FactoryHelper.java

/*
 * Copyright 2007 The Fornax Project Team, including the original 
 * author or authors.
 * 
 * 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.sculptor.framework.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Utility class for creating Objects from properties (Strings).
 * 
 * @author Patrik Nordwall
 */
public class FactoryHelper {

    private static final Logger LOG = LoggerFactory.getLogger(FactoryHelper.class);

    private FactoryHelper() {
    }

    /**
     * Creates an instance from a String class name.
     * 
     * @param className
     *            full class name
     * @param classLoader
     *            the class will be loaded with this ClassLoader
     * @return new instance of the class
     * @throws RuntimeException
     *             if class not found or could not be instantiated
     */
    public static Object newInstanceFromName(String className) {
        return newInstanceFromName(className, FactoryHelper.class.getClassLoader());
    }

    /**
     * Creates an instance from a String class name.
     * 
     * @param className
     *            full class name
     * @param classLoader
     *            the class will be loaded with this ClassLoader
     * @return new instance of the class
     * @throws RuntimeException
     *             if class not found or could not be instantiated
     */
    public static Object newInstanceFromName(String className, ClassLoader classLoader) {
        try {
            Class<?> clazz = Class.forName(className, true, classLoader);
            return clazz.newInstance();
        } catch (Exception e) {
            String m = "Couldn't create instance from name " + className + " (" + e.getMessage() + ")";
            LOG.error(m, e);
            throw new RuntimeException(m);
        }
    }
}