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/** * @(#)ReflectionUtil.java 2011-9-6 * * Copyright 2000-2011 by ChinanetCenter Corporation. * * All rights reserved. * * This software is the confidential and proprietary information of * ChinanetCenter Corporation ("Confidential Information"). You * shall not disclose such Confidential Information and shall use * it only in accordance with the terms of the license agreement * you entered into with ChinanetCenter. * */ package com.zhuangjy.dao; import org.apache.commons.beanutils.BeanUtils; import org.apache.commons.beanutils.ConvertUtils; import org.apache.commons.beanutils.PropertyUtils; import org.apache.commons.beanutils.converters.DateConverter; import org.apache.commons.lang3.StringUtils; import org.apache.commons.lang3.builder.ToStringBuilder; import org.apache.commons.lang3.builder.ToStringStyle; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.lang.annotation.Annotation; import java.lang.reflect.*; import java.util.ArrayList; import java.util.Collection; import java.util.Date; import java.util.List; /** * ??Util?. * * ?????,?Class,????,?Util. * * @author * @version 1.1 2011-9-2 * @since 1.0 */ public abstract class ReflectionUtil { private static Logger logger = LoggerFactory.getLogger(ReflectionUtil.class); static { DateConverter dc = new DateConverter(null); dc.setUseLocaleFormat(true); dc.setPatterns(new String[] { "yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss" }); ConvertUtils.register(dc, Date.class); } /** * ?, private/protected, ??getter. */ public static Object getFieldValue(final Object object, final String fieldName) { Field field = getDeclaredField(object, fieldName); if (field == null) throw new IllegalArgumentException( "Could not find field [" + fieldName + "] on target [" + object + "]"); makeAccessible(field); Object result = null; try { result = field.get(object); } catch (IllegalAccessException e) { logger.error("??{}", e.getMessage()); } return result; } /** * ?, ?getter. */ public static String getProperty(final Object object, final String propertyName) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException { return BeanUtils.getProperty(object, propertyName); } /** * , private/protected, ??setter. */ public static void setFieldValue(final Object object, final String fieldName, final Object value) { Field field = getDeclaredField(object, fieldName); if (field == null) throw new IllegalArgumentException( "Could not find field [" + fieldName + "] on target [" + object + "]"); makeAccessible(field); try { field.set(object, value); } catch (IllegalAccessException e) { logger.error("??:{}", e.getMessage()); } } /** * , ?setter. */ public static void setProperty(final Object object, final String fieldName, final Object value) throws InvocationTargetException, IllegalAccessException { BeanUtils.setProperty(object, fieldName, value); } /** * , private/protected. */ public static Object invokeMethod(final Object object, final String methodName, final Class<?>[] parameterTypes, final Object[] parameters) throws InvocationTargetException, IllegalAccessException { Method method = getDeclaredMethod(object, methodName, parameterTypes); if (method == null) throw new IllegalArgumentException( "Could not find method [" + methodName + "] on target [" + object + "]"); method.setAccessible(true); return method.invoke(object, parameters); } /** * ?, ?DeclaredField. * * ?Object?, null. */ protected static Field getDeclaredField(final Object object, final String fieldName) { ValidateUtil.notNull(object, "object?"); ValidateUtil.notEmpty(fieldName, "fieldName"); for (Class<?> superClass = object.getClass(); superClass != Object.class; superClass = superClass .getSuperclass()) { try { return superClass.getDeclaredField(fieldName); } catch (NoSuchFieldException e) { // Field??,? } } return null; } /** * ?DeclaredFields. * * @param object * @return */ public static Field[] getDeclaredFields(final Object object) { ValidateUtil.notNull(object, "object?"); return object.getClass().getDeclaredFields(); } /** * Field?. */ protected static void makeAccessible(final Field field) { if (!Modifier.isPublic(field.getModifiers()) || !Modifier.isPublic(field.getDeclaringClass().getModifiers())) { field.setAccessible(true); } } /** * ?,?DeclaredMethod. * * ?Object?, null. */ protected static Method getDeclaredMethod(Object object, String methodName, Class<?>[] parameterTypes) { ValidateUtil.notNull(object, "object?"); for (Class<?> superClass = object.getClass(); superClass != Object.class; superClass = superClass .getSuperclass()) { try { return superClass.getDeclaredMethod(methodName, parameterTypes); } catch (NoSuchMethodException e) { // Method??,? } } return null; } /** * ??,Class?. , Object.class. eg. public UserDao * extends * HibernateDao<User> * * @param clazz * The class to introspect * @return the first generic declaration, or Object.class if cannot be * determined */ @SuppressWarnings("unchecked") public static <T> Class<T> getSuperClassGenricType(final Class<?> clazz) { return (Class<T>) getSuperClassGenricType(clazz, 0); } /** * ??,Class?. , Object.class. * * public UserDao extends HibernateDao<User,Long> * * @param clazz * clazz The class to introspect * @param index * the Index of the generic ddeclaration,start from 0. * @return the index generic declaration, or Object.class if cannot be * determined */ public static Class<?> getSuperClassGenricType(final Class<?> clazz, final int index) { Type genType = clazz.getGenericSuperclass(); if (!(genType instanceof ParameterizedType)) { logger.warn(clazz.getSimpleName() + "'s superclass not ParameterizedType"); return Object.class; } Type[] params = ((ParameterizedType) genType).getActualTypeArguments(); if (index >= params.length || index < 0) { logger.warn("Index: " + index + ", Size of " + clazz.getSimpleName() + "'s Parameterized Type: " + params.length); return Object.class; } if (!(params[index] instanceof Class)) { logger.warn(clazz.getSimpleName() + " not set the actual class on superclass generic parameter"); return Object.class; } return (Class<?>) params[index]; } /** * ????(getter), ??List. * * @param collection * ???. * @param propertyName * ??????. */ public static List<?> convertElementPropertyToList(final Collection<?> collection, final String propertyName) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException { List<Object> list = new ArrayList<Object>(); for (Object obj : collection) { list.add(PropertyUtils.getProperty(obj, propertyName)); } return list; } /** * ????(getter), ??. * * @param collection * ???. * @param propertyName * ??????. * @param separator * . */ public static String convertElementPropertyToString(final Collection<?> collection, final String propertyName, final String separator) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException { List<?> list = convertElementPropertyToList(collection, propertyName); return StringUtils.join(list, separator); } /** * ??toString()????logger debug * * @param obj * ?? * @return toString result * @since 2.0 */ public static String objectToString(Object obj) { return ToStringBuilder.reflectionToString(obj, ToStringStyle.SHORT_PREFIX_STYLE); } /** * @since 2.0.29 */ public static Object getPropertyValue(Object bean, String name) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException { return PropertyUtils.getProperty(bean, name); } public static List<Field> getFieldsByAnnotation(Class<? extends Annotation> annotationType, Class clz) { List<Field> list = new ArrayList<>(); getFieldsByAnnotation(list, annotationType, clz); return list; } private static void getFieldsByAnnotation(List<Field> list, Class<? extends Annotation> annotation, Class clz) { if (clz.equals(Object.class)) { return; } Field[] fields = clz.getDeclaredFields(); if (fields == null || fields.length == 0) { return; } for (Field f : fields) { f.setAccessible(true); if (f.getAnnotation(annotation) != null) { list.add(f); } } } }