AbstractMap.SimpleEntry<K, V> is used to maintain a key and a value entry. The value can be changed using the equals? method. This class facilitates the process of building custom map implementations.
equals(Object o) method of AbstractMap.SimpleEntry<K, V> used to compare the specified object passed as parameter with this entry for equality.The method returns true if the given object also contains a map entry and the two entries represent the same mapping.
Two entries e1 and e2 represent the same mapping if
(e1.getKey()==null ?
e2.getKey()==null :
e1.getKey().equals(e2.getKey()))
&&
(e1.getValue()==null ?
e2.getValue()==null :
e1.getValue().equals(e2.getValue()))
Syntax:
public V equals(Object o)
Parameters: This method accepts object to be compared for equality with this map entry.
Return value: This method true if the specified object is equal to this map entry.
Below programs illustrate equals(Object o) method:
Program 1:
// Java program to demonstrate// AbstractMap.SimpleEntry.equals() method import java.util.*; public class GFG { @SuppressWarnings({ "unchecked", "rawtypes" }) public static void main(String[] args) { // create two maps AbstractMap.SimpleEntry<Integer, Integer> map1 = new AbstractMap.SimpleEntry(0, 123); AbstractMap.SimpleEntry<Integer, Integer> map2 = new AbstractMap.SimpleEntry(0, 123); // compare both maps boolean answer = map1.equals(map2); // print result System.out.println("Map 1 is equal to Map2 -> " + answer); }} |
Map 1 is equal to Map2 -> true
Program 2:
// Java program to demonstrate// AbstractMap.SimpleEntry.equals() method import java.util.*; public class GFG { @SuppressWarnings({ "unchecked", "rawtypes" }) public static void main(String[] args) { // create two maps AbstractMap.SimpleEntry<String, String> map1 = new AbstractMap .SimpleEntry<String, String>("Captain:", "Dhoni"); AbstractMap.SimpleEntry<String, String> map2 = new AbstractMap .SimpleEntry<String, String>("Captain:", "Kohli"); // compare both maps boolean answer = map1.equals(map2); // print result System.out.println("Map 1 is equal to Map2 -> " + answer); }} |
Map 1 is equal to Map2 -> false
References: https://docs.oracle.com/javase/10/docs/api/java/util/AbstractMap.SimpleEntry.html##equals(java.lang.Object)
