* @author ls
* @date 2016-11-01
*/ public abstract class ReflectUtil { /** * 获取常量值 * @param clazz 常量类 * @param constName 常量名称 * @return 常量对应的值 */ @SuppressWarnings("unchecked") public static <T> T getConstValue(Class<?> clazz,String constName){ Field field = ReflectUtil.getField(clazz, constName); if(field!=null){ field.setAccessible(true); try { Object object = field.get(null); if(object != null){ return (T) object; } return null; } catch (Exception e) { throw new RuntimeException(e); } } return null; } /** * 为String类型的属性做trim * @param model 去除空格的模型(实体类) * @param propNames 去除属性的名称,只有String类型生效 */ public static void trimFields(Object model, String... propNames){ Assert.notEmpty(propNames, "请指定要去前后空格的属性名"); for(String propName : propNames){ Object val = ReflectUtil.getProperty(model, propName); if(val instanceof String){ String valStr = (String)val; valStr = valStr.trim(); ReflectUtil.setProperty(model, propName, valStr); } } } /** * 获取指定类的所有字段,排除static,final字段 * @param clazz 类型 * @return List<字段> */ public static List<Field> getFields(Class<?> clazz){ List<Field> fieldResult = new ArrayList<Field>(); while(clazz!=Object.class){ try { Field[] fields = clazz.getDeclaredFields(); for (Field field:fields) { int modifiers = field.getModifiers(); //过滤static或final字段 if(Modifier.isStatic(modifiers)||Modifier.isFinal(modifiers)){ continue; } fieldResult.add(field); } } catch (Exception ignore) {} clazz = clazz.getSuperclass(); } return fieldResult; } /** * 获取指定类的所有字段名称,排除static,final字段 * @param clazz 类型 * @return List<字段名称> */ public static List<String> getFieldNames(Class<?> clazz){ List<Field> fields = getFields(clazz); List<String> fieldNames = new ArrayList<String>(fields.size()); for(Field field:fields){ fieldNames.add(field.getName()); } return fieldNames; } /** * 通过反射, 获得定义 Class 时声明的父类的泛型参数的类型 * 如: public EmployeeDao extends BaseDao<Employee, String> * @param clazz * @param index * @return */ public static Class<?> getSuperClassGenricType(Class<?> clazz, int index){ Type genType = clazz.getGenericSuperclass(); if(!(genType instanceof ParameterizedType)){ return Object.class; } Type [] params = ((ParameterizedType)genType).getActualTypeArguments(); if(index >= params.length || index < 0){ return Object.class; } if(!(params[index] instanceof Class)){ return Object.class; } return (Class<?>) params[index]; } /** * 通过反射, 获得 Class 定义中声明的父类的泛型参数类型 * 如: public EmployeeDao extends BaseDao<Employee, String> * @param <T> * @param clazz * @return */ @SuppressWarnings("unchecked") public static<T> Class<T> getSuperGenericType(Class<?> clazz){ return (Class<T>) getSuperClassGenricType(clazz, 0); } /** * 拷贝属性 * @param source * @param target * @param ignorProps 忽略的属性 */ @SuppressWarnings({ "rawtypes", "unchecked" }) public static void copyProps(Object source, Object target, String...ignoreProps) { if(source instanceof Map){ Map sourceMap = (Map)source; Set<String> ignorPropsSet = new HashSet<String>(); if(ArrayUtils.isNotEmpty(ignoreProps)){ for(String prop : ignoreProps){ ignorPropsSet.add(prop); } } Set<Map.Entry<Object, Object>> entrySet = sourceMap.entrySet(); for(Map.Entry<Object, Object> e:entrySet){ if(ignorPropsSet.isEmpty()){ setProperty(target, e.getKey().toString(), e.getValue()); }else if(!ignorPropsSet.contains(e.getKey())){ setProperty(target, e.getKey().toString(), e.getValue()); } } }else if(source instanceof List){ List sourceList = (List)source; if(target instanceof List){ List targetList = (List)target; for(Object obj:sourceList){ targetList.add(obj); } } }else{ BeanUtils.copyProperties(source, target, ignoreProps); } } /** * 拷贝非空属性,指定copy的属性 * @param source 资源 * @param target 目标 * @param incProps 包含的属性 */ public static void copyPropsInc(Object source, Object target, String...incProps) { if(ArrayUtils.isNotEmpty(incProps)){ Set<String> incPropsSet = new HashSet<String>(incProps.length); for(String prop : incProps){ incPropsSet.add(prop); } List<String> fieldNames = getFieldNames(source.getClass()); for(String fieldName : fieldNames){ if(!incPropsSet.contains(fieldName)){ continue; } Object value = getProperty(source, fieldName); setProperty(target, fieldName, value); } } } /** * java bean转Map * @param bean * @param propNames 需要放到map中的属性名称 * @return */ public static Map<String,Object> beanToMap(Object bean, String...propNames) { Map<String,Object> rtn = new HashMap<String,Object>(); if(ArrayUtils.isEmpty(propNames)){ List<String> fieldNames = getFieldNames(bean.getClass()); for (String fieldName: fieldNames) { Object value = getProperty(bean, fieldName); rtn.put(fieldName, value); } }else{ for(String propName: propNames){ Object value = getProperty(bean, propName); rtn.put(propName, value); } } return rtn; } /** * Map 转 JavaBean * @param map * @param clazz * @return */ public static <T> T mapToBean(Map<String,?> map,Class<T> clazz){ T bean = newInstance(clazz); for(Entry<String, ?> me:map.entrySet()){ setProperty(bean, me.getKey(), me.getValue(), true); } return bean; } /** * 反射无参创建对象 * @param clazz * @return */ public static <T> T newInstance(Class<T> clazz){ return BeanUtils.instantiate(clazz); } /** * 获取私有属性Value * @param bean * @param name * @return */ public static Object getPrivateProperty(Object bean, String name){ try { Field field = getField(bean.getClass(), name); if(field!=null){ field.setAccessible(true); return field.get(bean); }else{ throw new RuntimeException("The field [ "+field+"] in ["+bean.getClass().getName()+"] not exists"); } } catch (Exception e) { throw new RuntimeException(e); } } /** * 设置私有属性Value * @param bean * @param name * @param value */ public static void setPrivateProperty(Object bean, String name, Object value){ try { Field field = getField(bean.getClass(), name); if(field!=null){ field.setAccessible(true); field.set(bean, value); }else{ throw new RuntimeException("The field [ "+field+"] in ["+bean.getClass().getName()+"] not exists"); } } catch (Exception e) { throw new RuntimeException(e); } } /** * 获取字段 * @param clazz * @param name * @return * @throws Exception */ public static Field getField(Class<?> clazz,String name){ return ReflectionUtils.findField(clazz, name); } /** * 获取字段类型 * @param clazz * @param name * @return * @throws Exception */ public static Class<?> getFieldType(Class<?> clazz,String name) { Field field = getField(clazz, name); if(field!=null){ return field.getType(); }else{ throw new RuntimeException("Cannot locate field " + name + " on " + clazz); } } /** * @see #setProperty(Object, String, Object, boolean) * @param bean * @param name * @param value */ public static void setProperty(Object bean, String name, Object value){ setProperty(bean, name, value, false); } /** * 设置Bean属性,类型自动转换,如果涉及日期转换,只支持long类型或者long值的字符串 * @param bean * @param name * @param value * @param ignoreError 忽略找不到属性错误 * @throws Exception */ public static void setProperty(Object bean, String name, Object value, boolean ignoreError) { if (value != null) { try { Class<?> type = getPropertyType(bean, name); if (type != null) { if (!value.getClass().equals(type)) { if (TypeUtils.isAssignable(Date.class, type) && value instanceof String) { try { value = new Date(Long.parseLong((String) value)); } catch (NumberFormatException ignore) {} } else { //如果把一个字符串转换成数值,去除数值的, if(TypeUtils.isAssignable(Number.class, type)){ value = StringUtils.deleteAny(value.toString(), ","); } value = ConvertUtils.convert(value, type); } } } PropertyUtils.setProperty(bean, name, value); } catch (NestedNullException e) { createNestedBean(bean, name); setProperty(bean, name, value, ignoreError); } catch (NoSuchMethodException e) { if (!ignoreError) throw new RuntimeException(e); }catch(Exception e){ throw new RuntimeException(e); } } } /** * 获取属性,忽略NestedNullException * * @param bean * @param name * @return */ public static Object getProperty(Object bean, String name){ try { return PropertyUtils.getProperty(bean, name); } catch (NestedNullException ignore) { return null; }catch(Exception e){ throw new RuntimeException(e); } } /** * 获取属性类型,忽略NestedNullException * * @param bean * @param name * @return */ public static Class<?> getPropertyType(Object bean, String name) { try { return PropertyUtils.getPropertyType(bean, name); } catch (NestedNullException ignore) { return null; }catch(Exception e){ throw new RuntimeException(e); } } /** * 创建内嵌对象 * * @param bean * @param name */ private static void createNestedBean(Object bean, String name){ String[] names = name.split("[.]"); if (names.length == 1) return; try { StringBuilder nestedName = new StringBuilder(); for (int i = 0; i < names.length - 1; i++) { String n = names[i]; if (i > 0) { nestedName.append("." + n); } else { nestedName.append(n); } Object val = PropertyUtils.getProperty(bean, nestedName.toString()); if (val == null) { PropertyUtils.setProperty(bean, nestedName.toString(), PropertyUtils.getPropertyType(bean, nestedName.toString()).newInstance()); } } } catch (Exception e) { throw new RuntimeException(e); } } /** * 获取n个类,相同的父类类型,如果多个相同的父类,获取最接近的的, * 如果传递的对象包含Object.class 直接返回null * @param clazzs * @return 相同的父类Class */ public static Class<?> getEqSuperClass(Class<?> ...clazzs){ Validate.notEmpty(clazzs); List<List<Class<?>>> container = new ArrayList<List<Class<?>>>(clazzs.length); for(Class<?>clazz :clazzs){ if(clazz==Object.class)return null; List<Class<?>> superClazz = new ArrayList<Class<?>>(5); for(clazz=clazz.getSuperclass();clazz!=Object.class;clazz=clazz.getSuperclass()){ superClazz.add(clazz); } container.add(superClazz); } List<Class<?>> result = new ArrayList<Class<?>>(5); Iterator<List<Class<?>>> it = container.iterator(); int len =0; while(it.hasNext()){ if(len == 0){ result.addAll(it.next()); }else{ result.retainAll(it.next()); if(CollectionUtils.isEmpty(result)){ break; } } len++; } //不管相同父类有几个,返回最接近的 if(CollectionUtils.isNotEmpty(result)){ return result.get(0); } return Object.class; } }