package Ġuk . n hs . n hs x . covid 1 9 . android . app . ex posure . en counter . calculation Ċ Ċ import Ġcom . google . android . gms . near by . ex posure notification . Exposure Window Ċ import Ġcom . google . android . gms . near by . ex posure notification . Scan Instance Ċ import Ġuk . n hs . n hs x . covid 1 9 . android . app . remote . data . V 2 Risk Calculation Ċ import Ġuk . n hs . risk score . Risk Score Calculator Configuration Ċ import Ġjavax . inject . Inject Ċ Ċ class ĠCalculate Exposure Risk Ġ@ Inject Ġconstructor ( ĊĠĠĠ Ġprivate Ġval Ġrisk Score Calculator Provider : ĠR isk Score Calculator Provider Ċ ) Ġ{ ĊĊĠĠĠ Ġoperator Ġfun Ġinvoke ( ĊĠĠĠĠĠĠĠ Ġexposure Window : ĠEx posure Window , ĊĠĠĠĠĠĠĠ Ġconfig : ĠR isk Score Calculator Configuration , ĊĠĠĠĠĠĠĠ Ġrisk Calculation : ĠV 2 Risk Calculation ĊĠĠĠ Ġ): ĠDouble Ġ{ ĊĠĠĠĠĠĠĠ Ġval Ġscan Instances Ġ= Ġexposure Window . scan Instances ĊĠĠĠĠĠĠĠĠĠĠĠ Ġ. filter Ġ{ Ġit . seconds Since Last Scan Ġ> Ġ 0 Ġ} ĊĠĠĠĠĠĠĠĠĠĠĠ Ġ. map Ġ{ Ġit . to NH SS can Instance () Ġ} ĊĠĠĠĠĠĠĠ Ġval Ġrisk Score Calculator Ġ= Ġrisk Score Calculator Provider . risk Score Calculator ( config ) ĊĠĠĠĠĠĠĠ Ġreturn Ġ 6 0 Ġ* Ġrisk Score Calculator . calculate ( scan Instances ) Ġ* Ġexposure Window . inf ect ious ness Factor ( risk Calculation ) ĊĠĠĠ Ġ} ĊĊĠĠĠ Ġprivate Ġfun ĠScan Instance . to NH SS can Instance () Ġ= ĊĠĠĠĠĠĠĠ Ġuk . n hs . risk score . Scan Instance ( att enuation Value Ġ= Ġmin Att enuation Db , Ġseconds Since Last Scan Ġ= Ġseconds Since Last Scan ) ĊĊĠĠĠ Ġprivate Ġfun ĠEx posure Window . inf ect ious ness Factor ( risk Calculation : ĠV 2 Risk Calculation ) Ġ= ĊĠĠĠĠĠĠĠ Ġrisk Calculation . inf ect ious ness Weights . get OrNull ( inf ect ious ness ) ĊĠĠĠĠĠĠĠĠĠĠĠ Ġ?: Ġrisk Calculation . inf ect ious ness Weights [ 0 ] Ċ } Ċ