reflections

IgnorePolicy.java

package ch.schumm.security.pdp;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/**
 * Policies mit dieser Annotation werden vom PolicyDispatcher nicht geladen und damit auch nicht ausgewertet.
 * @author C709360
 * 
 */
@Retention(RetentionPolicy.RUNTIME)
public @interface IgnorePolicy {

}

ReflectionPolicyFinder.java

package ch.schumm.security.pdp;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

import org.reflections.Reflections;

import ch.schumm.security.policy.Policy;

public class ReflectionPolicyFinder {

    /**
     * Findet alle Policies im Packet ch.schumm.security.policy - ausser Policies mit der {@link IgnorePolicy}
     * Annotation, z.B. die Default-Policy.
     * @return
     */
    public static List<Policy> scanForPolicies() {
        Reflections reflections = new Reflections("ch.schumm.security.policy");

        Set<Class<? extends Policy>> policyTypes = reflections.getSubTypesOf(Policy.class);
        ArrayList<Policy> policiesReturn = new ArrayList<Policy>();

        for (Class<? extends Policy> policyType : policyTypes) {

            // if (policyType != DefaultPolicy.class) {
            if (!policyHasIgnoreAnnotation(policyType)) {
                try {
                    Policy policy = policyType.newInstance();
                    policiesReturn.add(policy);
                    System.out.println(policy);
                } catch (InstantiationException e) {
                    throw new PolicFinderException(e);
                } catch (IllegalAccessException e) {
                    throw new PolicFinderException(e);
                }
            }

        }
        return policiesReturn;
    }

    private static boolean policyHasIgnoreAnnotation(Class<? extends Policy> policyType) {
        boolean hasIgnoreAnotation = false;
        Annotation[] declaredAnnotations = policyType.getDeclaredAnnotations();
        for (Annotation annotation : declaredAnnotations) {
            if (annotation.annotationType() == IgnorePolicy.class) {
                hasIgnoreAnotation = true;
            }
        }
        return hasIgnoreAnotation;
    }

    public static void main(String[] args) {
        scanForPolicies();
    }

}