Returns true if type is implementing Map
// $Id: ReflectionHelper.java 16271 2009-04-07 20:20:12Z hardy.ferentschik $
/*
* JBoss, Home of Professional Open Source
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* 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.
*/
import java.beans.Introspector;
import java.lang.annotation.Annotation;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.WildcardType;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* Some reflection utility methods.
*
* @author Hardy Ferentschik
*/
public class ReflectionHelper {
/**
* @param type the type to check.
*
* @return Returns <code>true</code> if <code>type</code> is implementing <code>Map</code>, <code>false</code> otherwise.
*/
public static boolean isMap(Type type) {
if ( type instanceof Class && isMapClass( ( Class ) type ) ) {
return true;
}
if ( type instanceof ParameterizedType ) {
return isMap( ( ( ParameterizedType ) type ).getRawType() );
}
if ( type instanceof WildcardType ) {
Type[] upperBounds = ( ( WildcardType ) type ).getUpperBounds();
return upperBounds.length != 0 && isMap( upperBounds[0] );
}
return false;
}
/**
* Checks whether the specified class parameter is an instance of a collection class.
*
* @param clazz <code>Class</code> to check.
*
* @return <code>true</code> is <code>clazz</code> is instance of a collection class, <code>false</code> otherwise.
*/
private static boolean isMapClass(Class<?> clazz) {
List<Class<?>> classes = new ArrayList<Class<?>>();
computeClassHierarchy( clazz, classes );
return classes.contains( Map.class );
}
/**
* Get all superclasses and interfaces recursively.
*
* @param clazz The class to start the search with.
* @param classes List of classes to which to add all found super classes and interfaces.
*/
private static void computeClassHierarchy(Class<?> clazz, List<Class<?>> classes) {
for ( Class current = clazz; current != null; current = current.getSuperclass() ) {
if ( classes.contains( current ) ) {
return;
}
classes.add( current );
for ( Class currentInterface : current.getInterfaces() ) {
computeClassHierarchy( currentInterface, classes );
}
}
}
}
Related examples in the same category
