/** * 初始化 * @param parameter 参数 * @return 实例化的对象 */ protected H init(String parameter){ Type superClass = getClass().getGenericSuperclass();
//获取第二个枚举对象 Type type = ((ParameterizedType) superClass).getActualTypeArguments()[1]; Class<?> clazz = getRawType(type); try {
//获取构造函数列表 final Constructor<?>[] declaredConstructors = clazz.getDeclaredConstructors();
//获取构造函数参数,定义实例化对象的参数类型 final Constructor<?> declaredConstructor = clazz.getDeclaredConstructor(declaredConstructors[0].getParameterTypes()); declaredConstructor.setAccessible(true); return (H) declaredConstructor.newInstance(parameter, "qeqweqwew"); } catch (InstantiationException | IllegalAccessException | NoSuchMethodException | InvocationTargetException e) { throw new ServiceException(e.getMessage(),e.getCause()); } }
/** * type不能直接实例化对象,通过type获取class的类型,然后实例化对象 * @param type 类型 * @return 对象 */ public static Class<?> getRawType(Type type) { if (type instanceof Class) { return (Class<?>) type; } else if (type instanceof ParameterizedType) { ParameterizedType parameterizedType = (ParameterizedType) type; Type rawType = parameterizedType.getRawType(); return (Class<?>) rawType; } else if (type instanceof GenericArrayType) { Type componentType = ((GenericArrayType) type).getGenericComponentType(); return Array.newInstance(getRawType(componentType), 0).getClass(); } else if (type instanceof TypeVariable) { return Object.class; } else if (type instanceof WildcardType) { return getRawType(((WildcardType) type).getUpperBounds()[0]); } else { String className = type == null ? "null" : type.getClass().getName(); throw new IllegalArgumentException("Expected a Class, ParameterizedType, or GenericArrayType, but <" + type + "> is of type " + className); } }
https://www.cnblogs.com/tiancai/p/9603050.html
https://www.cnblogs.com/duanweishi/p/4480163.html