Java Using Objects from Linked HashSet Program

How to delete specific element from Linked HashSet

package com.java2novice.linkedhashset;

import java.util.LinkedHashSet;

public class MyLhsDeleteEx

{

public static void main(String a[])

{

         

        LinkedHashSet lhs = new LinkedHashSet();

        lhs.add("first");

        lhs.add("second");

        lhs.add("third");

        System.out.println(lhs);

        lhs.remove("second");

        System.out.println("Elements after deleting an element:");

        System.out.println(lhs);

    }

}

How to search an object from Linked HashSet

package com.java2novice.linkedhashset;

import java.util.LinkedHashSet;

public class MyLhsSearchEx

{

public static void main(String a[])

{

        LinkedHashSet lhs = new LinkedHashSet();

        lhs.add("first");

        lhs.add("second");

        lhs.add("third");

        System.out.println(lhs);

        System.out.println("Does set contains 'first'? "+lhs.contains("first"));

    }

}

How to eliminate duplicate user defined objects from Linked HashSet

package com.java2novice.linkedhashset;

import java.util.LinkedHashSet;

public class MyDistElementEx

{

public static void main(String a[])

{

         LinkedHashSet lhm = new LinkedHashSet();

        lhm.add(new Price("Banana", 20));

        lhm.add(new Price("Apple", 40));

        lhm.add(new Price("Orange", 30));

        for(Price pr:lhm)

        {

            System.out.println(pr);

        }

        Price duplicate = new Price("Banana", 20);

        System.out.println("inserting duplicate object...");

        lhm.add(duplicate);

        System.out.println("After insertion:");

        for(Price pr:lhm)

        {

            System.out.println(pr);

        }

    }

}

 class Price

{

    private String item;

    private int price;    

public Price(String itm, int pr)

{

        this.item = itm;

        this.price = pr;

 }

public int hashCode()

{

        System.out.println("In hashcode");

        int hashcode = 0;

        hashcode = price*20;

        hashcode += item.hashCode();

        return hashcode;

 }

 public boolean equals(Object obj)

{

        System.out.println("In equals");

        if (obj instanceof Price)

        {

            Price pp = (Price) obj;

            return (pp.item.equals(this.item) && pp.price == this.price);

        }

        else

       {

            return false;

        }

    }

 public String getItem()

{

        return item;

 }

 public void setItem(String item)

 {

        this.item = item;

  }

 public int getPrice()

 {

        return price;

  }

 public void setPrice(int price)

 {

        this.price = price;

  }

  public String toString()

 {

        return "item: "+item+"  price: "+price;

    }

}

How to find user defined objects from Linked HashSet

package com.java2novice.linkedhashset;

import java.util.LinkedHashSet;

public class MyLhsUdObjSearch

{

public static void main(String a[])

{

        LinkedHashSet lhs = new LinkedHashSet();

        lhs.add(new Price("Banana", 20));

        lhs.add(new Price("Apple", 40));

        lhs.add(new Price("Orange", 30));

        for(Price pr:lhs)

       {

            System.out.println(pr);

        }

        Price key = new Price("Banana", 20);

        System.out.println("Does set contains key? "+lhs.contains(key));

    }

}

 class Price

{

    private String item;

    private int price;

public Price(String itm, int pr)

{

        this.item = itm;

        this.price = pr;

  }

 public int hashCode()

{

        System.out.println("In hashcode");

        int hashcode = 0;

        hashcode = price*20;

        hashcode += item.hashCode();

        return hashcode;

  }

 public boolean equals(Object obj)

{

        System.out.println("In equals");

        if (obj instanceof Price)

       {

            Price pp = (Price) obj;

            return (pp.item.equals(this.item) && pp.price == this.price);

        }

        else

        {

            return false;

        }

    }

   public String getItem()

   {

        return item;

    }

    public void setItem(String item)

   {

        this.item = item;

    }

    public int getPrice()

   {

        return price;

   }

    public void setPrice(int price)

    {

        this.price = price;

    }

    public String toString()

   {

        return "item: "+item+"  price: "+price;

    }

}