Hi all,
I am implementing module for a scenario where there is a Stock of Products which can be veiwed and added to shopping cart. I am using collections for this , just for sake of practicing Collections.
I am stuck at a point .
For implementation purpose , i have implemented following classes :
Product
Stock
See
MyHashMap
The issue is , MyHashMap extends HashMap and is actually implemented as an ArrayList of LinkedLists .In See i call view_all() , there on converting the mmap (instance of MyHashMap ) to Set
it seems there are no elemnets in the Set as is displayed from output of line 48(comment)
//package p1;
import java.util.*;
import java.io.*;
import java.text.*;
public class Master
{
public static void main(
String args[])
{
InputStreamReader ir=new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(ir);
System.out.println("\n to buy hit 1 \n to window shop hit 2 \n to add to stock hit 3");
try{
Integer i= Integer.valueOf(br.readLine());
switch(i)
{
/*case 1:new Buy().buy();
break;*/
case 2:Stock.addStock();//////////NOTICE effect of sequencing in switch
case 3:new See().see();
//break;
//case 2:new Stock().addStock();
//break;
//default:System.out.println("No valid option chosen");
}
}
catch(Exception ex)
{
ex.printStackTrace();
}
finally
{
System.out.println("You would veiw relevant output shortly");
}
}
}
//////////////////////////////
/*public class CustomColls
{*/
/*static*/ class MyHashMap extends HashMap /* ASK here if i add the generic types in the declaration , as done initially*/
{
//static LinkedList<Product> ArrayList=new ArrayList(LinkedList<Product>);
//LinkedList<Product> []arr=(LinkedList<Product>)arr1;
LinkedList<Product> temp= new LinkedList<Product>();
MyHashMap(){
for(int i=0;i<9;i++)// initialising an array of empty ArrayLists
{
LinkedList<Product> ll= new LinkedList<Product>();
Stock.al.add(i,ll);
}}
public Object put( Object i, Object p)
{
Integer key =(Integer)i;
System.out.println("PUT 111111"+(key%1000));
Product value= (Product)p;
System.out.println("PUT 2222222");
temp=Stock.al.get(key%10);
System.out.println("PUT 333333");
temp.add((Product)p);
System.out.println("PUT 4444444");
System.out.println("added to list");
Stock.count[key%10]++;
Product.count++;
return temp;
}
public LinkedList<Product> get(Object key)
{
Integer i=(Integer)key;
return Stock.al.get(i%10);//////ASK why didn't (Integer)key%10 work???
}
/*boolean get(K k)
{on lync
List l=*/
}
//////////////////////////
class Product
{ static int count=0;
private String gender;
private String category;
private String color;
private int barcode;
private float price;
private int discount;
private String brand;
private Date DateofArrival;
public Date getDateofArrival()
{
return this.DateofArrival;
}
public void setDateofArrival(Date d)
{
this.DateofArrival=d;
}
public String getGender()
{
return this.gender;
}
public String getCategory()
{
return this.category;
}
public String getColor()
{
return this.color;
}
public int getBarcode()
{
return this.barcode;
}
public float getPrice()
{
return this.price;
}
public String getBrand()
{
return this.brand;
}
public void setDiscount(Integer i)
{
this.discount=i;
}
public void setGender(String b)
{
this.gender=b;
}
public void setCategory(String b)
{
this.category=b;
}
public void setColor(String b)
{
this.color=b;
}
public void setBarCode(int b)
{
this.barcode=b;
}
public void setPrice(float b)
{
this.price=b;
}
public void setBrand(String b)
{
this.brand=b;
}
/*public String getGender()
{
return this.gender;
}
public String getGender()
{
return this.gender;
}*/
public int hashCode()
{
int gen=0,cat=0;
String gender=this.getGender().toUpperCase();
String category=this.getCategory().toUpperCase();
for(int i=0;i<gender.length();i++)
gen+=(int)gender.charAt(i);
for(int i=0;i<category.length();i++)
cat+=(int)category.charAt(i);
return(gen+cat);
}
public boolean equals(Product p)
{
//boolean val=false;
System.out.println("in equals");
if((this.getGender().equalsIgnoreCase(p.getGender()))&&(this.getCategory().equalsIgnoreCase(p.getCategory()))&&(this.getColor().equalsIgnoreCase(p.getColor()))&&(this.getColor().equalsIgnoreCase(p.getColor()))&&(this.getBarcode()==p.getBarcode())&&(this.getPrice()==p.getBarcode()))
return true;
else
return false;
}
}
///////////////////////////////////
class Stock
{
static int count[]=new int[9];
static ArrayList <LinkedList<Product>>al =new ArrayList<LinkedList<Product>>();
//static LinkedList<Product> array[]=new LinkedList[8];
static MyHashMap mmap=new MyHashMap();
/// see whether changes to the Map are reflected in its corresponding Collection
public static void addStock()
{
String str="";
//String inputz[]=new String[8];
InputStreamReader ir=new InputStreamReader(System.in);
BufferedReader br= new BufferedReader(ir);
SimpleDateFormat formatter= new SimpleDateFormat("dd-mm-yyyy");
try
{
System.out.println("maximum of 8 objs cn b inserted");
System.out.println("no. of objs to b inserted");
int c=Integer.valueOf(br.readLine());
for(int i=1;i<=c;i++)
{
/*private String gender;
private String category;
private String color;
private int barcode;
private float price;
private String discount;
private String brand;
private Date DateofArrival;*/
Product p= new Product();
System.out.println("gender,category,color,barcode,price,discount,brand,DateofArrival?");
str+=br.readLine();
String[]inputz=str.split(",");
System.out.println("has read line");
p.setGender((String)inputz[0]);
System.out.println("first in");
p.setCategory(inputz[1]);
p.setColor(inputz[2]);
p.setBarCode(Integer.valueOf(inputz[3]));
System.out.println("2nd in");
p.setPrice(Integer.valueOf(inputz[4]));
System.out.println("3rd in");
p.setDiscount(Integer.valueOf(inputz[5]));
System.out.println(p+""+""+"sm props set");
p.setBrand(inputz[6]);
p.setDateofArrival(formatter.parse(inputz[7]));
System.out.println(p+""+""+"has been set");
LinkedList<Product> itemz=(LinkedList<Product>)mmap.put(new Integer(p.hashCode()),p);
System.out.println(p+""+""+p.hashCode()+"has been added");
System.out.println(itemz);
}
}
catch(Exception e)
{
System.out.println("error");/////////////////ASK: hw cm its running without a try
e.printStackTrace();
}
}
}
////////////////////////////////////////////////////////////////////////////////////////////
class See{
//Collection<ArrayList<LinkedList<Product>>> c= Stock.mmap.values();///////////ASK why didn;t dis wrk ???
//ArrayList<LinkedList<Product>> c= (ArrayList<LinkedList<Product>>)Stock.mmap.values();
//System.out.println(c);
Iterator it=Stock.mmap.entrySet().iterator();
public void see() throws Exception
{
System.out.println("Select your options for the order in which you want to see the items\n 1:View all \n 2 :View price wise \n 3:view Brand wise\n 4:View latest arrivals");
InputStreamReader ir=new InputStreamReader(System.in);
BufferedReader br=new BufferedReader(ir);
Integer i=Integer.valueOf(br.readLine());
switch(i)
{
case 1:view_all();
break;
/*case 2:view_pricewise();
break;
case 3:view_brandwise();
break;
case 4:view_latest();*/
}
}
public void view_all(){
//for(int i=0;i<
System.out.println(it.hasNext());///////////
LINE 48
while(it.hasNext()){
System.out.println("ll");
//for(LinkedList<Product> ll :c)
LinkedList<Product> ll=(LinkedList<Product>)it.next();
System.out.println(ll.peekFirst().getBrand());
//ListIterator<Product> li=ll.listIterator(0);
Iterator lt=ll.iterator();
while(lt.hasNext())
{
//LinkedList<Product> ll=li.next();
Product p=(Product)lt.next();
System.out.println(p.getGender()+"\n"+p.getCategory()+"\n"+p.getPrice()+"\n"+p.getColor()+"\n"+p.getBrand());
}
}
}
/*public void view_pricewise(){};
public void view_brandwise(){};
public void view_latest(){};*/
}
Where has it gone wrong ???
