Java Enums

1)  Enums were introduced in java 5.0. Enums restrict a variable to have one of only a few predefined values.

2)  The values in this enumerated list are called enums.

3)  With the use of enums, it is possible to reduce the number of bugs in your code.

4)  For example, if we consider an application for a fresh juice shop, it would be possible to restrict the glass size to

5)  small, medium and large. This would make sure that it would not allow anyone to order any size other than the small, medium or large

class FreshJuice{
enum FreshJuiceSize{ SMALL, MEDUIM, LARGE }
FreshJuiceSize size;
}
public class FreshJuiceTest{
public static void main(String args[]){
FreshJuice juice =new FreshJuice();
juice.size =FreshJuice.FreshJuiceSize.MEDUIM ;

System.out.println("juice size"+" "+juice.size);
}
}

Bubble Sort

bubble sort

import java.io.*;

class Bubblesort

{

public static void main(String args[])

{

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

int n=0,i,j,t;

int a[]=new int[10];

System.out.println("Enter size of the array:");

try

{

n=Integer.parseInt(br.readLine());

}

catch(Exception e) {}

System.out.println("Enter elements into the array:");

try

{

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

a[i]=Integer.parseInt(br.readLine());

}

catch(Exception e) {}

for(i=0;i<n-1;i++)

for(j=0;j<n-1-i;j++)

if(a[j]>a[j+1])

{

t=a[j];

a[j]=a[j+1];

a[j+1]=t;

}

System.out.println("The sorted array is:");

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

System.out.println(a[i]);

}

}

Output:

javac Bubblesort.java

java Bubblesort

Enter the size of array

5

Enter the elements into the array

45

34

76

12

69

The sorted array is

12 34 45 69 76

Selection sort

selection sort

import java.io.*;

class Selectionsort

{

public static void main(String args[])

{

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

int n=0,i,j,t;

int a[]=new int[10];

System.out.println("Enter size of the array:");

try

{

n=Integer.parseInt(br.readLine());

}

catch(Exception e){}

System.out.println("Enter elements into the array:");

try

{

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

a[i]=Integer.parseInt(br.readLine());

}

catch(Exception e){}

i=0;

while(i<n-1)

{

int key=i;

for(j=i+1;j<n;j++)

{

if(a[j]<a[key])

{

key=j;

}

}

t=a[key];

a[key]=a[i];

a[i]=t;

i++;

}

System.out.println("The sorted array is:");

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

System.out.println(a[i]);

}

}

Output:

javac Selectionsort.java

java Selectionsort

Enter the size of array

5

Enter the elements into the array

45

34

76

12

69

The sorted array is

76 69 45 34 12

Binary Search

Binary Search

import java.lang.*;

import java.util.*;

import java.io.*;

class Search

{

public int binarysearch(int[]a,int key)

{

int f=1;

int low=0;

int high=a.length-1;

int mid=(low+high)/2;

while(low<=high)

{

if(a[mid]==key)

{

f=0;

break;

}

if(a[mid]<key)

low=mid+1;

else

high=mid-1;

mid=(low+high)/2;

}

return(f);

}

}

class Binarysearch

{

public static void main(String args[])

{

Scanner sc=new Scanner(System.in);

Search s=new Search();

int[]a;

int i,k,n;

int f=1;

System.out.println("Binary search");

System.out.println("enter your choice");

System.out.println("Enter the size of array");

n=sc.nextInt( );

a=new int[n];

System.out.println("Enter the elements");

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

a[i]=sc.next();

System.out.println("Enter the element to search:");

k=sc.nextInt();

int c=s.binarysearch(a,k);

if(c==0)

System.out.println("The element is found");

else

System.out.println("The elements is not found");

}

}

Output:

javac Binarysearch.java

java Binarysearch

BINARY SEARCH

Enter your choice

Enter the size of array

5

Enter the elements into the array

2

4

1

8

9

Enter the element to search

8

The element is found

Output:

javac Binarysearch.java

java Binarysearch

BINARY SEARCH

Enter your choice

Enter the size of array

5

Enter the elements into the array

2

4

1

8

9

Enter the element to search

10

The element not found

Linear search

 Linear search

import java.lang.*;

import java.util.*;

import java.io.*;

class Search

{

public int linearsearch(int[]a,int key)

{

int flag=1;

for(int i=0;i<a.length;i++)

{

if(a[i]==key)

{

flag=0;

}

}

return(flag);

}

}

class Linearsearch

{

public static void main(String args[])

{

Scanner sc=new Scanner(System.in);

{

Search s=new Search( );

int []a;

int i,k,n,ch;

int f=1;

System.out.println("Linear Search\n");

System.out.println("Enter the size of array");

n=sc.nextInt( );

a=new int[n];

System.out.println("enter the elements");

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

a[i]=sc.nextInt( );

System.out.println("enter the element to search");

k=sc.nextInt( );

f=s.linearsearch(a,k);

if(f==0)

System.out.println("The element is found");

else

System.out.println("Element is not found");

}

}

}

Output:

javac Linearsearch.java

java Linearsearch

LINEAR SEARCH

Enter your choice

Enter the size of array

5

Enter the elements into the array

2

4

1

8

9

Enter the element to search

8

The element is found

Output:

javac Linearsearch.java

java Linearsearch

LINEAR SEARCH

Enter your choice

Enter the size of array

5

Enter the elements into the array

2

4

1

8

9

Enter the element to search

10

The element not found