shadows/framework/src/main/java/org/robolectric/shadows/ShadowContextImpl.java
@Implementation
  @Nullable
  protected Object getSystemService(String name) {
    if (removedSystemServices.contains(name)) {
      return null;
    }
    if (!systemServices.containsKey(name)) {
      return directlyOn(
          realContextImpl,
          ShadowContextImpl.CLASS_NAME,
          "getSystemService",
          ClassParameter.from(String.class, name));
    }
    return systemServices.get(name);
  }
@Implementation
  @Nullable
  protected Object getSystemService(String name) {
    if (removedSystemServices.contains(name)) {
      return null;
    }
    if (!systemServices.containsKey(name)) {
      return directlyOn(
          realContextImpl,
          ShadowContextImpl.CLASS_NAME,
          "getSystemService",
          ClassParameter.from(String.class, name));
    }
    return systemServices.get(name);
  }
Returns the handle to a system-level service by name. If the service is not available in
Roboletric, or it is set to unavailable in {@link ShadowServiceManager#setServiceAvailability},
{@code null} will be returned.