Java Program to Implement LinkedHashMap API

// Java program demonstrate LinkedHashMap API import java.util.Collection; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedHashMap; import java.util.Map; import java.util.Map.Entry; import java.util.Set; class LinkedHashMapImplementation<K, V> {  private LinkedHashMap<K, V> map;  // Constructor creates a new LinkedHashMap  public LinkedHashMapImplementation()  {  map = new LinkedHashMap<K, V>();  }  // Constructor creates a new empty linkedhash map  // according to the given map  public LinkedHashMapImplementation(  Map<? extends K, ? extends V> map1)  {  map = new LinkedHashMap<K, V>(map1);  }  // Delete all the key-value pair  public void clear() { map.clear(); }  // Returns a shallow copy of the LinkedHashMap instance  public Object clone() { return map.clone(); }  // Returns true if the map contains the specified key  public boolean containsKey(Object key)  {  return map.containsKey(key);  }  // Returns true if map contains specified value  public boolean containsValue(Object val)  {  return map.containsValue(val);  }  // Returns a Set view of the mappings  public Set<Map.Entry<K, V> > entrySet()  {  return map.entrySet();  }  // Returns the value to which the specified key is  // mapped, returns null if map does not contains given  // key  public V get(Object key) { return map.get(key); }  // Returns a Set view of the keys  public Set<K> keySet() { return map.keySet(); }  // Associates the specified value with the specified key  // in the map  public V put(K key, V val) { return map.put(key, val); }  // Copies all of the mappings from the specified map to  // the map  public void putAll(Map<? extends K, ? extends V> map1)  {  map.putAll(map1);  }  // Removes the mapping for the key from the  // LinkedHashMap if present  public V remove(Object key) { return map.remove(key); }  // Returns the size of the map  public int size() { return map.size(); }  // Returns a Collection view of the values  public Collection<V> values() { return map.values(); } } public class GFG {  public static void main(String[] arg)  {  LinkedHashMapImplementation<String, Integer> student  = new LinkedHashMapImplementation<>();  // Add elements to the LinkedHashMap  student.put("Anuj", 500);  student.put("Ashok", 460);  student.put("Aakansha", 495);  // Print the size of the LinkedHashMap  System.out.println("Size of the LinkedHashMap: "  + student.size());  System.out.println();  System.out.println(  "The key value pairs of LinkedHashMap:");  // Print the key value pairs of LinkedHashMap  for (Map.Entry<String, Integer> entry :  student.entrySet()) {  System.out.println(entry.getKey() + " : "  + entry.getValue());  }    System.out.println();  // Print LinkedHashMap contains key Aakansha or not  System.out.println(  "LinkedHashMap contains Aakansha: "  + student.containsKey("Aakansha"));  System.out.println();  // Print LinkedHashMap contains value 450 or not  System.out.println("LinkedHashMap contains 450: "  + student.containsValue(450));  System.out.println();  // Deletes all the entry  student.clear();  System.out.println("Size of the LinkedHashMap: "  + student.size());  } }