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java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()	at android.os.Handler.(Handler.java:121)	at android.bluetooth.BluetoothAdapter$1.(BluetoothAdapter.java:1012)	at android.bluetooth.BluetoothAdapter.(BluetoothAdapter.java:1012)	at android.bluetooth.BluetoothAdapter.getDefaultAdapter(BluetoothAdapter.java:340)	at lejos.pc.comm.NXTCommAndroid.search(NXTCommAndroid.java:394)	at lejos.pc.comm.NXTConnector.search(NXTConnector.java:171)	at lejos.pc.comm.NXTConnector.connectTo(NXTConnector.java:222)	at lejos.pc.comm.NXTConnector.connectTo(NXTConnector.java:39)	at lejos.pc.comm.NXTCommandConnector.open(NXTCommandConnector.java:22)	at lejos.pc.comm.NXTCommandConnector.getSingletonOpen(NXTCommandConnector.java:41)	at lejos.nxt.Motor.(Motor.java:15)	at org.ros.android.tutorial.pubsub.NXTNode.onStart(NXTNode.java:239)	at org.ros.internal.node.DefaultNode$1.run(DefaultNode.java:422)	at org.ros.internal.node.DefaultNode$1.run(DefaultNode.java:419)	at org.ros.concurrent.ListenerCollection$1.run(ListenerCollection.java:108)	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088)	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581)	at java.lang.Thread.run(Thread.java:1019)