Binary Sensor

The BinarySensor interface represents binary_sensor entities in Home Assistant. When you define a field of type BinarySensor in your SmartBean class and annotate it with @Entity, the framework automatically injects an object that lets you control the corresponding entity in Home Assistant.

@Entity("binary_sensor.motion_kitchen")
private BinarySensor motion;

State

The sensor's state is represented by the BinarySensor.State enum, which mirrors the possible states in Home Assistant: ON, OFF, UNKNOWN and UNAVAILABLE. You can query the sensor's current state using these methods:

Method	Description
getState()	Get the current state of the sensor.
isOn()	Shortcut to check if the sensor is currently on.
getStateAsString()	Returns the original state from the Home Assistant entity.

Attributes

The following attributes of a binary sensor entity can be accessed through simple getter methods:

HA attribute	Method	Description
friendly_name	getFriendlyName()	Friendly name of the entity.
icon	getIcon()	Icon of the entity.
device_class	getDeviceClass()	Device class of the sensor.

You can access any additional attributes that are not directly supported through the getAttributes() method.

Example

public class ASampleBean implements SmartBean {
  
  private SmartBeans sb;

  @Entity("binary_sensor.occupancy_kitchen")
  private BinarySensor occupancy;

  public void someBeanMethod() {
    if(occupancy.isOn()) {
      sb.log("kitchen is occupied");
    }
    else {
      sb.log("kitchen is free");
    }
  }
}

Access Entities Programmatically

In addition to the annotation-based approach, you can programmatically access binary sensors using the getBinarySensor() method of the SmartBeans API. You might prefer this programmatic approach over annotations for example when the entity ID is dynamically generated through business logic and cannot be determined at compile time.

public class ASampleBean implements SmartBean {

  private SmartBeans sb;

  public void someBeanMethod() {
    BinarySensor binarySensor = sb.getBinarySensor("binary_sensor.movement_kitchen");
    if(binarySensor.isOn()) {
      sb.log("There is movement in the kitchen.");
    }
  }
}

note

For improved efficiency, it is recommended to cache entity objects as member variables rather than retrieving them repeatedly. Since the state and attributes of entity objects are cached internally, no additional backend communication is required for multiple state retrievals. Note that initial entity object creation always requires at least one request to the Home Assistant backend.