I have a problem with DI and lazy initialization.
Supose we have a code:

class IdObject {
Database db;
Memcache mc;
int id;
String data;

IdObject(int id, Database db, Memcache mc) {
this.db = db;
this.mc = mc;
this.id = id;
}

int load_data() {
this.data = mc.get(this.id);
if (this.data === null) {
this.data = db.get(this.id);
}
}
}

So using DI during creating IdObject we are creating both Database and Memcache objects, before we use load_data(), but moreover we create Database object even we need it, bacause in most cases mc.get() return data differentfrom null. So we have Database object and we have database connetction though we don’t need it.
I’m PHP developer and after each script execution the connection is close. One of the solutions is connect to database when we use get() methods, but we must implement this also in others methods. Is the better solution to this problem?
Thanks, and sorry for my poor English.