Document system properties

Author: trask

articles/azure-monitor/app/java-standalone-config.md

@@ -100,6 +100,9 @@ If cloud role name is not set, the Application Insights resource's name will be
 You can also set the cloud role name using the environment variable `APPLICATIONINSIGHTS_ROLE_NAME`
 (which will then take precedence over cloud role name specified in the json configuration).
 
+Or you can set the cloud role name using the Java system property `applicationinsights.role.name`
+(which will also take precedence over cloud role name specified in the json configuration).
+
 If you have multiple applications deployed in the same JVM and want them to send telemetry to different cloud role
 names, see [Cloud role name overrides (preview)](#cloud-role-name-overrides-preview).
 
@@ -121,6 +124,9 @@ If you want to set the cloud role instance to something different rather than th
 You can also set the cloud role instance using the environment variable `APPLICATIONINSIGHTS_ROLE_INSTANCE`
 (which will then take precedence over cloud role instance specified in the json configuration).
 
+Or you can set the cloud role instance using the Java system property `applicationinsights.role.instance`
+(which will also take precedence over cloud role instance specified in the json configuration).
+
 ## Sampling
 
 Sampling is helpful if you need to reduce cost.