Java Programs
* STRING
SORT*
import
java.util.Arrays;
public
class GFG
{
public static String sortString(String
inputString)
{
char tempArray[] =
inputString.toCharArray();
Arrays.sort(tempArray);
return new
String(tempArray);
}
public
static void main(String[ ] args)
{
String inputString = "geeksforgeeks";
String outputString = sortString(inputString);
System.out.println("Input String : " + inputString);
System.out.println("Output String : " + outputString);
}
}
OUTPUT:
Input String : geeksforgeekss
Output String : eeeefggkkorss
*MATRIX MULTIPLICATION*
import java.lang.*;
import java.io.*;
class multiplication
{
static int N = 4;
static void multiply(int mat1[ ][ ],int
mat2[ ][ ], int result[ ][ ])
{
int i, j, k;
for (i = 0; i < N; i++)
{
for (j = 0; j < N; j++)
{
result[i][j] = 0;
for (k = 0; k < N;
k++)
result[i][j] +=
mat1[i][k] * mat2[k][j];
}
}
}
public static void main(String[ ] args)
{
int mat1[ ][ ] = { { 1, 1, 1, 1 },
{ 2, 2, 2,
2 },
{ 3, 3, 3, 3 },
{ 4, 4, 4,
4 } };
int mat2[ ][ ] = { { 1, 1, 1, 1 },
{ 2, 2, 2,
2 },
{ 3, 3, 3,
3 },
{ 4, 4, 4, 4 } };
int result[ ][ ] = new int[N][N];
int i,
j;
multiply(mat1, mat2, res);
System.out.println("Result
matrix" + " is ");
for (i = 0; i < N; i++)
{
for (j = 0; j < N; j++)
System.out.print(res[i][j]
+ " ");
System.out.println( );
}
}
}
OUTPUT:
Result matrix is
10 10
10 10
20
20 20 20
30
30 30 30
40
40 40 40
*CONSTRUCTOR*
import java.io.*;
public class Constructor
{
double
width,height,depth;
Constructor( )
{
System.out.println(“Constructor without parameter”);
width=10;
height=10;
depth=10;
}
Constructor(int
a, int b,int c)
{
System.out.println(“Constructor with parameter”);
width=a;
height=b;
depth=c;
double
volume( )
{
return width * height * depth;
}
}
class
ConstructorDemo
{
public
static void main(String args[ ])
{
Constructor Con = new Constructor( );
double vol;
vol=
Con.volume( );
System.out.println(“Volume is “+vol);
Constructor Con1 = new Constructor(8,11,9);
vol=Con1.volume( );
System.out.println(“Volume is “+vol);
}
}
OUTPUT:
Constructor without parameter
Volume is 1000
Constructor with
parameter
Volume is 792
*METHOD OVERLOADING*
import
java.lang.*;
import
java.io.*;
class Shape
{
static final double PI = Math.PI;
void Area(float a)
{
float A = a * a;
System.out.println("Area
of the Square: " + A);
}
void Area(double a)
{
double A = PI * a * a;
System.out.println("Area
of the Circle: " + A);
}
void Area(int a, int b)
{
int A = a * b;
System.out.println("Area
of the Rectangle: " + A);
}
}
class overloading
{
public static void main(String[] args)
{
Shape
obj = new Shape();
obj.Area(10.5);
obj.Area(3);
obj.Area(5,
4);
}
}
OUTPUT:
Area of the Circle: 346.36059005827474 Area of the Square: 9.0 Area of the Rectangle: 20
*METHOD OVERRIDING*
import java.io.*;
class Parent
{
void show( )
{
System.out.println("Parent's show(
)");
}
}
class Child extends Parent
{
void show( )
{
System.out.println("Child's show(
)");
}
}
class Main
{
public static void main(String[ ] args)
{
Parent obj1 = new Parent( );
obj1.show( );
Parent obj2 = new Child( );
obj2.show( );
}
}
OUTPUT:
Parent's show( )
Child's show( )
MULTIPLE
INHERITANCE*
import java.io.*;
interface Backend
{
public void connectServer( );
}
class Frontend
{
public void responsive(String str)
{
System.out.println(str + " can
also be used as frontend.");
}
}
class Language extends
Frontend implements Backend
{
String language = "Java";
public void connectServer( )
{
System.out.println(language + "
can be used as backend
language.");
}
public static void main(String[ ] args)
{
Language java = new Language( );
java.connectServer( );
java.responsive(java.language);
}
}
OUTPUT:
Java
can be used as backend language
Java can
also be used as frontend
*EXCEPTION HANDLING*
import java.io.*;s
import java.lang.*;
class Main
{
public static void main(String args[])
{
int val1, val2;
try
{
System.out.println("Try
Block:: Start");
val1 = 0;
val2 = 25
/ val1;
System.out.println(val2);
System.out.println("Try
Block:: End");
}
catch (ArithmeticException
e)
{
System.out.println("ArithmeticException
:: Divide by Zero!!");
}
System.out.println("Outside
try-catch:: Rest of the code.");
}
}
OUTPUT:
Try Block:: Start
ArithmeticException :: Divide by
Zero!!
Outside try-catch:: Rest of the code.
*MULTITHREADING *
import java.io.*;
class
ABC implements Runnable
{
public void run( )
{
try
{
Thread.sleep(100);
}
catch (InterruptedException ie)
{
ie.printStackTrace( );
}
System.out.println("The state of
thread t1 while it invoked the
method join( ) on thread t2 -"+
ThreadState.t1.getState( ));
try
{
Thread.sleep(200);
}
catch (InterruptedException ie)
{
ie.printStackTrace( );
}
}
}
public class ThreadState implements
Runnable
{
public static Thread t1;
public static ThreadState obj;
public static void main(String args[
])
{
obj = new ThreadState( );
t1 = new Thread(obj);
System.out.println("The state of thread
t1 after spawning it - " +
t1.getState( ));
t1.start( );
System.out.println("The state of thread
t1 after invoking the
method start( ) on it
- " + t1.getState( ));
}
public void run( )
{
ABC myObj = new ABC();
Thread t2 = new Thread(myObj);
System.out.println("The state of
thread t2 after spawning it - "+
t2.getState( ));
t2.start( );
System.out.println("the state of
thread t2 after calling the
method start( ) on it - " + t2.getState(
));
try
{
Thread.sleep(200);
}
catch (InterruptedException ie)
{
ie.printStackTrace( );
}
System.out.println("The state of
thread t2 after invoking the
method sleep( ) on it - "+ t2.getState( )
);
try
{
t2.join( );
}
catch (InterruptedException ie)
{
ie.printStackTrace( );
}
System.out.println("The state of thread
t2 when it has completed it's
execution -
" + t2.getState( ));
}
}
OUTPUT:
The state of thread t1 after spawning it - NEWThe state of thread t1 after invoking the method start() on it - RUNNABLEThe state of thread t2 after spawning it - NEWthe state of thread t2 after calling the method start() on it - RUNNABLEThe state of thread t1 while it invoked the method join() on thread t2 -TIMED_WAITINGThe state of thread t2 after invoking the method sleep() on it - TIMED_WAITINGThe state of thread t2 when it has completed it's execution - TERMINATED
*CREATING A BOOK STRUCTURE *
import java.io.*;
class Book
{
private String title;
private String author;
private int pages;
private String publisher;
private int year;
public Book(String title, String author,
int pages, String publisher,
int
year)
{
this.title = title;
this.author = author;
this.pages = pages;
this.publisher = publisher;
this.year = year;
}
public Book(Book book)
{
this.title = book.title;
this.author = book.author;
this.pages = book.pages;
this.publisher = book.publisher;
this.year = book.year;
}
public String getTitle( )
{
return title;
}
public void setAuthor(String author)
{
this.author = author;
}
public boolean equals(Object o)
{
if (!(o instanceof Book))
{
return false;
}
Book other = (Book) o;
if (this.title.equals(other.title)
&&
this.author.equals(other.author)
&&
this.publisher.equals(other.publisher) &&
this.pages == other.pages
&& this.year == other.year)
{
return true;
}
return false;
}
public String toString( )
{
return String.format("%-10s
%s\n", "Title:", title) +
String.format("%-10s
%s\n", "Author:", author) +
String.format("%-10s
%d\n", "Pages:", pages) +
String.format("%-10s
%s\n", "Publisher:", publisher) +
String.format("%-10s %d",
"Year:", year);
}
}
public class Main
{
public static void main(String[ ] args)
{
Book first = new Book("The
Book", "Famous Writer", 199, "Big
Book Publisher", 1984);
Book second = new Book("The Second
Book", "Less F. Writer",
249, "The Book Publishers", 1999);
System.out.println("First book");
System.out.println(first +
"\n");
System.out.println("Second
book");
System.out.println(second +
"\n");
System.out.println("Title of the
first book: " + first.getTitle( ) +
"\n");
Book firstCopy = new Book(first);
System.out.println("Copy of the
first book:");
System.out.println(firstCopy +
"\n");
System.out.println("Copy equals
first book: " +
firstCopy.equals(first));
System.out.println("Second book
equals first book: " +
second.equals(first));
System.out.println( );
System.out.println("Change writer
of the copy to :'Most F.
Writer'");
firstCopy.setAuthor("Most F.
Writer");
System.out.println(firstCopy +
"\n");
System.out.println("Copy equals
first book: " +
firstCopy.equals(first));
}
}
OUTPUT:
First book Title: The Book Author: Famous Writer Pages: 199 Publisher: Big Book Publisher Year: 1984 Second book Title: The Second Book Author: Less F. Writer Pages: 249 Publisher: The Book Publishers Year: 1999 Title of the first book: The Book Copy of the first book: Title: The Book Author: Famous Writer Pages: 199 Publisher: Big Book Publisher Year: 1984 Copy equals first book: true Second book equals first book: false Change writer of the copy to :'Most F. Writer' Title: The Book Author: Most F. Writer Pages: 199 Publisher: Big Book Publisher Year: 1984 Copy equals first book: false*JDBC
CONNECTION *
import
java.sql.*;
public class GFG
{
public static void main(String arg[ssss])
{
Connection connection = null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
connection =
DriverManager.getConnection(
"jdbc:mysql://localhost:3306/mydb",
"mydbuser",
"mydbuser");
Statement statement;
statement =
connection.createStatement );
ResultSet resultSet;
resultSet = statement.executeQuery(
"select *
from designation");
int code;
String title;
while (resultSet.next( ))
{
code =
resultSet.getInt("code");
title =
resultSet.getString("title").trim();
System.out.println("Code :
" + code + " Title : " +
title);
}
resultSet.close( ), statement.close( ),connection.close( );
}
catch (Exception exception)
{
System.out.println(exception);
}
}
}}
OUTPUT:
java.lang.sClassNotFoundException: com.mysql.cj.jdbc.Driver
Comments
Post a Comment