Knapsack Java

Knapsack Using Greedy Algorithm

Code:
package com.nearur;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
public class KNAPSACK {
 static int capacity=40;

 public static void main(String[] args) {
package com.nearur;

public class Item {

String name;
int value,weight;
public Item(String name, int value, int weight) {
super();
this.name = name;
this.value = value;
this.weight = weight;
}

int compareWeight(Item x) {
if(x.weight>weight) {
return -1;
}return 1;
}

int compareValue(Item x) {
if(x.value>value) {
return 1;
}return -1;
}

int compareratio(Item x) {
if(x.value/x.weight>value/weight) {
return 1;
}return -1;
}

}

  Item [] item=new Item[4];
  item[0]=new Item("I1",100,20);
  item[1]=new Item("I2",90,10);
  item[2]=new Item("I3",40,15);
  item[3]=new Item("I4",50,5);

  ArrayList<Item> knapsack=new ArrayList<>();
  ArrayList<Item> allitems=new ArrayList<>();

  for(int i=0;i<item.length;i++) {
   allitems.add(item[i]);
  }

  Comparator<Item> com=new Comparator<Item>() {
 
   @Override
   public int compare(Item o1, Item o2) {
    return o1.compareratio(o2);
    //return o1.compareValue(o2);
    //return o1.compareWeight(o2);
   }
  };

  Collections.sort(allitems,com);

  for(Item ite:allitems) {
   System.out.println(ite.name);
   if(ite.weight<=capacity) {
    knapsack.add(ite);
    capacity=capacity-ite.weight;
   }
  }

  int mvalue=0,mweight=0;

  for(Item i: knapsack) {
   mvalue +=i.value;
   mweight +=i.weight;
  }

  System.out.println("Total Value: "+mvalue+"\nTotal Weight: "+mweight);
 }
}


Output: