Java tutorial
/* * Copyright 2008-2009 MOPAS(Ministry of Public Administration and Security). * * 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 egovframework.rte.fdl.string; import java.lang.reflect.Constructor; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * ?? ? ? ? * <p> * <b>NOTE:</b> Class ? ? ? ?. * @author * @since 2009.06.01 * @version 1.0 * @see <pre> * == ?(Modification Information) == * * ? ? * ------- -------- --------------------------- * 2009.06.01 ? * * </pre> */ public class EgovObjectUtil { private static Log log = LogFactory.getLog(EgovObjectUtil.class); private EgovObjectUtil() { } /** * ? ? . * @param className * @return * @throws ClassNotFoundException * @throws Exception */ public static Class<?> loadClass(String className) throws ClassNotFoundException, Exception { Class<?> clazz = null; try { clazz = Thread.currentThread().getContextClassLoader().loadClass(className); } catch (ClassNotFoundException e) { throw new ClassNotFoundException(); } catch (Exception e) { throw new Exception(e); } if (clazz == null) { clazz = Class.forName(className); } return clazz; } /** * ? ? ? . * @param className * @return * @throws ClassNotFoundException * @throws InstantiationException * @throws IllegalAccessException * @throws Exception */ public static Object instantiate(String className) throws ClassNotFoundException, InstantiationException, IllegalAccessException, Exception { Class<?> clazz; try { clazz = loadClass(className); return clazz.newInstance(); } catch (ClassNotFoundException e) { if (log.isErrorEnabled()) log.error(className + " : Class is can not instantialized."); throw new ClassNotFoundException(); } catch (InstantiationException e) { if (log.isErrorEnabled()) log.error(className + " : Class is can not instantialized."); throw new InstantiationException(); } catch (IllegalAccessException e) { if (log.isErrorEnabled()) log.error(className + " : Class is not accessed."); throw new IllegalAccessException(); } catch (Exception e) { if (log.isErrorEnabled()) log.error(className + " : Class is not accessed."); throw new Exception(e); } } /** * ? ? ?? ?? ? . ) Class <?> * clazz = EgovObjectUtil.loadClass(this.mapClass); * Constructor <?> constructor = * clazz.getConstructor(new Class * []{DataSource.class, String.class}); Object [] * params = new Object []{getDataSource(), * getUsersByUsernameQuery()}; * this.usersByUsernameMapping = * (EgovUsersByUsernameMapping) * constructor.newInstance(params); * @param className * @return * @throws ClassNotFoundException * @throws InstantiationException * @throws IllegalAccessException * @throws Exception */ public static Object instantiate(String className, String[] types, Object[] values) throws ClassNotFoundException, InstantiationException, IllegalAccessException, Exception { Class<?> clazz; Class<?>[] classParams = new Class[values.length]; Object[] objectParams = new Object[values.length]; try { clazz = loadClass(className); for (int i = 0; i < values.length; i++) { classParams[i] = loadClass(types[i]); objectParams[i] = values[i]; } Constructor<?> constructor = clazz.getConstructor(classParams); return constructor.newInstance(values); } catch (ClassNotFoundException e) { if (log.isErrorEnabled()) log.error(className + " : Class is can not instantialized."); throw new ClassNotFoundException(); } catch (InstantiationException e) { if (log.isErrorEnabled()) log.error(className + " : Class is can not instantialized."); throw new InstantiationException(); } catch (IllegalAccessException e) { if (log.isErrorEnabled()) log.error(className + " : Class is not accessed."); throw new IllegalAccessException(); } catch (Exception e) { if (log.isErrorEnabled()) log.error(className + " : Class is not accessed."); throw new Exception(e); } } /** * ? Null ? ?. * @param object * @return Null? true / Null? false */ public static boolean isNull(Object object) { return ((object == null) || object.equals(null)); } }