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ComPonent thinking in Java
e AgeCalculator class has been modified to implement ComponentInterface
in addition to the AgeCalculatorIfce business interface that it implements.
ComponentInterface is just a marker interface (an interface that does not dictate
any operation to be implemented but is used for marking a class to be of a certain
type). e source code for ComponentInterface is defined in the Component
M o d e l.j a r library and is presented below:
package codabook.componentmodel;
public interface ComponentInterface {
}
e ComponentModel.jar library also hosts the ComponentRegistry, whose
source code is presented below:
package codabook.componentmodel;
import java.util.HashMap;
import java.util.Map;
public class ComponentRegistry {
static ...