force subclasses to include constant in abstract java class

This will not work that way. I would define these as abstract functions:

protected abstract String objectName();
protected abstract String objectDef();

And in the subclass:

private static final String OBJECT_NAME = "awesome class";
private static final String OBJECT_DEF = "bla";

protected String objectName(){
    return OBJECT_NAME;
}

protected String objectDef(){
    return OBJECT_DEF;
}

The methods are not static, but I think this is the closest you can get to what you want.

You can force sub-class to define a method which can be a constant for that class.

protected abstract String objectName();
protected abstract String objectDef();

Note: if you have sub-class of your sub-classes, these might "forget" to override these methods.