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POHashMap with override equals and hashCode not working
 

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    <p>Sorry ... about this silly/stupid question, guys:</p> <p>Why aren't <code>equals()</code> and <code>hashCode()</code> being applied?</p> <p>Currently they are only working as I expected for <code>HashSet</code>.</p> <p><strong>UPDATE</strong></p> <p>EVEN key value 5 is repeated but it doesn't call equals and hashCode.</p> <p>I want to apply it also on Value.</p> <p>As just like HashSet calls equal and hashCode in this example, why hashMap is not being called equals and hashCode even if for key.</p> <p><strong>UPDATE2 - ANSWER</strong></p> <p>HashMap's key(class->HashCode, equals) would be called. Thank you All. I was little bit confused on this. :)</p> <pre><code> public class Employee { int id; String name; int phone; public Employee(int id, String name, int phone) { this.id = id; this.name = name; this.phone = phone; } // Getter Setter @Override public boolean equals(Object obj) { if (obj == null) { return false; } if (getClass() != obj.getClass()) { return false; } final Employee other = (Employee) obj; System.out.println("Employee - equals" + other.getPhone()); if (this.id != other.id) { return false; } if ((this.name == null) ? (other.name != null) : !this.name.equals(other.name)) { return false; } if (this.phone != other.phone) { return false; } return true; } @Override public int hashCode() { System.out.println("Employee - hashCode" ); int hash = 3; hash = 67 * hash + this.id; hash = 67 * hash + (this.name != null ? this.name.hashCode() : 0); hash = 67 * hash + this.phone; return hash; } } ____________________________________________________________________________________ public class MapClass { public static void main(String[] args) { Map&lt;Integer,Employee&gt; map = new HashMap&lt;Integer,Employee&gt;(); map.put(1, new Employee(1, "emp", 981)); map.put(2, new Employee(2, "emp2", 982)); map.put(3, new Employee(3, "emp3", 983)); map.put(4, new Employee(4, "emp4", 984)); map.put(5, new Employee(4, "emp4", 984)); **//UPDATE** map.put(5, new Employee(4, "emp4", 984)); System.out.println("Finish Map" + map.size()); Set&lt;Employee&gt; set = new HashSet&lt;Employee&gt;(); set.add(new Employee(1, "emp", 981)); set.add(new Employee(2, "emp2", 982)); set.add(new Employee(2, "emp2", 982)); set.add(new Employee(3, "emp3", 983)); set.add(new Employee(4, "emp4", 984)); set.add(new Employee(4, "emp4", 984)); System.out.println(set.size()); } } </code></pre> <p>OUTPUT IS </p> <pre><code>Finish Map5 Employee - hashCode Employee - hashCode Employee - hashCode Employee - equals982 Employee - equals982 Employee - hashCode Employee - hashCode Employee - hashCode Employee - equals984 Employee - equals984 4 </code></pre>
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    1. USJason
    1. USRavi Parekh
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    1. COWhat is the problem exactly? Remember that in HashMap, the keys is hashed, not the value
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      1. USGuillaume Polet
    2. COhow would i call hascode & equals for hashMap
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      1. USRavi Parekh
    3. COThe Map calls the equals and hashCode methods, and it is doing that -- for the Integer key! If you want the Map to check Employee hashCode and/or equals then Employee must be the Key not the Value.
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      1. USHovercraft Full Of Eels
 

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