「Spring MVC開発」DispatcherServletの使い方
Javaコード:
public interface HandlerAdapter {
public boolean supports(Object handler);
public void handle(Object handler);
}
public interface Controller {
}
public class HttpController implements Controller{
public void doHttpHandler(){
System.out.println(“http…");
}
}
public class SimpleController implements Controller{
public void doSimplerHandler(){
System.out.println(“simple…");
}
}
public class AnnotationController implements Controller{
public void doAnnotationHandler(){
System.out.println(“annotation…");
}
}
public class SimpleHandlerAdapter implements HandlerAdapter {
public void handle(Object handler) {
((SimpleController)handler).doSimplerHandler();
}
public boolean supports(Object handler) {
return (handler instanceof SimpleController);
}
}
public class HttpHandlerAdapter implements HandlerAdapter {
public void handle(Object handler) {
((HttpController)handler).doHttpHandler();
}
public boolean supports(Object handler) {
return (handler instanceof HttpController);
}
}
public class AnnotationHandlerAdapter implements HandlerAdapter {
public void handle(Object handler) {
((AnnotationController)handler).doAnnotationHandler();
}
public boolean supports(Object handler) {
return (handler instanceof AnnotationController);
}
}
//DispatcherServlet
import java.util.ArrayList;
import java.util.List;
public class DispatchServlet {
public static List<HandlerAdapter> handlerAdapters = new ArrayList<HandlerAdapter>();
public DispatchServlet(){
handlerAdapters.add(new AnnotationHandlerAdapter());
handlerAdapters.add(new HttpHandlerAdapter());
handlerAdapters.add(new SimpleHandlerAdapter());
}
public void doDispatch(){
SimpleController controller = new SimpleController();
HandlerAdapter adapter = getHandler(controller);
adapter.handle(controller);
}
public HandlerAdapter getHandler(Controller controller){
for(HandlerAdapter adapter: this.handlerAdapters){
if(adapter.supports(controller)){
return adapter;
}
}
return null;
}
public static void main(String[] args){
new DispatchServlet().doDispatch();
}
}