equals() and hashCode()
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public class Main {
public static void main(String[] args) {
ABC a = new ABC(123);
ABC b = a;
ABC c = new ABC(123);
System.out.println("==:");
System.out.println(a == b);
System.out.println(a == c);
System.out.println("\nequals():");
System.out.println(a.equals(b));
System.out.println(a.equals(c));
System.out.println("\nhashCode():");
System.out.println(a.hashCode());
System.out.println(b.hashCode());
System.out.println(c.hashCode());
}
}
class ABC {
public int i;
public ABC(int i) {
this.i = i;
}
/*
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
ABC abc = (ABC) o;
return i == abc.i;
}
public int hashCode() {
return i;
}
*/
}
Java
INFO