1# ServiceAbility Lifecycle 2 3 4You can override lifecycle callbacks (described in the table below) for ServiceAbility based on service requirements. 5 6 7 **Table 1** ServiceAbility lifecycle callbacks 8 9| API| Description| 10| -------- | -------- | 11| onStart(): void | Called to initialize a ServiceAbility when the ServiceAbility is being created. This callback is invoked only once in the entire lifecycle of a ServiceAbility.| 12| onCommand(want: Want, startId: number): void | Called every time a ServiceAbility is started on the client. You can collect calling statistics and perform initialization operations in this callback.| 13| onConnect(want: Want): rpc.RemoteObject | Called when the ServiceAbility is connected.| 14| onDisconnect(want: Want): void | Called when the connection to the ServiceAbility is disconnected.| 15| onStop(): void | Called when the ServiceAbility is being destroyed. You should override this callback for your ServiceAbility to clear its resources, such as threads and registered listeners.| 16