Equals() example in Java

public final class Date implements Comparable<Date> {
    private final int month;
    private final int day;
    private final int year;
 
    public boolean equals(Object y) {
        if (y == this) {
            return true;
        }
 
        if (y == null) {
            return false;
        }
 
        if (y.getClass() != this.getClass()) {
            return false;
        }
 
        Date that = (Date) y;
        
        if (this.day != that.day) {
            return false;
        }
 
        if (this.month != that.month) {
            return false;
        }
 
        if (this.year != that.year) {
            return false;
        }
 
        return true;
    }
}