Why this .equals() code example returns “false”? [duplicate]

Answer 1

The equals method by default says "Is this the same object in memory?" unless you override it.

You didn't override it.

The behavior didn't change.

You'll want to add a new method like this

public boolean equals(Object o) {
    if(o instanceof Dog) {
        Dog d = (Dog)(o);
        Dog t = this;
        return t.height == d.height && t.weight == d.weight && t.name.equals(d.name);
    }
    return false;
}

Stephan brings up a good point - never, ever, ever implment equals without hashCode. Always use the same fields in both.

public int hashCode() {
    int hash = name.hashCode();
    hash = hash * 31 + weight;
    hash = hash * 31 + height;
    return hash;
}