GATTCharacteristic: Add enableNotificationOrIndication(..)..; DIRECTBT_CHARACTERISTIC_VALUE_CACHE_NOTIFICATION_COMPATv2.1.15

GATTCharacteristic (Java/C++): Add enableNotificationOrIndication(..) and use it as default for BLE active addCharacteristicListener(..).

It is recommended to utilize notification over indication, as its link-layer handshake
and higher potential bandwidth may deliver material higher performance.

+++

Add setting BluetoothFactory.DIRECTBT_CHARACTERISTIC_VALUE_CACHE_NOTIFICATION_COMPAT
(and also document DEBUG and VERBOSE).

DIRECTBT_CHARACTERISTIC_VALUE_CACHE_NOTIFICATION_COMPAT

Have direct_bt provide compatibility to TinyB's BluetoothGattCharacteristic
API: BluetoothGattCharacteristic#getValue() value cache and
BluetoothGattCharacteristic#enableValueNotifications(BluetoothNotification) value notification.

DBTGattCharacteristic benefits from _disabled_ compatibility (and DEBUG)
performance wise, as no listener nor cache needs to be added in this case!

1 files changed, 3 insertions, 0 deletions

diff --git a/examples/java/ScannerTinyB10.java b/examples/java/ScannerTinyB10.java
index 78235138..0a9b3114 100644
--- a/examples/java/ScannerTinyB10.java
+++ b/examples/java/ScannerTinyB10.java
@@ -416,6 +416,9 @@ public class ScannerTinyB10 {
                 System.setProperty("org.tinyb.verbose", "true");
             }
         }
+        // Drop BluetoothGattCharacteristic value cache and notification compatibility using direct_bt.
+        System.setProperty("direct_bt.tinyb.characteristic.compat", "false");
+
         if( null == bluetoothManagerClazzName ) {
             bluetoothManagerClazzName = BluetoothFactory.DirectBTImplementationID.BluetoothManagerClassName;
         }