

vatest("no varargs");

}

}

The output of the above program is as follow:-

one vararges :1contents :10

three varargs :3contents :1 2 3

no varargs 0contents:

11# :-> Write a program to illustrate the concept of inheritance using super in java.

class box{

private double width,height,depth;

box(box ob) {

width=ob.width;

height=ob.height;

depth=ob.depth;

}

box(double w,double h,double d) {

width =w;

height=h;

depth=d;

}

box() {

width = -1;

height=-1;

depth=-1;

}

box(double len) {

width=height=depth=len;

}

double volume() {

return width*height*depth;

}

}

class boxweight extends box {

double weight;

boxweight(double w,double h,double d, double m)

{super(w,h,d);

weight =m;

}

boxweight(double h,double m)

{super(h);

weight =m;

}

boxweight()

{super();

weight =-1;

}

boxweight(boxweight ob)

{super(ob);

weight =ob.weight;

}

}

class ch8demoboxweight {

public static void main(String[]args) {

boxweight ob1=new boxweight(10,12,14,19);

boxweight ob2=new boxweight(1,2,3,4);

boxweight ob3=new boxweight();

boxweight ob4=new boxweight(3,4);

boxweight ob5=new boxweight(ob2);

box boxob=new box(4);

double vol;

vol=boxob.volume();

System.out.println(" \nthe volume is:" +vol);

vol=ob1.volume();

System.out.println("\n the volume is:" +vol);

System.out.println(" \nthe weight is:" +ob1.weight);

vol=ob2.volume();

System.out.println("\n the volume is:" +vol);

System.out.println();

boxob=ob2;//a refrence variable of SUPER class can be //assigned a refrence to any SUB class

vol=boxob.volume();

System.out.println(" the volume is:" +vol);

vol=ob3.volume();

System.out.println("\n the volume is:" +vol);

vol=ob4.volume();

System.out.println("\n the volume is:" +vol);

vol=ob5.volume();

System.out.println("\n the volume is:" +vol);

}

}

The output to the above program is as follows:-

the volume is:64.0

the volume is:1680.0

the weight is:19.0

the volume is:6.0

the volume is:6.0

the volume is: -1.0

the volume is:27.0

the volume is:6.0

12# :-> Write a program to illustrate the concept of

Overriding in java.

//method overrriding.

class A {

int i,j;

A (int a, int b) {

i=a;

j=b;

}

//display i and j

void show() {

System.out.println("i and j"+i +j);

}

}

class B extends A{

int k;

B(int a,int b,int c) {

super(a,b);

k=c;

}

// display k-this overrides show() in A

void show() {

System.out.println("k ="+" "+k);

}

}

class ch8override {

public static void main(String[] args) {

B subob =new B(1,2,3);

subob.show();

}

}

The output of the above program is as follows :-

K = 3

13# :-> Write a program to illustrate the concept of

packages in java.

package mypack;

class balance {

String name;

double bal;

balance(String n, double b) {

name =n;

bal =b;

}

void show() {

if(bal<0)

System.out.print("---> ");

System.out.println(name +":$"+bal);

} }

class ch9accountbalance {

public static void main(String args[]) {

balance current[] =new balance[3];

current[0] =new balance("k.j.fielding", 123.23);

current[1] =new balance("will tell", 157.02);

current[2] =new balance("tom jackson", -12.33);

for(int i=0;i<3;i++)

current[i].show();

} }

The output of the above program is as follows:-

k.j.fielding:$123.23

will tell:$157.02

---> tom Jackson:$-12.33

14# :-> Write a program to illustrate the concept of

interfaces in java.

interface callback {

void callback(int param);

}

class client implements callback{

//implements callback interface

public void callback(int p) {

System.out.println("callback called with " +p);

}

}

class ch9testface {

public static void main(String args[]) {

callback c=new client();

c.callback(42);

}

}

The output of the above program is as follow:-

Callback called with 42

15# :-> Write a program to illustrate the concept of

Exception handling in java.

class ch10exc2 {

public static void main(String args[]) {

int d,a;

try{

d=0;

a=42/d;

System.out.println("this will not be printed.");

}

catch(ArithmeticException e) {

System.out.println("division by zero.");

}

System.out.println("after catch statement.");

}

}

The output of the above program is as follows :-

division by zero.

After catch statement.

16# :-> Write a program to illustrate the concept of

Exception handling by using throw keyword in java.

class ch10throwdemo {

static void demoproc() {

try {

throw new NullPointerException("demo");

}

catch(NullPointerException e) {

System.out.println("caught inside demoproc.");

throw e;

}

}

public static void main(String args[]) {

try {

demoproc();

}

catch(NullPointerException e) {

System.out.println("Recaught: "+e);

}

}

}

The output of the above program is as follow :-

Caught inside demoproc.

Recaught: java.lang.NullPointerException: demo

17# :-> Write a program to illustrate the concept of

Multiple threads in java.

//Create multiple threads.

class NewThread implements Runnable {

String name; // name of thread

Thread t ;

NewThread(String threadname) {

name = threadname;

t = new Thread(this, name) ;

System.out.println("New thread: "+ t) ;

t.start () ; // Start the thread

}

// This is the entry point for thread.

public void run () {

try {

for(int i = 5; i > 0; i--) {

System.out. println(name + ": " + i) ;

Thread.sleep(1000) ;

}

} catch (InterruptedException e) {

System.out.println(name + " Interrupted");

}

System.out.println(name + " exiting.");

}

}

class MultiThreadDemo {

public static void main (String args [ ] ) {

new NewThread ("One") ; // start threads

new NewThread ("Two") ;

new NewThread ("Three") ;

try {

// wait for other threads to end

Thread.sleep(10000) ;

} catch (InterruptedException e) {

System.out.println("Main thread Interrupted") ;

}

System.out.println("Main thread exiting.");

}

}

The output from this program is shown here:

New thread: Thread[One, 5,main]

New thread: Thread[Two,5,main]

New thread: Thread[Three,5,main]

One: 5

Two: 5

Three: 5

One: 4

Two: 4

Three: 4

One: 3

Three: 3

Two: 3

One: 2

Three: 2

Two: 2

One: 1

Three: 1

Two: 1

One exiting.

Two exiting.

Three exiting.

Main thread exiting.

18# :-> Write a program to illustrate the concept of enumerated data type in java.

// An enumeration of apple varieties.

enum Apple {

Jonathan, GoldenDel, RedDel, Winesap, Cortland

}

class EnumDemo {

public static void main(String args[ ])

{

Apple ap;

ap= Apple.RedDel;

// Output an enum value.

System.out.println("Value of ap: " + ap);

System.out.println();

ap = Apple.GoldenDel;

// Compare two enum values.

if(ap ==Apple.GoldenDel)

System.out.println("ap contains GoldenDel. \n");

// Use an enum to control a switch statement.

switch(ap) {

case Jonathan:

System.out.println("Jonathan is red .");

break;

case GoldenDel:

System.out.println("Golden Delicious is yellow.");

break;

case RedDel:

System.out.println("Red Delicious is red.");

break;

case Winesap:

System.out.println("Winesap is red.");

break;

case Cortland:

System.out.println("Cortland is red.");

break;

}

}

}

The output of the above program is as follows:-

Value of ap: RedDel

ap contains GoldenDel.

Golden Delicious is yellow.

19# :-> Write a program to illustrate the concept of applet in java.

import java.awt.*;

import java.applet.*;

/*

*/

public class SimpleApplet extends Applet {

public void paint(Graphics g) {

g.drawString(" A Simple Applet" , 200, 20);

}

}

To run the above code a html code is also required which is as follows:-

After running the above to codes the applet run in the window produced by SimpleApplet. The following is the content of the applet.

A Simple Applet

20# :-> Write a program to illustrate the concept of

Generics in java.

//A simple genric class

//here, t is a type parameter that

//will be replace by a real type

// when an object of type gen is created.

class Gen {

T ob; // declare an object of type T

// pass the constructor a reference to an object of type T

Gen(T o) {

ob=o;

}

//return ob.

T getob() {

return ob;

}

// show type of T.

void showtype() {

System.out.println("Type of T is " + ob.getClass().getName());

}

}

class ch14gendemo {

public static void main( String[] args) {

// create a Gen reference for the integers.

Gen iob;

/* create s Gen object and assign its reference

to iob. notice the use of autoboxing to encapsulate the value

88 within an Integer object.

*/

iob= new Gen(88);

// show the type of data used by iob.

iob.showtype();

//get the value in iob.Notice that no cast is needed

int v=iob.getob();

System.out.println("value:" +v);

System.out.println();

// create a Gen object for strings.

Gen strob = new Gen("Generics Test");

// show te type of data used by strob.

strob.showtype();

// get the value of strob.Again, notice that no cast is neede.

String str =strob.getob();

System.out.println("value: "+ str);

}

}

The output of the above program is as follows:-

Type of T is java.lang.Integer

Value:88

Type of T is java.Lang.String

Value: Generics Test