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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.base.dao.sql; import java.lang.reflect.Array; 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.math.BigDecimal; import java.math.BigInteger; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.Map; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.util.Assert; import com.utils.DateUtils; /** * ??. * * ?????,?Class, ????, ?Util. * * @author calvin */ public class ReflectionUtils { private static Logger logger = LoggerFactory.getLogger(ReflectionUtils.class); private static Map<Class, Object> primitiveDefaults; static { Map<Class, Object> map = new HashMap<Class, Object>(); map.put(Boolean.TYPE, Boolean.FALSE); map.put(Byte.TYPE, Byte.valueOf((byte) 0)); map.put(Short.TYPE, Short.valueOf((short) 0)); map.put(Character.TYPE, new Character((char) 0)); map.put(Integer.TYPE, Integer.valueOf(0)); map.put(Long.TYPE, Long.valueOf(0L)); map.put(Float.TYPE, new Float(0.0f)); map.put(Double.TYPE, new Double(0.0)); map.put(BigInteger.class, new BigInteger("0")); map.put(BigDecimal.class, new BigDecimal(0.0)); primitiveDefaults = Collections.unmodifiableMap(map); } public static Object convertValue(Object value, Class toType) { Object result = null; if (value != null) { if (value.getClass().isArray() && toType.isArray()) { Class componentType = toType.getComponentType(); result = Array.newInstance(componentType, Array.getLength(value)); for (int i = 0, icount = Array.getLength(value); i < icount; i++) { Array.set(result, i, convertValue(Array.get(value, i), componentType)); } } else { if ((toType == Integer.class) || (toType == Integer.TYPE)) result = Integer.valueOf((int) longValue(value)); if ((toType == Double.class) || (toType == Double.TYPE)) result = new Double(doubleValue(value)); if ((toType == Boolean.class) || (toType == Boolean.TYPE)) result = booleanValue(value) ? Boolean.TRUE : Boolean.FALSE; if ((toType == Byte.class) || (toType == Byte.TYPE)) result = Byte.valueOf((byte) longValue(value)); if ((toType == Character.class) || (toType == Character.TYPE)) result = new Character((char) longValue(value)); if ((toType == Short.class) || (toType == Short.TYPE)) result = Short.valueOf((short) longValue(value)); if ((toType == Long.class) || (toType == Long.TYPE)) result = Long.valueOf(longValue(value)); if ((toType == Float.class) || (toType == Float.TYPE)) result = new Float(doubleValue(value)); if (toType == BigInteger.class) result = bigIntValue(value); if (toType == BigDecimal.class) result = bigDecValue(value); if (toType == String.class) result = stringValue(value); if (toType == Date.class) { result = DateUtils.toDate(stringValue(value)); } if (Enum.class.isAssignableFrom(toType)) result = enumValue((Class<Enum>) toType, value); } } else { if (toType.isPrimitive()) { result = primitiveDefaults.get(toType); } } return result; } public static boolean booleanValue(Object value) { if (value == null) return false; Class c = value.getClass(); if (c == Boolean.class) return ((Boolean) value).booleanValue(); if (c == Character.class) return ((Character) value).charValue() != 0; if (value instanceof Number) return ((Number) value).doubleValue() != 0; return true; // non-null } public static Enum<?> enumValue(Class toClass, Object o) { Enum<?> result = null; if (o == null) { result = null; } else if (o instanceof String[]) { result = Enum.valueOf(toClass, ((String[]) o)[0]); } else if (o instanceof String) { result = Enum.valueOf(toClass, (String) o); } return result; } public static long longValue(Object value) throws NumberFormatException { if (value == null) return 0L; Class c = value.getClass(); if (c.getSuperclass() == Number.class) return ((Number) value).longValue(); if (c == Boolean.class) return ((Boolean) value).booleanValue() ? 1 : 0; if (c == Character.class) return ((Character) value).charValue(); return Long.parseLong(stringValue(value, true)); } private static double processDecimal(Object value) { String objs = String.valueOf(value); double dbvalue = Double.valueOf(objs); BigDecimal bg = new BigDecimal(dbvalue); double f1 = bg.setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue(); return f1; } public static double doubleValue(Object value) throws NumberFormatException { if (value == null) return 0.0; Class c = value.getClass(); if (c.getSuperclass() == Number.class) { double f1 = processDecimal(value); return f1; } if (c == Boolean.class) return ((Boolean) value).booleanValue() ? 1 : 0; if (c == Character.class) return ((Character) value).charValue(); String s = stringValue(value, true); return (s.length() == 0) ? 0.0 : Double.parseDouble(s); } public static BigInteger bigIntValue(Object value) throws NumberFormatException { if (value == null) return BigInteger.valueOf(0L); Class c = value.getClass(); if (c == BigInteger.class) return (BigInteger) value; if (c == BigDecimal.class) return ((BigDecimal) value).toBigInteger(); if (c.getSuperclass() == Number.class) return BigInteger.valueOf(((Number) value).longValue()); if (c == Boolean.class) return BigInteger.valueOf(((Boolean) value).booleanValue() ? 1 : 0); if (c == Character.class) return BigInteger.valueOf(((Character) value).charValue()); return new BigInteger(stringValue(value, true)); } public static BigDecimal bigDecValue(Object value) throws NumberFormatException { if (value == null) return BigDecimal.valueOf(0L); Class c = value.getClass(); if (c == BigDecimal.class) return (BigDecimal) value; if (c == BigInteger.class) return new BigDecimal((BigInteger) value); if (c.getSuperclass() == Number.class) return BigDecimal.valueOf(processDecimal(value)); if (c == Boolean.class) return BigDecimal.valueOf(((Boolean) value).booleanValue() ? 1 : 0); if (c == Character.class) return BigDecimal.valueOf(((Character) value).charValue()); return new BigDecimal(stringValue(value, true)); } public static String stringValue(Object value, boolean trim) { String result; if (value == null) { result = null; } else { result = value.toString(); if (trim) { result = result.trim(); } } return result; } public static String stringValue(Object value) { return stringValue(value, false); } /** * 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.getMessage()); } 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.getMessage()); } } /** * ?, ?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); } }