question: @ RpcMethod public void copyImage ( String imageId , String source , String destination , AsyncMethodCallback < Host . AsyncClient . copy_image_call > handler ) throws RpcException { ensureClient ( ) ; CopyImageRequest copyImageRequest = new CopyImageRequest ( ) ; copyImageRequest . setSource ( Util . constructImage ( source , imageId ) ) ; copyImageRequest . setDestination ( Util . constructImage ( destination , imageId ) ) ; logger . info ( "copy_image target {}, request {}" , getHostIp ( ) , copyImageRequest ) ; try { clientProxy . copy_image ( copyImageRequest , handler ) ; } catch ( TException e ) { throw new RpcException ( e . getMessage ( ) ) ; } }
target:  This method performs an asynchronous Thrift call to copy an image from one data store to another. On completion, the specified handler is invoked.