我正在开发一个基于smpp的应用程序。但是，我在解码smpp PDU时注意到了一些东西。当应用程序一次又一次收到少量pdu时，解码不会产生任何问题。但是，当它大量异步接收pdus时，我遇到了一些Nullpointer异常。这就是为什么我在ntty 3.X中没有问题，但是在净额中。我怀疑解码速度慢于即将到来的pdu速率，或者我错过了一些东西。
例外：
.............
c.c.smpp.channel.SmppPduReader -
io.netty.handler.codec.DecoderException: java.lang.NullPointerException: element
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:263) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:131) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at com.cloudhopper.smpp.channel.SmppChannelLogger.channelRead(SmppChannelLogger.java:63) ~[bin/:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:100) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:480) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:447) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:341) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101) ~[netty-all-4.0.10.Final.jar:na]
at java.lang.Thread.run(Thread.java:724) ~[na:1.7.0_25]
Caused by: java.lang.NullPointerException: element
at io.netty.util.internal.RecyclableArrayList.add(RecyclableArrayList.java:104) ~[netty-all-4.0.10.Final.jar:na]
at com.cloudhopper.smpp.channel.SmppPduDecoder.decode(SmppPduDecoder.java:42) ~[bin/:na]
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:232) ~[netty-all-4.0.10.Final.jar:na]
... 16 common frames omitted
c.c.s.i.GenericSmppSessionHandler - Default handling is to discard an unknown throwable:
io.netty.handler.codec.DecoderException: java.lang.NullPointerException: element
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:263) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:131) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at com.cloudhopper.smpp.channel.SmppChannelLogger.channelRead(SmppChannelLogger.java:63) ~[bin/:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.ChannelInboundHandlerAdapter.channelRead(ChannelInboundHandlerAdapter.java:86) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [netty-all-4.0.10.Final.jar:na]
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:100) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:480) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:447) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:341) ~[netty-all-4.0.10.Final.jar:na]
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101) ~[netty-all-4.0.10.Final.jar:na]
at java.lang.Thread.run(Thread.java:724) ~[na:1.7.0_25]
Caused by: java.lang.NullPointerException: element
at io.netty.util.internal.RecyclableArrayList.add(RecyclableArrayList.java:104) ~[netty-all-4.0.10.Final.jar:na]
at com.cloudhopper.smpp.channel.SmppPduDecoder.decode(SmppPduDecoder.java:42) ~[bin/:na]
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:232) ~[netty-all-4.0.10.Final.jar:na]
... 16 common frames omitted
public class SmppPduDecoder extends ByteToMessageDecoder {private final SmppPduTranscoder transcoder;
@SuppressWarnings("unused")
private static final Logger logger = LoggerFactory.getLogger(SmppPduDecoder.class);
/**
*
*/
public SmppPduDecoder(SmppPduTranscoder transcoder) {
this.transcoder = transcoder;
}
/* (non-Javadoc)
* @see io.netty.handler.codec.ByteToMessageDecoder#decode(io.netty.channel.ChannelHandlerContext, io.netty.buffer.ByteBuf, java.util.List)
*/
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in,
List<Object> out) throws Exception {
Pdu pdu = this.transcoder.decode(in);
out.add(pdu);
}
}
这是进行解码的代码转换器代码段。
@Override
public Pdu decode(ByteBuf buffer) throws UnrecoverablePduException, RecoverablePduException {
// wait until the length prefix is available
if (buffer.readableBytes() < SmppConstants.PDU_INT_LENGTH) {
return null;
}
// parse the command length (first 4 bytes)
int commandLength = buffer.getInt(buffer.readerIndex());
//logger.trace("PDU commandLength [" + commandLength + "]");
// valid command length is >= 16 bytes
if (commandLength < SmppConstants.PDU_HEADER_LENGTH) {
throw new UnrecoverablePduException("Invalid PDU length [0x" + HexUtil.toHexString(commandLength) + "] parsed");
}
// wait until the whole pdu is available (entire pdu)
if (buffer.readableBytes() < commandLength) {
return null;
}
// at this point, we have the entire PDU and length already in the buffer
// we'll create a new "view" of this PDU and read the data from the actual buffer
// NOTE: this should be super fast since the underlying byte array doesn't get copied
ByteBuf buffer0 = buffer.readSlice(commandLength);
return doDecode(commandLength, buffer0);
}
protected Pdu doDecode(int commandLength, ByteBuf buffer) throws UnrecoverablePduException, RecoverablePduException {
// skip the length field because we already parsed it
buffer.skipBytes(SmppConstants.PDU_INT_LENGTH);
// read the remaining portion of the PDU header
int commandId = buffer.readInt();
int commandStatus = buffer.readInt();
int sequenceNumber = buffer.readInt();
// this is a major issue if the sequence number is invalid
SequenceNumber.assertValid(sequenceNumber);
Pdu pdu = null;
// any command id with its 31st bit set to true is a response
if (PduUtil.isRequestCommandId(commandId)) {
if (commandId == SmppConstants.CMD_ID_ENQUIRE_LINK) {
pdu = new EnquireLink();
} else if (commandId == SmppConstants.CMD_ID_DELIVER_SM) {
pdu = new DeliverSm();
} else if (commandId == SmppConstants.CMD_ID_SUBMIT_SM) {
pdu = new SubmitSm();
} else if (commandId == SmppConstants.CMD_ID_DATA_SM) {
pdu = new DataSm();
} else if (commandId == SmppConstants.CMD_ID_CANCEL_SM) {
pdu = new CancelSm();
} else if (commandId == SmppConstants.CMD_ID_QUERY_SM) {
pdu = new QuerySm();
} else if (commandId == SmppConstants.CMD_ID_BIND_TRANSCEIVER) {
pdu = new BindTransceiver();
} else if (commandId == SmppConstants.CMD_ID_BIND_TRANSMITTER) {
pdu = new BindTransmitter();
} else if (commandId == SmppConstants.CMD_ID_BIND_RECEIVER) {
pdu = new BindReceiver();
} else if (commandId == SmppConstants.CMD_ID_UNBIND) {
pdu = new Unbind();
} else {
pdu = new PartialPdu(commandId);
}
} else {
if (commandId == SmppConstants.CMD_ID_SUBMIT_SM_RESP) {
pdu = new SubmitSmResp();
} else if (commandId == SmppConstants.CMD_ID_DELIVER_SM_RESP) {
pdu = new DeliverSmResp();
} else if (commandId == SmppConstants.CMD_ID_DATA_SM_RESP) {
pdu = new DataSmResp();
} else if (commandId == SmppConstants.CMD_ID_CANCEL_SM_RESP) {
pdu = new CancelSmResp();
} else if (commandId == SmppConstants.CMD_ID_QUERY_SM_RESP) {
pdu = new QuerySmResp();
} else if (commandId == SmppConstants.CMD_ID_ENQUIRE_LINK_RESP) {
pdu = new EnquireLinkResp();
} else if (commandId == SmppConstants.CMD_ID_BIND_TRANSCEIVER_RESP) {
pdu = new BindTransceiverResp();
} else if (commandId == SmppConstants.CMD_ID_BIND_RECEIVER_RESP) {
pdu = new BindReceiverResp();
} else if (commandId == SmppConstants.CMD_ID_BIND_TRANSMITTER_RESP) {
pdu = new BindTransmitterResp();
} else if (commandId == SmppConstants.CMD_ID_UNBIND_RESP) {
pdu = new UnbindResp();
} else if (commandId == SmppConstants.CMD_ID_GENERIC_NACK) {
pdu = new GenericNack();
} else {
pdu = new PartialPduResp(commandId);
}
}
// set pdu header values
pdu.setCommandLength(commandLength);
pdu.setCommandStatus(commandStatus);
pdu.setSequenceNumber(sequenceNumber);
// check if we need to throw an exception
if (pdu instanceof PartialPdu) {
throw new UnknownCommandIdException(pdu, "Unsupported or unknown PDU request commandId [0x" + HexUtil.toHexString(commandId) + "]");
} else if (pdu instanceof PartialPduResp) {
throw new UnknownCommandIdException(pdu, "Unsupported or unknown PDU response commandId [0x" + HexUtil.toHexString(commandId) + "]");
}
// see if we can map the command status into a message
if (pdu instanceof PduResponse) {
PduResponse response = (PduResponse)pdu;
response.setResultMessage(context.lookupResultMessage(commandStatus));
}
try {
// parse pdu body parameters (may throw exception)
pdu.readBody(buffer);
// parse pdu optional parameters (may throw exception)
pdu.readOptionalParameters(buffer, context);
} catch (RecoverablePduException e) {
// check if we should add the partial pdu to the exception
if (e.getPartialPdu() == null) {
e.setPartialPdu(pdu);
}
// rethrow it
throw e;
}
return pdu;
}
请Netty极客帮助我。
最佳答案
好像您要向结果列表添加null对象：
受保护的无效解码（ChannelHandlerContext ctx，ByteBuf in，
列出）抛出异常{
Pdu pdu = this.transcoder.decode（in）;
out.add（pdu）;
}
只需添加检查pdu是否不为空：
if (pdu != null) out.add(pdu);
关于java - Netty 4解码器问题，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/19291151/