dwr+ssh2项目整合.zip

package com.gaojunwei.dao; 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 org.apache.commons.lang.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.util.Assert; /** * 反射工具类. * * 提供访问私有变量,获取泛型类型Class, 提取集合中元素的属性, 转换字符串到对象等Util函数. * * @author calvin */ public class ReflectionUtils { private static Logger logger = LoggerFactory.getLogger(ReflectionUtils.class); /** * 调用Getter方法. */ public static Object invokeGetterMethod(Object obj, String propertyName) { String getterMethodName = "get" + StringUtils.capitalize(propertyName); return invokeMethod(obj, getterMethodName, new Class[] {}, new Object[] {}); } /** * 调用Setter方法.使用value的Class来查找Setter方法. */ public static void invokeSetterMethod(Object obj, String propertyName, Object value) { invokeSetterMethod(obj, propertyName, value, null); } /** * 调用Setter方法. * * @param propertyType 用于查找Setter方法,为空时使用value的Class替代. */ 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 }); } /** * 直接读取对象属性值, 无视private/protected修饰符, 不经过getter函数. */ 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("不可能抛出的异常{}", e.getMessage()); } return result; } /** * 直接设置对象属性值, 无视private/protected修饰符, 不经过setter函数. */ 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("不可能抛出的异常:{}", e.getMessage()); } } /** * 循环向上转型, 获取对象的DeclaredField, 并强制设置为可访问. * * 如向上转型到Object仍无法找到, 返回null. */ public static Field getAccessibleField(final Object obj, final String fieldName) { Assert.notNull(obj, "object不能为空"); 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不在当前类定义,继续向上转型 } } return null; } /** * 直接调用对象方法, 无视private/protected修饰符. * 用于一次性调用的情况. */ 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); } } /** * 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问. * 如向上转型到Object仍无法找到, 返回null. * * 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args) */ public static Method getAccessibleMethod(final Object obj, final String methodName, final Class<?>... parameterTypes) { Assert.notNull(obj, "object不能为空"); 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不在当前类定义,继续向上转型 } } return null; } /** * 通过反射, 获得Class定义中声明的父类的泛型参数的类型. * 如无法找到, 返回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); } /** * 通过反射, 获得Class定义中声明的父类的泛型参数的类型. * 如无法找到, 返回Object.class. * * 如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]; } /** * 将反射时的checked exception转换为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); } }