src/share/classes/java/beans/ReflectionUtils.java

/*
 * Copyright (c) 2003, 2009, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package java.beans;

import java.lang.reflect.Field;

/**
 * A utility class for reflectively finding methods, constuctors and fields
 * using reflection.
 */
class ReflectionUtils {

    public static boolean isPrimitive(Class type) {
        return primitiveTypeFor(type) != null;
    }

    public static Class primitiveTypeFor(Class wrapper) {
        if (wrapper == Boolean.class) return Boolean.TYPE;
        if (wrapper == Byte.class) return Byte.TYPE;
        if (wrapper == Character.class) return Character.TYPE;
        if (wrapper == Short.class) return Short.TYPE;
        if (wrapper == Integer.class) return Integer.TYPE;
        if (wrapper == Long.class) return Long.TYPE;
        if (wrapper == Float.class) return Float.TYPE;
        if (wrapper == Double.class) return Double.TYPE;
        if (wrapper == Void.class) return Void.TYPE;
        return null;
    }

    /**
     * Returns the value of a private field.
     *
     * @param instance object instance
     * @param cls class
     * @param name name of the field
     * @param el an exception listener to handle exceptions; or null
     * @return value of the field; null if not found or an error is encountered
     */
    public static Object getPrivateField(Object instance, Class cls,
                                         String name, ExceptionListener el) {
        try {
            Field f = cls.getDeclaredField(name);
            f.setAccessible(true);
            return f.get(instance);
        }
        catch (Exception e) {
            if (el != null) {
                el.exceptionThrown(e);
            }
        }
        return null;
    }
}