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/*
 * Copyright 2019 the original author or authors.
 *
 * Licensed under the Apache, 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.gnu.org/licenses/lgpl-3.0.html
 *
 * 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 net.sf.json.util;

import net.sf.json.JSONObject;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

/**
 * Base class for creating Bean instances.

 * 
 * DEFAULT - calls Class.newInstance().
 * 
 *
 * @author Andres Almiray 
 */
public abstract class NewBeanInstanceStrategy {
    /**
     * Calls Class.newInstance()
     */
    public static final NewBeanInstanceStrategy DEFAULT = new DefaultNewBeanInstanceStrategy();

    /**
     * Creates a new instance.
     *
     * @param target the source class
     * @param source additional properties that may be needed to create the
     *               instance
     */
    public abstract Object newInstance(Class target, JSONObject source)
            throws InstantiationException, IllegalAccessException, SecurityException,
            NoSuchMethodException, InvocationTargetException;

    private static final class DefaultNewBeanInstanceStrategy extends NewBeanInstanceStrategy {
        private static final Object[] EMPTY_ARGS = new Object[0];
        private static final Class[] EMPTY_PARAM_TYPES = new Class[0];

        @Override
        public Object newInstance(Class target, JSONObject source) throws InstantiationException,
                IllegalAccessException, SecurityException, NoSuchMethodException,
                InvocationTargetException {
            if (target != null) {
                Constructor c = target.getDeclaredConstructor(EMPTY_PARAM_TYPES);
                c.setAccessible(true);
                try {
                    return c.newInstance(EMPTY_ARGS);
                } catch (InstantiationException e) {
                    // getCause() was added on jdk 1.4
                    String cause = "";
                    try {
                        cause = e.getCause() != null ? "\n" + e.getCause().getMessage() : "";
                    } catch (Throwable t) { /* ignore */ }
                    throw new InstantiationException(
                            "Instantiation of \"" + target + "\" failed. " +
                                    "It's probably because class is an interface, " +
                                    "abstract class, array class, primitive type or void." +
                                    cause);
                }
            }
            return null;
        }
    }
}