1 <html> 2 <body> 3 4 The android.os.health package contains a set of classes to provide data 5 to track the system resources of applications. 6 <p> 7 Applications running in the background are responsible for a significant amount 8 of battery usage on a typical android device. There are several things that 9 applications can do in order to reduce their impact. For example, by using 10 {@link android.app.job.JobScheduler JobScheduler}, an application does not need 11 to independently monitor whether the network is available, whether the device is 12 plugged in, etc. In addition to being simpler to use, the application's 13 services are only started when the required conditions have been met. But even 14 when using the appropriate helper APIs, applications still can reduce their 15 footprint. This package provides more insight into what is going on behind the 16 scenes when an application is running. 17 <p> 18 Application data is tracked by which user id (uid) is using particular 19 resources. A snapshot of an application's measurements can be taken with the 20 {@link android.os.health.SystemHealthManager#takeMyUidSnapshot() SystemHealth.takeMyUidSnapshot()} 21 method. The {@link android.os.health.HealthStats} object returned contains the 22 statistics. 23 <p> 24 <b>HealthStats</b><br> 25 In order to be returned efficiently, the {@link android.os.health.HealthStats} 26 class uses a set of int keys to identify the data returned. The 27 {@link android.os.health.UidHealthStats}, {@link android.os.health.PidHealthStats}, 28 {@link android.os.health.PackageHealthStats} , {@link android.os.health.ProcessHealthStats}, 29 and {@link android.os.health.ServiceHealthStats} classes provide those constants. 30 Each {@link android.os.health.HealthStats} object will be associated with 31 exactly one of those classes. The object returned from 32 {@link android.os.health.SystemHealthManager#takeMyUidSnapshot() SystemHealth.takeMyUidSnapshot()} 33 will be using the {@link android.os.health.UidHealthStats} keys, as it contains all 34 of the data available for that uid. 35 36 37 </body> 38 </html> 39 40
