I have a simple rule that is kicking our an Error, but it looks like it is executing correctly to me.
2016-05-14 18:01:04.003 [ERROR] [o.o.c.s.ScriptExecutionThread ] - Error during the execution of rule 'Hydrogen_Peroxide_Sensor'
My rule:
import javax.xml.bind.DatatypeConverter
import java.nio.*
import java.lang.*
import org.openhab.core.library.types.*
rule "Ping Sensors"
when
Time cron "0/2 * * * * ?"
then
logInfo("Hydrogen", "Pinging Sensors")
sendCommand(Hydrogen_Peroxide_Sensor, '\u0055')
end
rule "Hydrogen_Peroxide_Sensor"
when
Item Hydrogen_Peroxide_Sensor received update
then
val to64 = DatatypeConverter::parseBase64Binary(Hydrogen_Peroxide_Sensor.state.toString)
val ByteBuffer bb = ByteBuffer::wrap(to64)
val short distance = bb.getShort
logInfo("Hydrogen", "Distance: " + distance)
end
Not sure that’s it, If I take out the loginfo I still get the error:
2016-05-16 09:10:45.004 [ERROR] [o.o.c.s.ScriptExecutionThread ] - Error during the execution of rule 'Hydrogen_Peroxide_Sensor'
java.nio.BufferUnderflowException: null
at java.nio.Buffer.nextGetIndex(Buffer.java:506) ~[na:1.8.0_66]
at java.nio.HeapByteBuffer.getShort(HeapByteBuffer.java:310) ~[na:1.8.0_66]
at sun.reflect.GeneratedMethodAccessor75.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.invokeOperation(XbaseInterpreter.java:729) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._featureCallOperation(XbaseInterpreter.java:713) ~[na:na]
at sun.reflect.GeneratedMethodAccessor45.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.openhab.model.script.interpreter.ScriptInterpreter.internalFeatureCallDispatch(ScriptInterpreter.java:69) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateMemberFeatureCall(XbaseInterpreter.java:549) ~[na:na]
at sun.reflect.GeneratedMethodAccessor47.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateVariableDeclaration(XbaseInterpreter.java:601) ~[na:na]
at sun.reflect.GeneratedMethodAccessor74.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateBlockExpression(XbaseInterpreter.java:321) ~[na:na]
at sun.reflect.GeneratedMethodAccessor78.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.evaluate(XbaseInterpreter.java:204) ~[na:na]
at org.openhab.model.script.internal.engine.ScriptImpl.execute(ScriptImpl.java:59) ~[na:na]
at org.openhab.core.scriptengine.ScriptExecutionThread.run(ScriptExecutionThread.java:44) ~[na:na]
Sadly the best way I’ve found is to just add a logging statement every other line and see which line in the rule immediately precedes the error.
The “BufferUnderflowException” points to the val short distance = bb.getShort line. A buffer underflow happens when there are not enough bytes to create the primitive asked for. In this case a short is two bytes so to64 must be one byte or less.
If you are only expecting one byte, you might need to use val byte distance = bb.getByte. I think you can treat a byte as a number so you should be able to print it and do math with it as if it were a short.
Was driving me crazy because I know the response from the sensor is two bytes. However, to ping the sensor you send 0x55 and that is just one byte that is also received by my rule.
import javax.xml.bind.DatatypeConverter
import java.nio.*
import java.lang.*
import org.openhab.core.library.types.*
rule "Ping Sensors"
when
Time cron "0/5 * * * * ?"
then
sendCommand(Hydrogen_Peroxide_Sensor, '\u0055')
end
rule "Hydrogen_Peroxide_Sensor"
when
Item Hydrogen_Peroxide_Sensor received update
then
val to64 = DatatypeConverter::parseBase64Binary(Hydrogen_Peroxide_Sensor.state.toString)
val ByteBuffer bb = ByteBuffer::wrap(to64)
logInfo("Hydrogen", "bb: " + bb)
val short distance = bb.getShort
logInfo("Hydrogen", "Distance: " + distance)
end
So I guess my questions are; first should I be using something other then “sendCommand” and “received update” so that I don’t see the 0x55 I am sending come into my rule as a single byte? If not, is there a clean way to execute “val short distance = bb.getShort” only if there are two bytes?
Log:
2016-05-16 12:43:10.002 [INFO ] [.openhab.model.script.Hydrogen] - bb: java.nio.HeapByteBuffer[pos=0 lim=0 cap=0]
2016-05-16 12:43:10.002 [INFO ] [runtime.busevents ] - Hydrogen_Peroxide_Sensor received command U
2016-05-16 12:43:10.003 [ERROR] [o.o.c.s.ScriptExecutionThread ] - Error during the execution of rule 'Hydrogen_Peroxide_Sensor'
java.nio.BufferUnderflowException: null
at java.nio.Buffer.nextGetIndex(Buffer.java:506) ~[na:1.8.0_66]
at java.nio.HeapByteBuffer.getShort(HeapByteBuffer.java:310) ~[na:1.8.0_66]
at sun.reflect.GeneratedMethodAccessor75.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.invokeOperation(XbaseInterpreter.java:729) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._featureCallOperation(XbaseInterpreter.java:713) ~[na:na]
at sun.reflect.GeneratedMethodAccessor45.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.openhab.model.script.interpreter.ScriptInterpreter.internalFeatureCallDispatch(ScriptInterpreter.java:69) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateMemberFeatureCall(XbaseInterpreter.java:549) ~[na:na]
at sun.reflect.GeneratedMethodAccessor47.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateVariableDeclaration(XbaseInterpreter.java:601) ~[na:na]
at sun.reflect.GeneratedMethodAccessor74.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter._evaluateBlockExpression(XbaseInterpreter.java:321) ~[na:na]
at sun.reflect.GeneratedMethodAccessor78.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.eclipse.xtext.util.PolymorphicDispatcher.invoke(PolymorphicDispatcher.java:291) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.internalEvaluate(XbaseInterpreter.java:218) ~[na:na]
at org.eclipse.xtext.xbase.interpreter.impl.XbaseInterpreter.evaluate(XbaseInterpreter.java:204) ~[na:na]
at org.openhab.model.script.internal.engine.ScriptImpl.execute(ScriptImpl.java:59) ~[na:na]
at org.openhab.core.scriptengine.ScriptExecutionThread.run(ScriptExecutionThread.java:44) ~[na:na]
2016-05-16 12:43:10.224 [INFO ] [runtime.busevents ] - Hydrogen_Peroxide_Sensor state updated to CO+/vQ==
2016-05-16 12:43:10.226 [INFO ] [.openhab.model.script.Hydrogen] - bb: java.nio.HeapByteBuffer[pos=0 lim=4 cap=4]
2016-05-16 12:43:10.226 [INFO ] [.openhab.model.script.Hydrogen] - Distance: 2287
