Java:j'ai pb avec mon if statements

import java.io.*;
public class Purchase 
{
	double bill;
	String str;
	String str_discount="";
	public Purchase()
	{ 
		try
		{ 
			BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
			System.out.println("Enter the amount of bill:");
			bill=Double.parseDouble(br.readLine());
			System.out.println("Enter the types of clothe");
			str=br.readLine();
			
			if(str.equalsIgnoreCase("handloom"))
			{ 
				if(bill>=0&& bill <=100)
				{ 
					bill=bill-(bill*5)/100;
					str_discount="5%";
				}
				if(bill>=100&& bill <=200)
				{ 
					bill=bill-(bill*7.5)/100;
					str_discount="7.5%";
				}
				if(bill>200&& bill <=300)
				{ 
					bill=bill-(bill*10)/100;
					str_discount="10%";
				}
				if(bill>300)
				{ 
					bill=bill-(bill*15/100);
					str_discount="15%";
				}
				
				}
			if(str.equalsIgnoreCase("mill"))
			{
		System.out.println("enter");
		{ 
			if(bill>=0&& bill <=100)
			{ 
				bill=bill;
				str_discount="0%";
			}
			if(bill>=100&& bill <=200)
			{ 
				bill=bill-(bill*5)/100;
				str_discount="5%";
			}
			if(bill>200&& bill <=300)
			{ 
				bill=bill-(bill*7.5)/100;
				str_discount="7.5%";
			}
			if(bill>300)
			{ 
				bill=bill-(bill*10/100);
				str_discount="10%";
			}
		}
		System.out.println("The discount is:"+str_discount);
		System.out.println("The final bill after discount is:"+bill);
		}}
			catch(Exception e)
			{ 
				System.out.println("Exception is:"+e);
			}
		    }
	public static void main (String args[])
	{
	
	{
		Purchase pur=new Purchase();
	}
	}}