BeanUtils初始化對象

BeanUtils使用instantiateClass初始化對象注意

1.必須保證初始化類必須有public默認無參數構造器，注意初始化內部類時，內部類必須是靜態的，否則報錯！

源碼如下

/**
	 * Instantiate a class using its no-arg constructor.
	 * As this method doesn't try to load classes by name, it should avoid
	 * class-loading issues.
	 * <p>Note that this method tries to set the constructor accessible
	 * if given a non-accessible (that is, non-public) constructor.
	 * @param clazz class to instantiate
	 * @return the new instance
	 * @throws BeanInstantiationException if the bean cannot be instantiated
	 */
	public static <T> T instantiateClass(Class<T> clazz) throws BeanInstantiationException {
		Assert.notNull(clazz, "Class must not be null");
		if (clazz.isInterface()) {
			throw new BeanInstantiationException(clazz, "Specified class is an interface");
		}
		try {
			return instantiateClass(clazz.getDeclaredConstructor());
		}
		catch (NoSuchMethodException ex) {
			throw new BeanInstantiationException(clazz, "No default constructor found", ex);
		}
	}