I Have the following two classes and want to use Foo1
as keys in a HashMap
. Two Foo1
objects are equal if their Foo2
objects are equal, and Foo2
objects are equal if their byte arrays satisfy Arrays.equals()
.
I am not quite sure what to do for the hashCode()
method for Foo1
. Do I just need to sum up the hashcodes from each of its Foo2
objects or is this inefficient?
public class Foo1 {
Foo2[] foo2_array;
@Override
public boolean equals(Object Other) {
for (int i = 0; i < foo2_array.length; i++) {
if (!foo2_array[i].equals(other.foo2_array[i])
return false;
}
return true;
}
@Override
public int hashCode() {
// what to here?
}
}
public class Foo2 {
byte[] values;
@Override
public boolean equals(Object other) {
return Arrays.equals(values, other.values);
}
@Override
public int hashCode() {
return Arrays.hashCode(values);
}
}
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