import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;
-import static org.opendaylight.yangtools.concepts.util.ClassLoaderUtils.withClassLoader;
+import com.google.common.base.Optional;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.ImmutableSet.Builder;
+import com.google.common.collect.Sets;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
+import java.net.URI;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
import java.util.ServiceLoader;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
-
-import org.opendaylight.yangtools.concepts.util.ClassLoaderUtils;
+import org.opendaylight.yangtools.util.ClassLoaderUtils;
import org.opendaylight.yangtools.yang.binding.Augmentable;
import org.opendaylight.yangtools.yang.binding.Augmentation;
import org.opendaylight.yangtools.yang.binding.BaseIdentity;
import org.opendaylight.yangtools.yang.binding.YangModelBindingProvider;
import org.opendaylight.yangtools.yang.binding.YangModuleInfo;
import org.opendaylight.yangtools.yang.common.QName;
-
+import org.opendaylight.yangtools.yang.common.QNameModule;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-import com.google.common.base.Optional;
-import com.google.common.cache.CacheBuilder;
-import com.google.common.cache.CacheLoader;
-import com.google.common.cache.LoadingCache;
-import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.ImmutableSet.Builder;
-
public class BindingReflections {
private static final long EXPIRATION_TIME = 60;
.expireAfterAccess(EXPIRATION_TIME, TimeUnit.SECONDS) //
.build(new ClassToQNameLoader());
+ private BindingReflections() {
+ throw new UnsupportedOperationException("Utility class.");
+ }
+
/**
+ * Find augmentation target class from concrete Augmentation class
+ *
+ * This method uses first generic argument of implemented
+ * {@link Augmentation} interface.
*
* @param augmentation
* {@link Augmentation} subclass for which we want to determine
}
/**
+ * Find data hierarchy parent from concrete Data class
*
- * @param augmentation
- * {@link Augmentation} subclass for which we want to determine
- * augmentation target.
- * @return Augmentation target - class which augmentation provides
- * additional extensions.
+ * This method uses first generic argument of implemented {@link ChildOf}
+ * interface.
+ *
+ * @param childClass
+ * child class for which we want to find the parent class.
+ * @return Parent class, e.g. class of which the childClass is ChildOf.
*/
public static Class<?> findHierarchicalParent(final Class<? extends ChildOf<?>> childClass) {
return ClassLoaderUtils.findFirstGenericArgument(childClass, ChildOf.class);
}
/**
+ * Find data hierarchy parent from concrete Data class
*
- * @param augmentation
- * {@link Augmentation} subclass for which we want to determine
- * augmentation target.
- * @return Augmentation target - class which augmentation provides
- * additional extensions.
+ * This method is shorthand which gets DataObject class by invoking
+ * {@link DataObject#getImplementedInterface()} and uses
+ * {@link #findHierarchicalParent(Class)}.
+ *
+ * @param child
+ * Child object for which the parent needs to be located.
+ * @return Parent class, or null if a parent is not found.
*/
- public static Class<?> findHierarchicalParent(final DataObject childClass) {
- if (childClass instanceof ChildOf) {
- return ClassLoaderUtils.findFirstGenericArgument(childClass.getImplementedInterface(), ChildOf.class);
+ public static Class<?> findHierarchicalParent(final DataObject child) {
+ if (child instanceof ChildOf) {
+ return ClassLoaderUtils.findFirstGenericArgument(child.getImplementedInterface(), ChildOf.class);
}
return null;
}
* Returns a QName associated to supplied type
*
* @param dataType
- * @return QName associated to supplied dataType. If dataType is Augmentation
- * method does not return canonical QName, but QName with correct namespace
- * revision, but virtual local name, since augmentations do not have name.
+ * @return QName associated to supplied dataType. If dataType is
+ * Augmentation method does not return canonical QName, but QName
+ * with correct namespace revision, but virtual local name, since
+ * augmentations do not have name.
+ *
+ * May return null if QName is not present.
*/
public static final QName findQName(final Class<?> dataType) {
return classToQName.getUnchecked(dataType).orNull();
}
- private static class ClassToQNameLoader extends CacheLoader<Class<?>, Optional<QName>> {
-
- @Override
- public Optional<QName> load(final Class<?> key) throws Exception {
- try {
- Field field = key.getField(BindingMapping.QNAME_STATIC_FIELD_NAME);
- Object obj = field.get(null);
- if (obj instanceof QName) {
- return Optional.of((QName) obj);
- }
- } catch (NoSuchFieldException e) {
- if(Augmentation.class.isAssignableFrom(key)) {
- YangModuleInfo moduleInfo = getModuleInfo(key);
- return Optional.of(QName.create(moduleInfo.getNamespace(), moduleInfo.getRevision(), moduleInfo.getName()));
- }
- } catch (SecurityException | IllegalArgumentException | IllegalAccessException e) {
- // NOOP
- }
- return Optional.absent();
- }
- }
-
+ /**
+ * Checks if method is RPC invocation
+ *
+ *
+ *
+ * @param possibleMethod
+ * Method to check
+ * @return true if method is RPC invocation, false otherwise.
+ */
public static boolean isRpcMethod(final Method possibleMethod) {
return possibleMethod != null && RpcService.class.isAssignableFrom(possibleMethod.getDeclaringClass())
&& Future.class.isAssignableFrom(possibleMethod.getReturnType())
&& possibleMethod.getParameterTypes().length <= 1;
}
+ /**
+ *
+ * Extracts Output class for RPC method
+ *
+ * @param targetMethod
+ * method to scan
+ * @return Optional.absent() if result type could not be get, or return type
+ * is Void.
+ */
@SuppressWarnings("rawtypes")
public static Optional<Class<?>> resolveRpcOutputClass(final Method targetMethod) {
checkState(isRpcMethod(targetMethod), "Supplied method is not Rpc invocation method");
return Optional.absent();
}
+ /**
+ *
+ * Extracts input class for RPC method
+ *
+ * @param targetMethod
+ * method to scan
+ * @return Optional.absent() if rpc has no input, Rpc input type otherwise.
+ */
@SuppressWarnings("unchecked")
public static Optional<Class<? extends DataContainer>> resolveRpcInputClass(final Method targetMethod) {
@SuppressWarnings("rawtypes")
return findQName(context);
}
+ /**
+ *
+ * Checks if class is child of augmentation.
+ *
+ *
+ * @param clazz
+ * @return
+ */
public static boolean isAugmentationChild(final Class<?> clazz) {
// FIXME: Current resolver could be still confused when
// child node was added by grouping
return !clazzModelPackage.equals(parentModelPackage);
}
+ /**
+ * Returns root package name for suplied package.
+ *
+ * @param pkg
+ * Package for which find model root package.
+ * @return Package of model root.
+ */
public static String getModelRootPackageName(final Package pkg) {
return getModelRootPackageName(pkg.getName());
}
+ /**
+ * Returns root package name for supplied package name.
+ *
+ * @param name
+ * Package for which find model root package.
+ * @return Package of model root.
+ */
public static String getModelRootPackageName(final String name) {
checkArgument(name != null, "Package name should not be null.");
checkArgument(name.startsWith(BindingMapping.PACKAGE_PREFIX), "Package name not starting with %s, is: %s",
BindingMapping.PACKAGE_PREFIX, name);
Matcher match = ROOT_PACKAGE_PATTERN.matcher(name);
- checkArgument(match.find(),"Package name '%s' does not match required pattern '%s'",name,ROOT_PACKAGE_PATTERN_STRING);
+ checkArgument(match.find(), "Package name '%s' does not match required pattern '%s'", name,
+ ROOT_PACKAGE_PATTERN_STRING);
return match.group(0);
}
+ public static final QNameModule getQNameModule(Class<?> clz) {
+ if(DataContainer.class.isAssignableFrom(clz) || BaseIdentity.class.isAssignableFrom(clz)) {
+ return findQName(clz).getModule();
+ }
+ try {
+ YangModuleInfo modInfo = BindingReflections.getModuleInfo(clz);
+ return getQNameModule(modInfo);
+ } catch (Exception e) {
+ throw new IllegalStateException("Unable to get QName of defining model.", e);
+ }
+ }
+
+ public static final QNameModule getQNameModule(YangModuleInfo modInfo) {
+ return QNameModule.create(URI.create(modInfo.getNamespace()), QName.parseRevision(modInfo.getRevision()));
+ }
+
+ /**
+ *
+ * Returns instance of {@link YangModuleInfo} of declaring model for
+ * specific class.
+ *
+ * @param cls
+ * @return Instance of {@link YangModuleInfo} associated with model, from
+ * which this class was derived.
+ * @throws Exception
+ */
public static YangModuleInfo getModuleInfo(final Class<?> cls) throws Exception {
checkArgument(cls != null);
String packageName = getModelRootPackageName(cls.getPackage());
final String potentialClassName = getModuleInfoClassName(packageName);
- return withClassLoader(cls.getClassLoader(), new Callable<YangModuleInfo>() {
-
+ return ClassLoaderUtils.withClassLoader(cls.getClassLoader(), new Callable<YangModuleInfo>() {
@Override
- public YangModuleInfo call() throws ClassNotFoundException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException {
+ public YangModuleInfo call() throws ClassNotFoundException, IllegalAccessException,
+ IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException {
Class<?> moduleInfoClass = Thread.currentThread().getContextClassLoader().loadClass(potentialClassName);
return (YangModuleInfo) moduleInfoClass.getMethod("getInstance").invoke(null);
}
return packageName + "." + BindingMapping.MODULE_INFO_CLASS_NAME;
}
+ /**
+ *
+ * Check if supplied class is derived from YANG model.
+ *
+ * @param cls
+ * Class to check
+ * @return true if class is derived from YANG model.
+ */
public static boolean isBindingClass(final Class<?> cls) {
if (DataContainer.class.isAssignableFrom(cls) || Augmentation.class.isAssignableFrom(cls)) {
return true;
return (cls.getName().startsWith(BindingMapping.PACKAGE_PREFIX));
}
+ /**
+ *
+ * Checks if supplied method is callback for notifications.
+ *
+ * @param method
+ * @return true if method is notification callback.
+ */
public static boolean isNotificationCallback(final Method method) {
checkArgument(method != null);
if (method.getName().startsWith("on") && method.getParameterTypes().length == 1) {
return false;
}
+ /**
+ *
+ * Checks is supplied class is Notification.
+ *
+ * @param potentialNotification
+ * @return
+ */
public static boolean isNotification(final Class<?> potentialNotification) {
- checkArgument(potentialNotification != null);
+ checkArgument(potentialNotification != null, "potentialNotification must not be null.");
return Notification.class.isAssignableFrom(potentialNotification);
}
+ /**
+ *
+ * Loads {@link YangModuleInfo} infos available on current classloader.
+ *
+ * This method is shorthand for {@link #loadModuleInfos(ClassLoader)} with
+ * {@link Thread#getContextClassLoader()} for current thread.
+ *
+ * @return Set of {@link YangModuleInfo} available for current classloader.
+ */
public static ImmutableSet<YangModuleInfo> loadModuleInfos() {
return loadModuleInfos(Thread.currentThread().getContextClassLoader());
}
+ /**
+ *
+ * Loads {@link YangModuleInfo} infos available on supplied classloader.
+ *
+ * {@link YangModuleInfo} are discovered using {@link ServiceLoader} for
+ * {@link YangModelBindingProvider}. {@link YangModelBindingProvider} are
+ * simple classes which holds only pointers to actual instance
+ * {@link YangModuleInfo}.
+ *
+ * When {@link YangModuleInfo} is available, all dependencies are
+ * recursivelly collected into returning set by collecting results of
+ * {@link YangModuleInfo#getImportedModules()}.
+ *
+ *
+ * @param loader
+ * Classloader for which {@link YangModuleInfo} should be
+ * retrieved.
+ * @return Set of {@link YangModuleInfo} available for supplied classloader.
+ */
public static ImmutableSet<YangModuleInfo> loadModuleInfos(final ClassLoader loader) {
- Builder<YangModuleInfo> moduleInfoSet = ImmutableSet.<YangModuleInfo>builder();
- ServiceLoader<YangModelBindingProvider> serviceLoader = ServiceLoader.load(YangModelBindingProvider.class, loader);
- for(YangModelBindingProvider bindingProvider : serviceLoader) {
+ Builder<YangModuleInfo> moduleInfoSet = ImmutableSet.<YangModuleInfo> builder();
+ ServiceLoader<YangModelBindingProvider> serviceLoader = ServiceLoader.load(YangModelBindingProvider.class,
+ loader);
+ for (YangModelBindingProvider bindingProvider : serviceLoader) {
YangModuleInfo moduleInfo = bindingProvider.getModuleInfo();
- checkState(moduleInfo != null, "Module Info for %s is not available.",bindingProvider.getClass());
- collectYangModuleInfo(bindingProvider.getModuleInfo(),moduleInfoSet);
+ checkState(moduleInfo != null, "Module Info for %s is not available.", bindingProvider.getClass());
+ collectYangModuleInfo(bindingProvider.getModuleInfo(), moduleInfoSet);
}
- return moduleInfoSet.build();
+ return moduleInfoSet.build();
}
- private static void collectYangModuleInfo(final YangModuleInfo moduleInfo, final Builder<YangModuleInfo> moduleInfoSet) {
+ private static void collectYangModuleInfo(final YangModuleInfo moduleInfo,
+ final Builder<YangModuleInfo> moduleInfoSet) {
moduleInfoSet.add(moduleInfo);
- for(YangModuleInfo dependency : moduleInfo.getImportedModules()) {
+ for (YangModuleInfo dependency : moduleInfo.getImportedModules()) {
collectYangModuleInfo(dependency, moduleInfoSet);
}
}
+ /**
+ *
+ * Checks if supplied class represents RPC Input / RPC Output.
+ *
+ * @param targetType
+ * Class to be checked
+ * @return true if class represents RPC Input or RPC Output class.
+ */
public static boolean isRpcType(final Class<? extends DataObject> targetType) {
- return DataContainer.class.isAssignableFrom(targetType) //
+ return DataContainer.class.isAssignableFrom(targetType) //
&& !ChildOf.class.isAssignableFrom(targetType) //
&& !Notification.class.isAssignableFrom(targetType) //
&& (targetType.getName().endsWith("Input") || targetType.getName().endsWith("Output"));
}
+ /**
+ *
+ * Scans supplied class and returns an iterable of all data children
+ * classes.
+ *
+ * @param type
+ * YANG Modeled Entity derived from DataContainer
+ * @return Iterable of all data children, which have YANG modeled entity
+ */
+ @SuppressWarnings("unchecked")
+ public static Iterable<Class<? extends DataObject>> getChildrenClasses(final Class<? extends DataContainer> type) {
+ checkArgument(type != null, "Target type must not be null");
+ checkArgument(DataContainer.class.isAssignableFrom(type), "Supplied type must be derived from DataContainer");
+ List<Class<? extends DataObject>> ret = new LinkedList<>();
+ for (Method method : type.getMethods()) {
+ Optional<Class<? extends DataContainer>> entity = getYangModeledReturnType(method);
+ if (entity.isPresent()) {
+ ret.add((Class<? extends DataObject>) entity.get());
+ }
+ }
+ return ret;
+ }
+
+ /**
+ *
+ * Scans supplied class and returns an iterable of all data children
+ * classes.
+ *
+ * @param type
+ * YANG Modeled Entity derived from DataContainer
+ * @return Iterable of all data children, which have YANG modeled entity
+ */
+ public static Map<Class<?>, Method> getChildrenClassToMethod(final Class<?> type) {
+ checkArgument(type != null, "Target type must not be null");
+ checkArgument(DataContainer.class.isAssignableFrom(type), "Supplied type must be derived from DataContainer");
+ Map<Class<?>, Method> ret = new HashMap<>();
+ for (Method method : type.getMethods()) {
+ Optional<Class<? extends DataContainer>> entity = getYangModeledReturnType(method);
+ if (entity.isPresent()) {
+ ret.put(entity.get(), method);
+ }
+ }
+ return ret;
+ }
+
+ @SuppressWarnings("unchecked")
+ private static Optional<Class<? extends DataContainer>> getYangModeledReturnType(final Method method) {
+ if (method.getName().equals("getClass") || !method.getName().startsWith("get")
+ || method.getParameterTypes().length > 0) {
+ return Optional.absent();
+ }
+
+ @SuppressWarnings("rawtypes")
+ Class returnType = method.getReturnType();
+ if (DataContainer.class.isAssignableFrom(returnType)) {
+ return Optional.<Class<? extends DataContainer>> of(returnType);
+ } else if (List.class.isAssignableFrom(returnType)) {
+ try {
+ return ClassLoaderUtils.withClassLoader(method.getDeclaringClass().getClassLoader(),
+ new Callable<Optional<Class<? extends DataContainer>>>() {
+ @SuppressWarnings("rawtypes")
+ @Override
+ public Optional<Class<? extends DataContainer>> call() {
+ Type listResult = ClassLoaderUtils.getFirstGenericParameter(method
+ .getGenericReturnType());
+ if (listResult instanceof Class
+ && DataContainer.class.isAssignableFrom((Class) listResult)) {
+ return Optional.<Class<? extends DataContainer>> of((Class) listResult);
+ }
+ return Optional.absent();
+ }
+
+ });
+ } catch (Exception e) {
+ /*
+ *
+ * It is safe to log this this exception on debug, since this
+ * method should not fail. Only failures are possible if the
+ * runtime / backing.
+ */
+ LOG.debug("Unable to find YANG modeled return type for {}", method, e);
+ }
+ }
+ return Optional.absent();
+ }
+
+ private static class ClassToQNameLoader extends CacheLoader<Class<?>, Optional<QName>> {
+
+ @Override
+ public Optional<QName> load(final Class<?> key) throws Exception {
+ return resolveQNameNoCache(key);
+ }
+ }
+
+ /**
+ *
+ * Tries to resolve QName for supplied class.
+ *
+ * Looks up for static field with name from constant
+ * {@link BindingMapping#QNAME_STATIC_FIELD_NAME} and returns value if
+ * present.
+ *
+ * If field is not present uses {@link #computeQName(Class)} to compute
+ * QName for missing types.
+ *
+ * @param key
+ * @return
+ */
+ private static Optional<QName> resolveQNameNoCache(final Class<?> key) {
+ try {
+ Field field = key.getField(BindingMapping.QNAME_STATIC_FIELD_NAME);
+ Object obj = field.get(null);
+ if (obj instanceof QName) {
+ return Optional.of((QName) obj);
+ }
+
+ } catch (NoSuchFieldException e) {
+ return Optional.of(computeQName(key));
+
+ } catch (SecurityException | IllegalArgumentException | IllegalAccessException e) {
+ /*
+ *
+ * It is safe to log this this exception on debug, since this method
+ * should not fail. Only failures are possible if the runtime /
+ * backing.
+ */
+ LOG.debug("Unexpected exception during extracting QName for {}", key, e);
+ }
+ return Optional.absent();
+ }
+
+ /**
+ * Computes QName for supplied class
+ *
+ * Namespace and revision are same as {@link YangModuleInfo} associated with
+ * supplied class.
+ * <p>
+ * If class is
+ * <ul>
+ * <li>rpc input: local name is "input".
+ * <li>rpc output: local name is "output".
+ * <li>augmentation: local name is "module name".
+ * </ul>
+ *
+ * There is also fallback, if it is not possible to compute QName using
+ * following algorithm returns module QName.
+ *
+ * FIXME: Extend this algorithm to also provide QName for YANG modeled
+ * simple types.
+ *
+ * @throws IllegalStateException
+ * If YangModuleInfo could not be resolved
+ * @throws IllegalArgumentException
+ * If supplied class was not derived from YANG model.
+ *
+ */
+ @SuppressWarnings({ "rawtypes", "unchecked" })
+ private static QName computeQName(final Class key) {
+ if (isBindingClass(key)) {
+ YangModuleInfo moduleInfo;
+ try {
+ moduleInfo = getModuleInfo(key);
+ } catch (Exception e) {
+ throw new IllegalStateException("Unable to get QName for " + key + ". YangModuleInfo was not found.", e);
+ }
+ final QName module = getModuleQName(moduleInfo);
+ if (Augmentation.class.isAssignableFrom(key)) {
+ return module;
+ } else if (isRpcType(key)) {
+ final String className = key.getSimpleName();
+ if (className.endsWith(BindingMapping.RPC_OUTPUT_SUFFIX)) {
+ return QName.create(module, "output");
+ } else {
+ return QName.create(module, "input");
+ }
+ }
+ /*
+ * Fallback for Binding types which fo not have QNAME field
+ */
+ return module;
+ } else {
+ throw new IllegalArgumentException("Supplied class " + key + "is not derived from YANG.");
+ }
+ }
+
+ /**
+ * Given a {@link YangModuleInfo}, create a QName representing it. The QName
+ * is formed by reusing the module's namespace and revision using the
+ * module's name as the QName's local name.
+ *
+ * @param moduleInfo
+ * module information
+ * @return QName representing the module
+ */
+ public static QName getModuleQName(final YangModuleInfo moduleInfo) {
+ checkArgument(moduleInfo != null, "moduleInfo must not be null.");
+ return QName.create(moduleInfo.getNamespace(), moduleInfo.getRevision(), moduleInfo.getName());
+ }
+
+ /**
+ * Extracts augmentation from Binding DTO field using reflection
+ *
+ * @param input
+ * Instance of DataObject which is augmentable and may contain
+ * augmentation
+ * @return Map of augmentations if read was successful, otherwise empty map.
+ */
+ public static Map<Class<? extends Augmentation<?>>, Augmentation<?>> getAugmentations(final Augmentable<?> input) {
+ return AugmentationFieldGetter.getGetter(input.getClass()).getAugmentations(input);
+ }
+
+ /**
+ *
+ * Determines if two augmentation classes or case classes represents same
+ * data.
+ * <p>
+ * Two augmentations or cases could be substituted only if and if:
+ * <ul>
+ * <li>Both implements same interfaces</li>
+ * <li>Both have same children</li>
+ * <li>If augmentations: Both have same augmentation target class. Target
+ * class was generated for data node in grouping.</li>
+ * <li>If cases: Both are from same choice. Choice class was generated for
+ * data node in grouping.</li>
+ * </ul>
+ * <p>
+ * <b>Explanation:</b> Binding Specification reuses classes generated for
+ * groupings as part of normal data tree, this classes from grouping could
+ * be used at various locations and user may not be aware of it and may use
+ * incorrect case or augmentation in particular subtree (via copy
+ * constructors, etc).
+ *
+ * @param potential
+ * Class which is potential substition
+ * @param target
+ * Class which should be used at particular subtree
+ * @return true if and only if classes represents same data.
+ */
+ @SuppressWarnings({ "rawtypes", "unchecked" })
+ public static boolean isSubstitutionFor(final Class potential, final Class target) {
+ HashSet<Class> subImplemented = Sets.newHashSet(potential.getInterfaces());
+ HashSet<Class> targetImplemented = Sets.newHashSet(target.getInterfaces());
+ if (!subImplemented.equals(targetImplemented)) {
+ return false;
+ }
+ if (Augmentation.class.isAssignableFrom(potential)
+ && !BindingReflections.findAugmentationTarget(potential).equals(
+ BindingReflections.findAugmentationTarget(target))) {
+ return false;
+ }
+ for (Method potentialMethod : potential.getMethods()) {
+ try {
+ Method targetMethod = target.getMethod(potentialMethod.getName(), potentialMethod.getParameterTypes());
+ if (!potentialMethod.getReturnType().equals(targetMethod.getReturnType())) {
+ return false;
+ }
+ } catch (NoSuchMethodException e) {
+ // Counterpart method is missing, so classes could not be
+ // substituted.
+ return false;
+ } catch (SecurityException e) {
+ throw new IllegalStateException("Could not compare methods", e);
+ }
+ }
+ return true;
+ }
}
Code Review / mdsal.git / blobdiff