public String getDimensionKey() {
        if (dimensionKey == null) {
            dimensionKey = getAppName() + ":" + getService();
        }
        return dimensionKey;
    }
Gets dimension key.

@return the dimension key
fault/fault-tolerance/src/main/java/com/alipay/sofa/rpc/client/aft/InvocationStatDimension.java