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Bridje Inversion of Control API
/*
* Copyright 2015 Bridje Framework.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.bridje.ioc.impl;
import java.lang.reflect.Constructor;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.lang.reflect.WildcardType;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.concurrent.PriorityBlockingQueue;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.bridje.ioc.Priority;
/**
* Utility method for class and type handling.
*/
public class ClassUtils
{
private static final String JAVA_PACKAGE_PREFIX = "java.";
/**
* Logger for this class
*/
private static final Logger LOG = Logger.getLogger(ClassUtils.class.getName());
/**
* Gets the upper bounds Type for a WildcarType.
*
* ? extends SomeService = SomeService
* ? extends SomeService<String> = SomeService<String>
*
*
* @param service The wildcardType to inspect.
*
* @return The upper bounds Type of the WildcardType.
*/
public static Type typeOf(WildcardType service)
{
Type[] upperBounds = service.getUpperBounds();
if (upperBounds.length == 1)
{
return (upperBounds[0]);
}
else if (upperBounds.length == 0)
{
return Object.class;
}
return null;
}
/**
* Find the Type of an array, map or collection.
*
* SomeService[] = SomeService
* List<SomeService> = SomeService
* Map<Class, SomeService> = SomeService
*
*
* @param service The inner type of the multiple type passed.
*
* @return A type representing the inner type for the collection, array or
* map passed.
*/
public static Type multipleType(Type service)
{
if (isArray(service))
{
return arrayType(service);
}
else if (isCollection(service))
{
return collectionType(service);
}
else if (isMap(service))
{
return mapType(service);
}
return null;
}
/**
* Find the Type of an array.
*
* SomeService[] = SomeService
*
*
* @param service The inner type of the array type passed.
*
* @return A type representing the inner type for the array type passed.
*/
public static Type arrayType(Type service)
{
if (service instanceof GenericArrayType)
{
Type rawType = ((GenericArrayType) service).getGenericComponentType();
return rawType;
}
else if (service instanceof Class)
{
return ((Class) service).getComponentType();
}
return null;
}
/**
* Find the Type of collection.
*
* List<SomeService> = SomeService
* Set<SomeService> = SomeService
*
*
* @param service The inner type of the array type passed.
*
* @return A type representing the inner type for the collection type
* passed.
*/
public static Type collectionType(Type service)
{
if (service instanceof ParameterizedType)
{
Type[] args = ((ParameterizedType) service).getActualTypeArguments();
if (args.length == 1)
{
return args[0];
}
}
return null;
}
/**
* Find the Type of a map.
*
* Map<Class, SomeService> = SomeService
* HashMap<Class, SomeService> = SomeService
*
*
* @param service The inner type of the array type passed.
*
* @return A type representing the inner type for the map type passed.
*/
public static Type mapType(Type service)
{
if (service instanceof ParameterizedType)
{
Type[] args = ((ParameterizedType) service).getActualTypeArguments();
if (args.length == 2)
{
return args[1];
}
}
return null;
}
/**
* Returns the specified parameter from the ParameterizedType.
*
* @param service The ParameterizedType type to search the parameter.
* @param index The index of the actual parameter.
*
* @return If service is a ParameterizedType and the parameter is available
* it will return it, or null otherwise.
*/
public static Type parameterType(Type service, int index)
{
if (service instanceof ParameterizedType)
{
Type[] args = ((ParameterizedType) service).getActualTypeArguments();
if (index < args.length)
{
return args[index];
}
}
return null;
}
/**
* Determines whenever the passed type is an array, a java collection like
* List or Set, or a java Map.
*
* SomeService = false
* SomeService[] = true
* List<SomeService> = true
* Map<Class, SomeService> = true
* MyListImpl<SomeService> = false
* HashMap<Class, SomeService> = true
*
*
* @param service The type to inspect.
*
* @return true if the especified type is an array, a collection or map from
* java languaje.
*/
public static boolean isMultiple(Type service)
{
return isArray(service) || isCollection(service) || isMap(service);
}
/**
* Determines whenever the passed type is an array.
*
* SomeService = false
* SomeService[] = true
* List<SomeService> = false
* List<SomeService>[] = true
* Map<Class, SomeService> = false
* MyListImpl<SomeService> = false
* HashMap<Class, SomeService> = false
*
*
* @param service The type to inspect.
*
* @return true if the especified type is an array.
*/
public static boolean isArray(Type service)
{
if (service instanceof Class)
{
return ((Class) service).isArray();
}
else
{
return service instanceof GenericArrayType;
}
}
/**
* Determines whenever the passed type is a collection.
*
* SomeService = false
* SomeService[] = false
* List<SomeService> = true
* List<SomeService>[] = true
* Map<Class, SomeService> = false
* MyListImpl<SomeService> = false
* HashMap<Class, SomeService> = false
*
*
* @param service The type to inspect.
*
* @return true if the especified type is a List Set or other java
* collection except a map.
*/
public static boolean isCollection(Type service)
{
Class cls = rawClass(service);
if (cls == null || cls.isArray() || cls.getPackage() == null)
{
return false;
}
return isJavaPackage(cls.getPackage().getName())
&& Collection.class.isAssignableFrom(cls)
&& !Map.class.isAssignableFrom(cls);
}
/**
* Determines whenever the passed type is a map.
*
* SomeService = false
* SomeService[] = false
* List<SomeService> = false
* List<SomeService>[] = false
* Map<Class, SomeService> = true
* MyListImpl<SomeService> = false
* HashMap<Class, SomeService> = true
*
*
* @param service The type to inspect.
*
* @return true if the especified type is a java Map.
*/
public static boolean isMap(Type service)
{
Class cls = rawClass(service);
if (cls == null || cls.isArray() || cls.getPackage() == null)
{
return false;
}
return isJavaPackage(cls.getPackage().getName())
&& Map.class.isAssignableFrom(cls);
}
/**
* Gets the raw class for the especified Type.
*
* SomeService = SomeService
* SomeService[] = SomeService[]
* List<SomeService> = List
* List<SomeService>[] = List[]
* Map<Class, SomeService> = Map
* MyListImpl<SomeService> = MyListImpl
* HashMap<Class, SomeService> = HashMap
*
*
* @param service The type to take the raw class from.
*
* @return The raw class for the given type.
*/
public static Class rawClass(Type service)
{
if (service instanceof Class)
{
return ((Class) service);
}
else if (service instanceof ParameterizedType)
{
Type rawType = ((ParameterizedType) service).getRawType();
if (rawType instanceof Class)
{
return ((Class) rawType);
}
}
else if (service instanceof WildcardType)
{
Type wildCardType = typeOf((WildcardType) service);
return rawClass(wildCardType);
}
return null;
}
/**
* Gets a collection with all the classes of the objects from the especified
* collection.
*
* @param instances The objects to obtain it´s classes from.
*
* @return A Collection object with all the classes of the object´s in the
* collection passed.
*/
public static Collection> toClasses(Collection instances)
{
List> arrList = new ArrayList<>();
for (Object instance : instances)
{
arrList.add(instance.getClass());
}
return arrList;
}
/**
* Finds te priority value for a class, from it´s @Priority annotation if it
* haveit.
*
* @param cls The class to find it´s priority.
*
* @return The int value of the priority, by default the priority will be
* Integer.MAX_VALUE if not especified directly in the component.
*/
public static int findPriority(Class cls)
{
Priority a1 = cls.getAnnotation(Priority.class);
int v1 = Integer.MAX_VALUE;
if (a1 != null)
{
v1 = a1.value();
}
return v1;
}
/**
* Given a multiple type, (array, collection, or map) this method will
* return the appropied instance for it.
*
* SomeService = null
* SomeService[] = SomeService[]
* List<SomeService> = ArrayList
* List<SomeService>[] = List[]
* Map<Class, SomeService> = Map
* MyListImpl<SomeService> = null
* HashMap<Class, SomeService> = HashMap
*
*
* @param service The type of the array, collection or map.
* @param data The data to put on the result listing.
*
* @return The proper object for the especified type.
*/
public static Object createMultiple(Type service, Object[] data)
{
try
{
if (data != null)
{
if (ClassUtils.isCollection(service))
{
Class resultClass = rawClass(service);
return ClassUtils.createCollection(resultClass, data);
}
else if (ClassUtils.isMap(service))
{
Class resultClass = rawClass(service);
return ClassUtils.createCollection(resultClass, data);
}
else if (ClassUtils.isArray(service))
{
return data;
}
}
}
catch (InstantiationException | IllegalAccessException ex)
{
LOG.log(Level.SEVERE, ex.getMessage(), ex);
}
return null;
}
/**
* Given a collection type this method will return the appropied instance
* for it.
*
* SomeService = null
* SomeService[] = null
* List<SomeService> = ArrayList
* LinkedList<SomeService> = LinkedList
* List<SomeService>[] = null
* Map<Class, SomeService> = null
* MyListImpl<SomeService> = null
* HashMap<Class, SomeService> = null
*
*
* @param collectionCls The class for the collection.
* @param data The data for the collection.
*
* @return The collection.
*
* @throws InstantiationException if the collection cannot be instance.
* @throws IllegalAccessException security exception.
*/
public static Collection createCollection(Class collectionCls, Object[] data) throws InstantiationException, IllegalAccessException
{
Collection res = null;
Constructor construct = findConstructor(collectionCls);
if (construct != null && construct.isAccessible())
{
res = (Collection) collectionCls.newInstance();
}
else if (collectionCls.isAssignableFrom(ArrayList.class))
{
res = new ArrayList(data.length);
}
else if (collectionCls.isAssignableFrom(LinkedHashSet.class))
{
res = new LinkedHashSet(data.length);
}
else if (collectionCls.isAssignableFrom(PriorityBlockingQueue.class))
{
res = new PriorityBlockingQueue(data.length);
}
if (res != null)
{
res.addAll(Arrays.asList(data));
}
return res;
}
/**
* Given a map type this method will return the appropied instance for it.
*
* SomeService = null
* SomeService[] = null
* List<SomeService> = null
* List<SomeService>[] = null
* Map<Class, SomeService> = Map
* MyListImpl<SomeService> = null
* HashMap<Class, SomeService> = HashMapl
*
*
* @param mapCls The clss for the map.
* @param data The data for the map.
*
* @return The map.
*
* @throws InstantiationException if the collection cannot be instance.
* @throws IllegalAccessException security exception.
*/
public static Map createMap(Class mapCls, Object[] data) throws InstantiationException, IllegalAccessException
{
Map map = null;
Constructor construct = findConstructor(mapCls);
if (construct != null && construct.isAccessible())
{
map = (Map) mapCls.newInstance();
}
else if (mapCls.isAssignableFrom(LinkedHashMap.class))
{
map = new LinkedHashMap(data.length);
}
if (map != null)
{
for (Object cmp : data)
{
map.put(cmp.getClass(), cmp);
}
}
return map;
}
/**
* Finds the default constructor for the especified class.
*
* @param cls The class to find the constructor for.
*
* @return The default constructor for the class of null if none can be
* found.
*/
private static Constructor findConstructor(Class cls)
{
Constructor[] constructors = cls.getConstructors();
for (Constructor constructor : constructors)
{
if (constructor.getParameterCount() == 0)
{
return constructor;
}
}
return null;
}
/**
* Sorts a list of components by priority.
*
* @param value The list of classes to sort.
*/
public static void sort(List> value)
{
Collections.sort(value, (Class c1, Class c2)
->
{
int v1 = ClassUtils.findPriority(c1);
int v2 = ClassUtils.findPriority(c2);
return Integer.compare(v1, v2);
});
}
/**
* Determines whenever the especified type has a wildcard or TypeVariable
* declaration whiting.
*
* SomeService<T> = true
* SomeService<?> = true
* SomeService = false
* SomeService<String> = false
*
*
* @param type The type to inspect.
*
* @return true the especified type has a generic declaration, false
* otherwise.
*/
public static boolean hasGenericDeclaration(Type type)
{
if (type instanceof ParameterizedType)
{
ParameterizedType pType = (ParameterizedType) type;
Type[] types = pType.getActualTypeArguments();
for (Type t : types)
{
if (hasGenericDeclaration(t))
{
return true;
}
}
}
return type instanceof TypeVariable || type instanceof WildcardType;
}
private static boolean isJavaPackage(String name)
{
return name.startsWith(JAVA_PACKAGE_PREFIX);
}
}