Type1 接口注入

我們經常借助接口來將調用者與實現者分離。如:

public class ClassA {
PRivate InterfaceB clzB;
public init() {
Ojbect obj =
Class.forName(Config.BImplementation).newInstance();
clzB = (InterfaceB)obj;
}
……
}

public class DIByConstrUCtor
{
private final DataSource dataSource;
private final String message;
public DIByConstructor(DataSource ds, String msg)
{
this.dataSource = ds;
this.message = msg;
}
……
}