org.eclipse.mdm.nucleus/org.eclipse.mdm.businessobjects/src/main/java/org/eclipse/mdm/businessobjects/utils/ReflectUtil.java

/********************************************************************************
 * Copyright (c) 2015-2019 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/

package org.eclipse.mdm.businessobjects.utils;

import io.vavr.collection.HashMap;
import io.vavr.collection.Map;

/**
 * Utility class for method reflection
 * 
 * @author Johannes Stamm, Peak Solution GmbH Nuernberg
 *
 */
public class ReflectUtil {
	private static final Map<Class<?>, Class<?>> primitiveWrapperMap = HashMap.of(boolean.class, Boolean.class,
			byte.class, Byte.class, char.class, Character.class, double.class, Double.class, float.class, Float.class,
			int.class, Integer.class, long.class, Long.class, short.class, Short.class);

	public static boolean isPrimitiveWrapperOf(Class<?> targetClass, Class<?> primitive) {
		if (!primitive.isPrimitive()) {
			throw new IllegalArgumentException("First argument has to be primitive type");
		}
		return primitiveWrapperMap.get(primitive).get() == targetClass;
	}

	/**
	 * This function returns same value as to.isAssignableFrom(from), except for
	 * wrapper classes.
	 * 
	 * to.isAssignableFrom(from) returns false for wrapper class <-> primitive This
	 * function returns true in that case.
	 * 
	 * @param from class to assign from
	 * @param to   class to assign to
	 * @return true if assigning is possible (respecting auto boxing/unboxing) false
	 *         otherwise
	 */
	public static boolean isAssignableTo(Class<?> from, Class<?> to) {
		if (to.isAssignableFrom(from)) {
			return true;
		}
		if (from.isPrimitive()) {
			return isPrimitiveWrapperOf(to, from);
		}
		if (to.isPrimitive()) {
			return isPrimitiveWrapperOf(from, to);
		}
		return false;
	}

}