linkedhashmap in java

linkedhashmap in java

  March 27, 2017    

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Linked hash Map maintains order of entered data but hashmap does not.

uses , Application :

It works for LRU based apps like most recently open files ...

Example :


import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;

public class LinkedHashMapExec {
public static void main(String[] args) {
LinkedHashMap<Car, Owner> cars = new LinkedHashMap<Car, Owner>();

for(int i=0; i<10; i++){
cars.put("a+i","ower+i");
}

LinkedHashMapExec.mapIterator(cars);

System.out.println("HashMap=====");
HashMap<Car, Owner> hashMap = new HashMap<Car, Owner>();
hashMap.putAll(cars);

LinkedHashMapExec.mapIterator(hashMap);

System.out.println("Access Order===");
LinkedHashMap<Car, Owner> carsOrder = new LinkedHashMap<Car, Owner>(10, 2.1f, true);
carsOrder.putAll(cars);

LinkedHashMapExec.mapIterator(carsOrder);

System.out.println("After access===");
carsOrder.get(new Car("H-5"));
LinkedHashMapExec.mapIterator(carsOrder);
}

public static void mapIterator(Map<Car, Owner> map){
Iterator<Map.Entry<Car, Owner>> itr = map.entrySet().iterator();
while(itr.hasNext()){
Map.Entry<Car, Owner> entry = itr.next();
System.out.println(entry.getKey()+" Owner:"+entry.getValue());
}
}
}