code: public boolean containsValue(String group, String value) {
  		group = StrUtil.nullToEmpty(group).trim();
  		readLock.lock();
  		try {
  			final LinkedHashMap<String, String> valueMap = this.get(group);
  			if (MapUtil.isNotEmpty(valueMap)) {
  				return valueMap.containsValue(value);
  			}
  		} finally {
  			readLock.unlock();
  		}
  		return false;
  	}
docs: 指定分组中是否包含指定值
  
  @param group 分组
  @param value 值
  @return 是否包含值