Java Class New Instance newInstance(Class type)

Description

Creates new instance from the given type.

License

Open Source License

Parameter

Parameter	Description
type	class to reflectively instantiate
T	type of the class

Return

new instance

Declaration

public static <T> T newInstance(Class<T> type) 

Method Source Code

//package com.java2s;
/*/*from  w  w  w.  j  av a  2  s.  c o m*/
 * Copyright (c) 2012 Brown Bag Consulting.
 * This file is part of the ExpressUI project.
 * Author: Juan Osuna
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License Version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * Brown Bag Consulting, Brown Bag Consulting DISCLAIMS THE WARRANTY OF
 * NON INFRINGEMENT OF THIRD PARTY RIGHTS.
 *
 * This program 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the ExpressUI software without
 * disclosing the source code of your own applications. These activities
 * include: offering paid services to customers as an ASP, providing
 * services from a web application, shipping ExpressUI with a closed
 * source product.
 *
 * For more information, please contact Brown Bag Consulting at this
 * address: juan@brownbagconsulting.com.
 */

import java.lang.reflect.*;

public class Main {
    /**
     * Creates new instance from the given type.
     *
     * @param type class to reflectively instantiate
     * @param <T>  type of the class
     * @return new instance
     */
    public static <T> T newInstance(Class<T> type) {
        try {
            return type.newInstance();
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Creates new instance from the given type, based on given parameter types and args.
     *
     * @param type           class to reflectively instantiate
     * @param <T>            type of the class
     * @param parameterTypes used to find the right constructor
     * @param args           passed to constructor
     * @return new instance
     */
    public static <T> T newInstance(Class<T> type, Class[] parameterTypes, Object[] args) {
        try {
            Constructor constructor = type.getDeclaredConstructor(parameterTypes);
            constructor.setAccessible(true);
            return (T) constructor.newInstance(args);
        } catch (NoSuchMethodException e) {
            throw new RuntimeException(e);
        } catch (InvocationTargetException e) {
            throw new RuntimeException(e);
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}

Related

1. newInstance(Class theClass, Class[] parameterTypes, Object[] initargs)
2. newInstance(Class theClass, Object... initArgs)
3. newInstance(Class theClass, String className)
4. newInstance(Class theCls)
5. newInstance(Class type)
6. newInstance(Class type)
7. newInstance(Class type)
8. newInstance(Class type)
9. newInstance(Class type)