Java Class New Instance newInstance(String type, Class cast)

Description

new Instance

License

Open Source License

Declaration

public static <T> T newInstance(String type, Class<T> cast)
            throws ClassNotFoundException, InstantiationException, IllegalAccessException 

Method Source Code

//package com.java2s;
/*/*from   www . ja v  a2 s  .  c  o m*/
  GRANITE DATA SERVICES
  Copyright (C) 2007 ADEQUATE SYSTEMS SARL
    
  This file is part of Granite Data Services.
    
  Granite Data Services is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 3 of the License, or (at your
  option) any later version.
     
  Granite Data Services 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 Lesser General Public License
  for more details.
     
  You should have received a copy of the GNU Lesser General Public License
  along with this library; if not, see <http://www.gnu.org/licenses/>.
*/

import java.lang.reflect.Constructor;

import java.lang.reflect.InvocationTargetException;

public class Main {
    public static Object newInstance(String type)
            throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        return forName(type).newInstance();
    }

    public static <T> T newInstance(String type, Class<T> cast)
            throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        return forName(type, cast).newInstance();
    }

    public static Object newInstance(String type, Class<?>[] argsClass, Object[] argsValues)
            throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        return newInstance(forName(type), argsClass, argsValues);
    }

    public static <T> T newInstance(Class<T> type, Class<?>[] argsClass, Object[] argsValues)
            throws InstantiationException, IllegalAccessException {
        T instance = null;
        try {
            Constructor<T> constructorDef = type.getConstructor(argsClass);
            instance = constructorDef.newInstance(argsValues);
        } catch (SecurityException e) {
            throw new InstantiationException(e.getMessage());
        } catch (NoSuchMethodException e) {
            throw new InstantiationException(e.getMessage());
        } catch (IllegalArgumentException e) {
            throw new InstantiationException(e.getMessage());
        } catch (InvocationTargetException e) {
            throw new InstantiationException(e.getMessage());
        }
        return instance;
    }

    public static Class<?> forName(String type) throws ClassNotFoundException {
        return Thread.currentThread().getContextClassLoader().loadClass(type);
    }

    @SuppressWarnings("unchecked")
    public static <T> Class<T> forName(String type, Class<T> cast) throws ClassNotFoundException {
        return (Class<T>) Thread.currentThread().getContextClassLoader().loadClass(type);
    }

    public static Constructor<?> getConstructor(String type, Class<?>[] paramTypes)
            throws ClassNotFoundException, NoSuchMethodException {
        return getConstructor(forName(type), paramTypes);
    }

    public static <T> Constructor<T> getConstructor(Class<T> type, Class<?>[] paramTypes)
            throws NoSuchMethodException {
        return type.getConstructor(paramTypes);
    }
}

Related

1. newInstance(String klass)
2. newInstance(String name)
3. newInstance(String name, ClassLoader loader)
4. newInstance(String s)
5. newInstance(String type)
6. newInstance(T obj)
7. newInstance(T obj, Class argType, Object arg)
8. newInstance(Type type)
9. newInstance(Type type)