Weak hands cannot be planted, meager skills have no foundation. Shallow wisdom is futile, how can one hope for a good name?扰扰从役倦，屑屑身事微。少壮轻年月，迟暮惜光辉。
cacheGroup, $expire);
}
/**
* Gets a value from the cache.
*
* @param string $key Cache key.
* @param mixed $default Default value if not found.
*
* @return mixed
*/
public function getCache($key, $default = null)
{
$value = wp_cache_get($key, $this->cacheGroup);
return ($value === false) ? $default : $value;
}
/**
* Checks if a cache key is set.
*
* @param string $key Cache key.
*
* @return bool
*/
public function isCacheSet($key)
{
return wp_cache_get($key, $this->cacheGroup) !== false;
}
/**
* Deletes a value from the cache.
*
* @param string $key Cache key.
*
* @return bool True on success, false on failure.
*/
public function deleteCache($key)
{
return wp_cache_