Java Technology: 01/01/12

Reflect Concept (Display all methods in a class including inherited class methods)

import java.lang.reflect.Method;
public class Reflect
{
public static void main(String args[])
{
CarB ob1=new CarB();
Class c1=ob1.getClass();
Method[] meths=c1.getMethods();
for(Method m:meths)
{
System.out.println(m.getName());
}
}
}

Note: public class CarB extends Automobile implements IVehicle,IBox

output:

It displays all the methods in CarB, Automobile class

Palindrome Code

import java.util.*;
class palin12
{
public static void main(String args[])
{
String s1;
String s2="";
System.out.println("Enter the String");
Scanner scan=new Scanner(System.in);
s1=scan.next();

int l=s1.length();
char c[]=new char[l];
for(int i=l-1;i>=0;i--)
{
c[i]=s1.charAt(i);
s2=s2+c[i];
}
System.out.println(s2);
if(s1.equals(s2))
{
System.out.println("palindrome");
}
else
{
System.out.println("not palindrome");
}
}
}

output:
Enter the String

malayalam
malayalam
palindrome

Enter the String
bharath
htarahb
not palindrome

Passing Variable Length Arguments using ...

Ambiguity may occur in this method.

PassMulti.java:

class PassMulti
{

/*public void PassTest(int ... v)
{
System.out.println("No of args:" + v.length);
for(int i:v)
System.out.println(i);
}
*/

public void PassTest(double ... v)
{
System.out.println("No of args:" + v.length);
for(double i:v)
System.out.println(i);
}

public void PassTest(int a,boolean ... v)
{
System.out.println("No of args:" + v.length);
System.out.println(a);
for(boolean i:v)
System.out.println(i);
}

public void PassTest(String ... v)
{
System.out.println("No of args:" + v.length);
for(String i:v)
System.out.println(i);
}

}

PassMultiDemo.java

public class PassMultiDemo
{
public static void main(String args[])
{
//int a[]={10,20,30};
//int b[]={5,6};
//int c[]={};
PassMulti ob1=new PassMulti();
PassMulti ob2=new PassMulti();
PassMulti ob3=new PassMulti();

ob1.PassTest(1,2,3,4,5);
ob2.PassTest(10.20,50.5,70.00);
ob3.PassTest(10,true,false);
ob3.PassTest("Bharath","Hussain");

}
}

output:

javac PassMulti.java

javac PassMultiDemo.java

java PassMulti

No of args:5

1.0

2.0

3.0

4.0

5.0

No of args:3

10.2

50.5

70.0

No of args:2

true

false

No of args:2

Bharath

Hussain

Passing Variable Length Arguments using array

PassArray.java:

public class PassArray
{

public void PassTest(int v[])
{
System.out.println("No of args:" + v.length);
for(int i:v)
System.out.println(i);
}

public void PassTest(double v[])
{
System.out.println("No of args:" + v.length);
for(double i:v)
System.out.println(i);
}

public void PassTest(String v[])
{
System.out.println("No of args:" + v.length);
for(String i:v)
System.out.println(i);
}

}

PassArrayDemo.java

public class PassArrayDemo
{
public static void main(String args[])
{
int a[]={10,20,30};
String b[]={"Bharath","Hussain"};
double c[]={20.5};
double d[]={10.5,25.6,20};
PassArray ob1=new PassArray();
//PassArray ob2=new PassArray();
//PassArray ob3=new PassArray();
//PassArray ob4=new PassArray();
ob1.PassTest(a);
ob1.PassTest(b);
ob1.PassTest(c);
ob1.PassTest(d);
}
}

output:

javac PassArray.java

javac PassArraydemo.java

java PassArray

No of args:3

No of args:2

Bharath

Hussain

No of args:1

20.5

No of args:3

10.5

25.6

20.0

For Loop - Triangle

class Triangle1
{
public static void main(String args[])
{
for(int j=0;j<10;j++)
{
for(int i=10;i>j;i--)
System.out.print(".");
for(int k=j;k>=1;k--)
System.out.print(k);
System.out.println();
}
}
}

output:
..........
.........1
........21
.......321
......4321
.....54321
....654321
...7654321
..87654321
.987654321

class Triangle2
{
public static void main(String args[])
{

for(int j=0;j<10;j++)
{
for(int i=10;i>j;i--)
System.out.print(" ");

for(int k=j;k>=1;k--)
System.out.print(k);

for (int m=2;m<(j+1);m++)
System.out.print(m);

System.out.println();
}

}
}

output:

1
212
32123
4321234
543212345
65432123456
7654321234567
876543212345678
98765432123456789

class Triangle3
{
public static void main(String args[])
{
for(int j=1;j<10;j++)
{
for(int i=10;i>j;i--)
System.out.print(" ");

for(int k=j;k>=1;k--)
System.out.print(k);

for (int m=2;m<(j+1);m++)
System.out.print(m);

System.out.println();
}

for(int j=9;j>1;j--)
{
for(int i=10;i>=j;i--)
System.out.print(" ");

for(int k=j-1;k>=1;k--)
System.out.print(k);

for (int m=2;m<(j);m++)
System.out.print(m);

System.out.println();

}
}
}

output:

1
212
32123
4321234
543212345
65432123456
7654321234567
876543212345678
98765432123456789
876543212345678
7654321234567
65432123456
543212345
4321234
32123
212
1

class Triangle4
{
public static void main(String args[])
{

for(int j=1;j<10;j++)
{
for(int i=10;i>j;i--)
System.out.print(" ");

for(int k=j;k>=1;k--)
System.out.print(" " +k);

for (int m=2;m<(j+1);m++)
System.out.print(" " +m);

System.out.println();
}

for(int j=9;j>1;j--)
{
for(int i=10;i>=j;i--)
System.out.print(" ");

for(int k=j-1;k>=1;k--)
System.out.print(" "+k);

for (int m=2;m<(j);m++)
System.out.print(" "+m);

System.out.println();
}
}
}
output:

1
2 1 2
3 2 1 2 3
4 3 2 1 2 3 4
5 4 3 2 1 2 3 4 5
6 5 4 3 2 1 2 3 4 5 6
7 6 5 4 3 2 1 2 3 4 5 6 7
8 7 6 5 4 3 2 1 2 3 4 5 6 7 8
9 8 7 6 5 4 3 2 1 2 3 4 5 6 7 8 9
8 7 6 5 4 3 2 1 2 3 4 5 6 7 8
7 6 5 4 3 2 1 2 3 4 5 6 7
6 5 4 3 2 1 2 3 4 5 6
5 4 3 2 1 2 3 4 5
4 3 2 1 2 3 4
3 2 1 2 3
2 1 2
1

Spliting the commandline String and storing it in charArray and prints its Ascii Value of each Character

public class CharA
{
public static void main(String args[])
{
int[] j=new int[100];
String str=args[0];
char[] cs=str.toCharArray();
System.out.println("length=" + str.length());
for(int i=0;i<str.length();i++)
{
System.out.print(cs[i]);
j[i]=(int)(cs[i]);
System.out.println(" " + j[i]);
}
}
}

output:
java CharA "Hello World"
length=11

H 72
e 101
l 108
l 108
o 111
32
W 87
o 111
r 114
l 108
d 100

Spliting words using Split method and print no. of words in a given String and Reverse the Words

public class SplitB
{
public static void main(String args[])
{
String s1=args[0];
String[] str=s1.split(" ");
System.out.println(args[0]);
//int size=(java.util.Arrays.asList(str).size());
int size=str.length;
System.out.println("No of words=" + size);
for(int i=0;i<size;i++)
System.out.println(str[i]);
System.out.println("Reverse words:");
for(int i=size-1;i>=0;i--)
System.out.println(str[i]);
}
}

output:
java SplitB "Hello World"

Hello World
No of words=2
Hello
World
Reverse words:
World
Hello

Passing Parameters in Command Line

public class SampleB
{
public static void main(String args[])
{
String s1=args[0];
String s2=args[1];
System.out.println("s1=" + s1 + "s2=" + s2);
System.out.println("s1+s2=" + s1+s2);

int c1=Integer.parseInt(s1);
int c2=Integer.parseInt(s2);
System.out.println("c1=" + c1 + "c2=" +c2);
System.out.println("c1+c2=" + (c1+c2));
}
}

output:
java SampleB 10 20

s1=10s2=20
s1+s2=1020
c1=10c2=20
c1+c2=30

Finding Age Code

import java.util.*;
public class DateDemoA
{
public static void main(String args[])
{
Date d1=new Date();
System.out.println("Current Date:" + d1);
Date d2=new Date(84,12,01); //YY,MM,DD
System.out.println("Date of Birth:" + d2);
int age=d1.getYear()-d2.getYear();
System.out.println("Age:" + age);
int x=d2.compareTo(d1); //Big with smaller==> +1 //small with big==> -1
System.out.println(x);
}
}

output:

Current Date:Tue Dec 13 20:45:31 IST 2011
Date of Birth:Tue Jan 01 00:00:00 IST 1985
Age:26
-1

Encoding Code

Encoding a Single Character:

class Encode
{
public static void main(String args[])
{
char s1='a';
int j;
j=(int)s1 + 10;
System.out.println(" "+j);
char s2;
s2= (char)j;
System.out.println(j+" is "+s2);
}
}

output:

107
107 is k

Encoding a String:

class Encode1
{
public static void main(String args[])
{
String s1="BHARATH";
int a[]=new int [10];
char b[]=new char [10];
int len=s1.length();
for(int i=0; i<=len-1;i++)
{
a[i]=(int)s1.charAt(i) + 10;
b[i]=(char)a[i];
}
for(int i=0;i<=len-1;i++)
{

System.out.println(a[i]);
}
for(int i=0;i<=len-1;i++)
{
System.out.print(b[i]);
}
}
}

output:

76
82
75
92
75
94
82
LRK\K^R

Sunday, January 1, 2012