code: public static Method getMethod(Class clazz, String methodName, Class<?>... parameterTypes) {
          if (clazz == null) {
              return null;
          }
          try {
              return clazz.getDeclaredMethod(methodName, parameterTypes);
          } catch (SecurityException e) {
              e.printStackTrace();
          } catch (NoSuchMethodException e) {
              e.printStackTrace();
          }
          return null;
      }
docs: 获取指定方法
  <p>Function: getMethod</p>
  <p>Description: </p>
  
  @param clazz
  @param methodName
  @param parameterTypes
  @return
  @author acexy@thankjava.com
  @date 2014-12-18 上午9:55:54
  @version 1.0