Unsolvable error with multiple requested values send to the plc (apache.plc4x)

Question

I'm new here and my first question is regarding the request of PLC values, using Apache PLC4x. I want to loop through all the actual I, Q and DB available in the PLC. Because I want not able to accomplish this I looped through a set of DB but if the DB is not reachable it just prints out "Error processing message".

Is looping through all the entities possible?

By try and error I found some reachable DB but wasn't able to loop through all the available data.

Thank you!

---

for (int m = 1; m < 10; m++) {

 for (int j = 1; j < 9; j++) {

  readBuilder.addItem("value_int " + m + "." + j, "%DB" + m + "." + "DB" + j + ":INT");

 }

}

Error message:

[nioEventLoopGroup-2-1] ERROR org.apache.plc4x.java.s7.netty.S7Protocol - Error processing message
java.lang.IndexOutOfBoundsException: Index: 107, Size: 107
at java.util.LinkedList.checkElementIndex(Unknown Source)
at java.util.LinkedList.get(Unknown Source)
at org.apache.plc4x.java.s7.netty.strategies.DefaultS7MessageProcessor.getMergedResponseMessage(DefaultS7MessageProcessor.java:418)
at org.apache.plc4x.java.s7.netty.strategies.DefaultS7MessageProcessor.processResponse(DefaultS7MessageProcessor.java:346)
at org.apache.plc4x.java.s7.netty.S7Protocol.decode(S7Protocol.java:483)
at org.apache.plc4x.java.s7.netty.S7Protocol$1.decode(S7Protocol.java:86)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:88)
at org.apache.plc4x.java.s7.netty.S7Protocol.channelRead(S7Protocol.java:416)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102)
at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:310)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:284)
at io.netty.handler.codec.ByteToMessageCodec.channelRead(ByteToMessageCodec.java:103)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1408)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:930)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:163)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:682)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:617)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:534)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:496)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:906)
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Unknown Source)
[nioEventLoopGroup-2-1] WARN io.netty.channel.DefaultChannelPipeline - An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.
java.lang.IndexOutOfBoundsException: Index: 107, Size: 107
at java.util.LinkedList.checkElementIndex(Unknown Source)
at java.util.LinkedList.get(Unknown Source)
at org.apache.plc4x.java.s7.netty.strategies.DefaultS7MessageProcessor.`getMergedResponseMessage`(DefaultS7MessageProcessor.java:418)
at org.apache.plc4x.java.s7.netty.strategies.DefaultS7MessageProcessor.processResponse(DefaultS7MessageProcessor.java:346)
at org.apache.plc4x.java.s7.netty.S7Protocol.decode(S7Protocol.java:483)
at org.apache.plc4x.java.s7.netty.S7Protocol$1.decode(S7Protocol.java:86)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:88)
at org.apache.plc4x.java.s7.netty.S7Protocol.channelRead(S7Protocol.java:416)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102)
at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:310)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:284)
at io.netty.handler.codec.ByteToMessageCodec.channelRead(ByteToMessageCodec.java:103)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1408)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:374)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:360)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:930)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:163)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:682)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:617)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:534)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:496)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:906)
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Unknown Source)

'''

Answer 1

sorry for not replying sooner ... I simply forgot. We currently don't have StackOverflow on our radar to prominently, but we'll try to improve this.

We have found the problem and have fixed it. Also a new version of Apache PLC4X has been released to address this (Version 0.5.0). Please give this version a try.

Reference to the bug report we created for your issue https://issues.apache.org/jira/browse/PLC4X-144

Hope this helps.