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/** * Copyright (c) 2005-2010 springside.org.cn * * Licensed under the Apache License, Version 2.0 (the "License"); * * $Id: ReflectionUtils.java 1211 2010-09-10 16:20:45Z calvinxiu $ */ package com.zfsoft.util.reflect; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.ParameterizedType; import java.lang.reflect.Type; import java.util.ArrayList; import java.util.Collection; import java.util.LinkedList; import java.util.List; import org.apache.commons.beanutils.PropertyUtils; import org.apache.commons.lang.StringUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.util.Assert; /** * ??. * * ?????,?Class, ????, ?Util. * * @author calvin */ public class ReflectionUtils { protected static Log logger = LogFactory.getLog(ReflectionUtils.class); /** * Getter. */ public static Object invokeGetterMethod(Object obj, String propertyName) { String getterMethodName = "get" + StringUtils.capitalize(propertyName); return invokeMethod(obj, getterMethodName, new Class[] {}, new Object[] {}); } /** * Setter.valueClass?Setter. */ public static void invokeSetterMethod(Object obj, String propertyName, Object value) { invokeSetterMethod(obj, propertyName, value, null); } /** * Setter. * * @param propertyType Setter,valueClass. */ public static void invokeSetterMethod(Object obj, String propertyName, Object value, Class<?> propertyType) { Class<?> type = propertyType != null ? propertyType : value.getClass(); String setterMethodName = "set" + StringUtils.capitalize(propertyName); invokeMethod(obj, setterMethodName, new Class[] { type }, new Object[] { value }); } /** * ?, private/protected, ??getter. */ public static Object getFieldValue(final Object obj, final String fieldName) { Field field = getAccessibleField(obj, fieldName); if (field == null) { throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]"); } Object result = null; try { result = field.get(obj); } catch (IllegalAccessException e) { logger.error(e); } return result; } /** * , private/protected, ??setter. */ public static void setFieldValue(final Object obj, final String fieldName, final Object value) { Field field = getAccessibleField(obj, fieldName); if (field == null) { throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]"); } try { field.set(obj, value); } catch (IllegalAccessException e) { logger.error(e); } } /** * ?, ?DeclaredField, ?. * * ?Object?, null. */ public static Field getAccessibleField(final Object obj, final String fieldName) { Assert.notNull(obj, "object?"); Assert.hasText(fieldName, "fieldName"); for (Class<?> superClass = obj.getClass(); superClass != Object.class; superClass = superClass .getSuperclass()) { try { Field field = superClass.getDeclaredField(fieldName); field.setAccessible(true); return field; } catch (NoSuchFieldException e) {//NOSONAR // Field??,? } } return null; } /** * , private/protected. * . */ public static Object invokeMethod(final Object obj, final String methodName, final Class<?>[] parameterTypes, final Object[] args) { Method method = getAccessibleMethod(obj, methodName, parameterTypes); if (method == null) { throw new IllegalArgumentException( "Could not find method [" + methodName + "] on target [" + obj + "]"); } try { return method.invoke(obj, args); } catch (Exception e) { throw convertReflectionExceptionToUnchecked(e); } } /** * ?, ?DeclaredMethod,?. * ?Object?, null. * * ?. ?Method,?Method.invoke(Object obj, Object... args) */ public static Method getAccessibleMethod(final Object obj, final String methodName, final Class<?>... parameterTypes) { Assert.notNull(obj, "object?"); for (Class<?> superClass = obj.getClass(); superClass != Object.class; superClass = superClass .getSuperclass()) { try { Method method = superClass.getDeclaredMethod(methodName, parameterTypes); method.setAccessible(true); return method; } catch (NoSuchMethodException e) {//NOSONAR // 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 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 */ @SuppressWarnings("unchecked") 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]; } /** * ??checked exception?unchecked exception. */ public static RuntimeException convertReflectionExceptionToUnchecked(Exception e) { if (e instanceof IllegalAccessException || e instanceof IllegalArgumentException || e instanceof NoSuchMethodException) { return new IllegalArgumentException("Reflection Exception.", e); } else if (e instanceof InvocationTargetException) { return new RuntimeException("Reflection Exception.", ((InvocationTargetException) e).getTargetException()); } else if (e instanceof RuntimeException) { return (RuntimeException) e; } return new RuntimeException("Unexpected Checked Exception.", e); } /** * ????(getter), ??List. * * @param collection ???. * @param propertyName ??????. */ @SuppressWarnings("unchecked") public static List fetchElementPropertyToList(final Collection collection, final String propertyName) { List list = new ArrayList(); try { for (Object obj : collection) { list.add(PropertyUtils.getProperty(obj, propertyName)); } } catch (Exception e) { throw ReflectionUtils.convertReflectionExceptionToUnchecked(e); } return list; } /** * ????(getter), ??. * * @param collection ???. * @param propertyName ??????. * @param separator . */ @SuppressWarnings("unchecked") public static String fetchElementPropertyToString(final Collection collection, final String propertyName, final String separator) { List list = fetchElementPropertyToList(collection, propertyName); return StringUtils.join(list, separator); } /** * Field * @param clazz Class * @return */ public static List<Field> getAllDeclaredField(Class clazz) { List<Field> list = new LinkedList<Field>(); for (Class<?> superClass = clazz; superClass != Object.class; superClass = superClass.getSuperclass()) { Field[] declaredFields = superClass.getDeclaredFields(); for (Field f : declaredFields) list.add(f); } return list; } /** * clazz??? * @param clazz Class * @param targetInterface ?? * @return */ public static boolean isInterface(Class clazz, Class targetInterface) { Class[] face = clazz.getInterfaces(); for (int i = 0, j = face.length; i < j; i++) { if (face[i].getName().equals(targetInterface.getName())) { return true; } else { Class[] face1 = face[i].getInterfaces(); for (int x = 0; x < face1.length; x++) { if (face1[x].getName().equals(targetInterface.getName())) { return true; } else if (isInterface(face1[x], targetInterface)) { return true; } } } } if (null != clazz.getSuperclass()) { return isInterface(clazz.getSuperclass(), targetInterface); } return false; } /** * clazz?, * @param clazz Class * @return */ // public static List<String> getAllCollectionNames(Class clazz) { // List<String> list = new ArrayList<String>(); // // map,class, // Map<Class, Object> tempMap = new HashMap<Class, Object>(); // tempMap.put(clazz, null); // // List<Field> allDeclaredField = ReflectionUtils.getAllDeclaredField(clazz); // for (Field f : allDeclaredField) { // Class typeClass = f.getType(); // // IHibernateEntity? // if (ReflectionUtils.isInterface(typeClass, IHibernateEntity.class)) { // if (!tempMap.containsKey(typeClass)) { // // // list.addAll(getAllCollectionNames(typeClass)); // tempMap.put(typeClass, null); // } // } // if (ReflectionUtils.isInterface(typeClass, Collection.class)) { // list.add(f.getName()); // } // } // return list; // } }