Filamentary Flows and Clump-fed High-mass Star Formation in G22

G22 is a hub-filament system composed of four supercritical filaments. Velocity gradients are detected along three filaments. A total mass infall rate of 440 $M_{\odot }$~Myr${}^{-1}$ would double the hub mass in about six free-fall times. The most massive clump C1 would be in global collapse with an infall velocity of 0.31 km s${}^{-1}$ and a mass infall rate of $7.2\times {10}^{-4}$ $M_{\odot }$ yr${}^{-1}$, which is supported by the prevalent HCO${}^{+}$ (3-2) and ${}^{13}$CO (3-2) blue profiles. A hot molecular core (SMA1) was revealed in C1. At the SMA1 center, there is a massive protostar (MIR1) driving multipolar outflows which are associated with clusters of class I methanol masers. MIR1 may be still growing with an accretion rate of $7\times {10}^{-5}$ $M_{\odot }$ yr${}^{-1}$. Filamentary flows, clump-scale collapse, core-scale accretion coexist in G22, suggesting that high-mass starless cores may not be prerequisite to form high-mass stars. In the high-mass star formation process, the central protostar, the core, and the clump can grow in mass simultaneously.