Wrapper classes

The classes which are used to convert the string value (Actually numeric) into it's respective data type, are called as wrapper classes.

Classes

• Integer
• Float
• Character
• Long
• Short
• Byte
• Boolean
• Double

And there respective static parsing methods are :

• parseInt()
• parsefloat()
• parselong()
• parseShort()
• parseDouble()
• parseByte()
• parseChar()
• parseBoolean()

Integer.parseInt()

It converts the string value into integer type.

float.parsefloat()

It converts the string value into float type.

Write a program to print addition of two numbers passed through command line.

class Add1
{
 public static void main(String args[])
 {
  int n=args.length;
  if(n>1)
  {
  int a,b,c;
  a=Integer.parseInt(args[0]);
  b=Integer.parseInt(args[1]);
  c=a+b;
  System.out.println("Addition is "+c);
  }
         else
   System.out.println("Please enter two arguments");
 }
}

How To Run ?
javac Add1.java
java Add1 10 30