Hessian2ObjectInput.readObject : hessian 反序列化空指针异常

阳光穿透心脏的1/2处 2022-05-12 14:34 196阅读 0赞

java.lang.NullPointerException
    	at sun.reflect.GeneratedConstructorAccessor329.newInstance(Unknown Source)
    	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    	at com.alibaba.com.caucho.hessian.io.JavaDeserializer.instantiate(JavaDeserializer.java:312)
    	at com.alibaba.com.caucho.hessian.io.JavaDeserializer.readObject(JavaDeserializer.java:201)
    	at com.alibaba.com.caucho.hessian.io.SerializerFactory.readObject(SerializerFactory.java:526)
    	at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObjectInstance(Hessian2Input.java:2810)
    	at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2750)
    	at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2279)
    	at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2724)
    	at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:2279)
    	at com.alibaba.dubbo.common.serialize.hessian2.Hessian2ObjectInput.readObject(Hessian2ObjectInput.java:84)
    	at com.alibaba.dubbo.rpc.protocol.dubbo.DecodeableRpcResult.decode(DecodeableRpcResult.java:92)
    	at com.alibaba.dubbo.rpc.protocol.dubbo.DecodeableRpcResult.decode(DecodeableRpcResult.java:113)
    	at com.alibaba.dubbo.rpc.protocol.dubbo.DubboCodec.decodeBody(DubboCodec.java:89)
    	at com.alibaba.dubbo.remoting.exchange.codec.ExchangeCodec.decode(ExchangeCodec.java:124)
    	at com.alibaba.dubbo.remoting.exchange.codec.ExchangeCodec.decode(ExchangeCodec.java:84)
    	at com.alibaba.dubbo.rpc.protocol.dubbo.DubboCountCodec.decode(DubboCountCodec.java:46)
    	at com.alibaba.dubbo.remoting.transport.netty.NettyCodecAdapter$InternalDecoder.messageReceived(NettyCodecAdapter.java:133)
    	at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:75)
    	at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:565)
    	at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:560)
    	at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
    	at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
    	at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:84)
    	at org.jboss.netty.channel.socket.nio.AbstractNioWorker.processSelectedKeys(AbstractNioWorker.java:465)
    	at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:332)
    	at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:35)
    	at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:102)
    	at org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
    	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    	at java.lang.Thread.run(Thread.java:745)

问题描述：

dubbo服务在进行服务间的远程调用时，通过hessain进行对象的序列化；出现了反序列化异常；

思路：

hessain反序列化异常有几种场景：

1. 两个jar中所引用的某个对象不是同一个导致，比如：对象A，之前有字段 name,sex, 后面将A对象加入age字段，而反序列化所在的服务中所引用的jar包还是旧的A对象，没有age字段，导致对象反序列化失败（此种情况一般会直接提示那个对象反序列失败）；

2. dubbo服务提供者和消费者版本不对，会导致反序列化失败；类似于1；

3. 就是上面说的这种；调用其他的服务，被调用的服务底层出现了空指针异常，导致异常往上抛； 此时建议排查反序列化失败的这个方法调用的方法栈，依次排查被调用的服务是否存在错误日志；