工具类：判断一个类是否是给定类的子类

public class ClassUtils {/*** Checks if a class is a subclass of a class with the specified name. Used* as an instanceOf without having to load the class, useful when trying to* check for classes that might not be available in the runtime JRE.** @param clazz*            The class to check* @param className*            The class name to look for in the super classes* @return true if the class extends a class by the specified name.*/public static boolean extendsClass(final Class<?> clazz, String className) {Class<?> superClass = clazz.getSuperclass();while (superClass != null) {if (superClass.getName().equals(className)) {return true;}superClass = superClass.getSuperclass();}return false;}}