This is the description of the Java API bindings for the Ambient Light Bricklet. General information and technical specifications for the Ambient Light Bricklet are summarized in its hardware description.
An installation guide for the Java API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | import com.tinkerforge.BrickletAmbientLight;
import com.tinkerforge.IPConnection;
public class ExampleSimple {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "ABC"; // Change to your UID
// Note: To make the example code cleaner we do not handle exceptions. Exceptions you
// might normally want to catch are described in the documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletAmbientLight al = new BrickletAmbientLight(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Get current illuminance (unit is Lux/10)
int illuminance = al.getIlluminance(); // Can throw com.tinkerforge.TimeoutException
System.out.println("Illuminance: " + illuminance/10.0 + " Lux");
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
|
Download (ExampleCallback.java)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | import com.tinkerforge.BrickletAmbientLight;
import com.tinkerforge.IPConnection;
public class ExampleCallback {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "ABC"; // Change to your UID
// Note: To make the example code cleaner we do not handle exceptions. Exceptions you
// might normally want to catch are described in the documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletAmbientLight al = new BrickletAmbientLight(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Set Period for illuminance callback to 1s (1000ms)
// Note: The illuminance callback is only called every second if the
// illuminance has changed since the last call!
al.setIlluminanceCallbackPeriod(1000);
// Add and implement illuminance listener (called if illuminance changes)
al.addIlluminanceListener(new BrickletAmbientLight.IlluminanceListener() {
public void illuminance(int illuminance) {
System.out.println("Illuminance: " + illuminance/10.0 + " Lux");
}
});
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
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Download (ExampleThreshold.java)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | import com.tinkerforge.BrickletAmbientLight;
import com.tinkerforge.IPConnection;
public class ExampleThreshold {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "ABC"; // Change to your UID
// Note: To make the example code cleaner we do not handle exceptions. Exceptions you
// might normally want to catch are described in the documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletAmbientLight al = new BrickletAmbientLight(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Get threshold callbacks with a debounce time of 10 seconds (10000ms)
al.setDebouncePeriod(10000);
// Configure threshold for "greater than 200 Lux" (unit is Lux/10)
al.setIlluminanceCallbackThreshold('>', (short)(200*10), (short)0);
// Add and implement illuminance reached listener
// (called if illuminance is greater than 200 lux)
al.addIlluminanceReachedListener(new BrickletAmbientLight.IlluminanceReachedListener() {
public void illuminanceReached(int illuminance) {
System.out.println("We have: " + illuminance/10.0 + " Lux.");
System.out.println("Too bright, close the curtains!");
}
});
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
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Generally, every method of the Java bindings that returns a value can throw a TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody unplugs the device). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.
Beside the TimeoutException there is also a NotConnectedException that is thrown if a method needs to communicate with the device while the IP Connection is not connected.
Since Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.
The package for all Brick/Bricklet bindings and the IP Connection is com.tinkerforge.*
All methods listed below are thread-safe.
Creates an object with the unique device ID uid:
BrickletAmbientLight ambientLight = new BrickletAmbientLight("YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected (see examples above).
Returns the illuminance of the ambient light sensor. The value has a range of 0 to 9000 and is given in Lux/10, i.e. a value of 4500 means that an illuminance of 450 Lux is measured.
If you want to get the illuminance periodically, it is recommended to use the listener IlluminanceListener and set the period with setIlluminanceCallbackPeriod().
Returns the value as read by a 12-bit analog-to-digital converter. The value is between 0 and 4095.
Note
The value returned by getIlluminance() is averaged over several samples to yield less noise, while getAnalogValue() gives back raw unfiltered analog values. The only reason to use getAnalogValue() is, if you need the full resolution of the analog-to-digital converter.
Also, the analog-to-digital converter covers three different ranges that are set dynamically depending on the light intensity. It is impossible to distinguish between these ranges with the analog value.
If you want the analog value periodically, it is recommended to use the listener AnalogValueListener and set the period with setAnalogValueCallbackPeriod().
Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For listener configuration functions it is enabled by default too, but can be disabled by setResponseExpected(). For setter functions it is disabled by default and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.
See setResponseExpected() for the list of function ID constants available for this function.
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and listener configuration functions (default value: true). For getter functions it is always enabled and listeners it is always disabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.
The following function ID constants are available for this function:
Changes the response expected flag for all setter and listener configuration functions of this device at once.
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c' or 'd'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
The returned object has the public member variables String uid, String connectedUid, char position, short[] hardwareVersion, short[] firmwareVersion and int deviceIdentifier.
Sets the period in ms with which the IlluminanceListener listener is triggered periodically. A value of 0 turns the listener off.
IlluminanceListener is only triggered if the illuminance has changed since the last triggering.
The default value is 0.
Returns the period as set by setIlluminanceCallbackPeriod().
Sets the period in ms with which the AnalogValueListener listener is triggered periodically. A value of 0 turns the listener off.
AnalogValueListener is only triggered if the analog value has changed since the last triggering.
The default value is 0.
Returns the period as set by setAnalogValueCallbackPeriod().
Sets the thresholds for the IlluminanceReachedListener listener.
The following options are possible:
Option | Description |
---|---|
'x' | Listener is turned off |
'o' | Listener is triggered when the illuminance is outside the min and max values |
'i' | Listener is triggered when the illuminance is inside the min and max values |
'<' | Listener is triggered when the illuminance is smaller than the min value (max is ignored) |
'>' | Listener is triggered when the illuminance is greater than the min value (max is ignored) |
The default value is ('x', 0, 0).
The following constants are available for this function:
Returns the threshold as set by setIlluminanceCallbackThreshold().
The following constants are available for this function:
The returned object has the public member variables char option, short min and short max.
Sets the thresholds for the AnalogValueReachedListener listener.
The following options are possible:
Option | Description |
---|---|
'x' | Listener is turned off |
'o' | Listener is triggered when the analog value is outside the min and max values |
'i' | Listener is triggered when the analog value is inside the min and max values |
'<' | Listener is triggered when the analog value is smaller than the min value (max is ignored) |
'>' | Listener is triggered when the analog value is greater than the min value (max is ignored) |
The default value is ('x', 0, 0).
The following constants are available for this function:
Returns the threshold as set by setAnalogValueCallbackThreshold().
The following constants are available for this function:
The returned object has the public member variables char option, int min and int max.
Sets the period in ms with which the threshold listeners
are triggered, if the thresholds
keep being reached.
The default value is 100.
Returns the debounce period as set by setDebouncePeriod().
Listeners can be registered to receive time critical or recurring data from the device. The registration is done with "add*Listener" functions of the device object.
The parameter is a listener class object, for example:
device.addExampleListener(new BrickletAmbientLight.ExampleListener() {
public void property(int value) {
System.out.println("Value: " + value);
}
});
The available listener classes with inherent methods to be overwritten are described below. It is possible to add several listeners and to remove them with the corresponding "remove*Listener" function.
Note
Using listeners for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.
This listener can be added with the addIlluminanceListener() function. An added listener can be removed with the removeIlluminanceListener() function.
This listener is triggered periodically with the period that is set by setIlluminanceCallbackPeriod(). The parameter is the illuminance of the ambient light sensor.
IlluminanceListener is only triggered if the illuminance has changed since the last triggering.
This listener can be added with the addAnalogValueListener() function. An added listener can be removed with the removeAnalogValueListener() function.
This listener is triggered periodically with the period that is set by setAnalogValueCallbackPeriod(). The parameter is the analog value of the ambient light sensor.
AnalogValueListener is only triggered if the analog value has changed since the last triggering.
This listener can be added with the addIlluminanceReachedListener() function. An added listener can be removed with the removeIlluminanceReachedListener() function.
This listener is triggered when the threshold as set by setIlluminanceCallbackThreshold() is reached. The parameter is the illuminance of the ambient light sensor.
If the threshold keeps being reached, the listener is triggered periodically with the period as set by setDebouncePeriod().
This listener can be added with the addAnalogValueReachedListener() function. An added listener can be removed with the removeAnalogValueReachedListener() function.
This listener is triggered when the threshold as set by setAnalogValueCallbackThreshold() is reached. The parameter is the analog value of the ambient light sensor.
If the threshold keeps being reached, the listener is triggered periodically with the period as set by setDebouncePeriod().
This constant is used to identify a Ambient Light Bricklet.
The getIdentity() function and the EnumerateListener listener of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.