Program: 107020
Project: 107020
Buggy source:
@Override protected void doTask(final Task task) throws Exception {
  Transaction txn=Transaction.open(Transaction.CLOUD_DB);
  try {
    if (task.getType() != Task.Type.DATA) {
      super.doTask(task);
      return;
    }
    final byte[] data=task.getData();
    Version ver=Request.getVersion(data);
    if (ver.ordinal() != Version.v1.ordinal()) {
      s_logger.warn("String_Node_Str");
      super.doTask(task);
      return;
    }
    long hostId=Request.getAgentId(data);
    Link link=task.getLink();
    if (Request.fromServer(data)) {
      AgentAttache agent=findAttache(hostId);
      if (Request.isControl(data)) {
        if (agent == null) {
          logD(data,"String_Node_Str");
          return;
        }
        Request req=Request.parse(data);
        Command[] cmds=req.getCommands();
        CancelCommand cancel=(CancelCommand)cmds[0];
        if (s_logger.isDebugEnabled()) {
          logD(data,"String_Node_Str");
        }
        agent.cancel(cancel.getSequence());
        return;
      }
      try {
        if (agent == null || agent.isClosed()) {
          throw new AgentUnavailableException("String_Node_Str",hostId);
        }
        if (Request.isRequest(data) && Request.requiresSequentialExecution(data)) {
          Request req=Request.parse(data);
          agent.send(req,null);
          return;
        }
 else {
          if (agent instanceof Routable) {
            Routable cluster=(Routable)agent;
            cluster.routeToAgent(data);
          }
 else {
            agent.send(Request.parse(data));
          }
          return;
        }
      }
 catch (      AgentUnavailableException e) {
        logD(data,e.getMessage());
        cancel(Long.toString(Request.getManagementServerId(data)),hostId,Request.getSequence(data),e.getMessage());
      }
    }
 else {
      long mgmtId=Request.getManagementServerId(data);
      if (mgmtId != -1 && mgmtId != _nodeId) {
        routeToPeer(Long.toString(mgmtId),data);
        if (Request.requiresSequentialExecution(data)) {
          AgentAttache attache=(AgentAttache)link.attachment();
          if (attache != null) {
            attache.sendNext(Request.getSequence(data));
          }
 else           if (s_logger.isDebugEnabled()) {
            logD(data,"String_Node_Str" + Request.parse(data).toString());
          }
        }
        return;
      }
 else {
        if (Request.isRequest(data)) {
          super.doTask(task);
        }
 else {
          final Response response=Response.parse(data);
          AgentAttache attache=findAttache(response.getAgentId());
          if (attache == null) {
            s_logger.info("String_Node_Str" + response.getAgentId() + "String_Node_Str"+ response.getSequence()+ "String_Node_Str"+ response.toString());
            return;
          }
          if (!attache.processAnswers(response.getSequence(),response)) {
            s_logger.info("String_Node_Str" + attache.getId() + "String_Node_Str"+ response.getSequence()+ "String_Node_Str"+ response.toString());
          }
        }
        return;
      }
    }
  }
  finally {
    txn.close();
  }
}

Fixed version (ground truth):
@Override protected void doTask(final Task task) throws Exception {
  Transaction txn=Transaction.open(Transaction.CLOUD_DB);
  try {
    if (task.getType() != Task.Type.DATA) {
      super.doTask(task);
      return;
    }
    final byte[] data=task.getData();
    Version ver=Request.getVersion(data);
    if (ver.ordinal() != Version.v1.ordinal() && ver.ordinal() != Version.v3.ordinal()) {
      s_logger.warn("String_Node_Str");
      super.doTask(task);
      return;
    }
    long hostId=Request.getAgentId(data);
    Link link=task.getLink();
    if (Request.fromServer(data)) {
      AgentAttache agent=findAttache(hostId);
      if (Request.isControl(data)) {
        if (agent == null) {
          logD(data,"String_Node_Str");
          return;
        }
        Request req=Request.parse(data);
        Command[] cmds=req.getCommands();
        CancelCommand cancel=(CancelCommand)cmds[0];
        if (s_logger.isDebugEnabled()) {
          logD(data,"String_Node_Str");
        }
        agent.cancel(cancel.getSequence());
        return;
      }
      try {
        if (agent == null || agent.isClosed()) {
          throw new AgentUnavailableException("String_Node_Str",hostId);
        }
        if (Request.isRequest(data) && Request.requiresSequentialExecution(data)) {
          Request req=Request.parse(data);
          agent.send(req,null);
          return;
        }
 else {
          if (agent instanceof Routable) {
            Routable cluster=(Routable)agent;
            cluster.routeToAgent(data);
          }
 else {
            agent.send(Request.parse(data));
          }
          return;
        }
      }
 catch (      AgentUnavailableException e) {
        logD(data,e.getMessage());
        cancel(Long.toString(Request.getManagementServerId(data)),hostId,Request.getSequence(data),e.getMessage());
      }
    }
 else {
      long mgmtId=Request.getManagementServerId(data);
      if (mgmtId != -1 && mgmtId != _nodeId) {
        routeToPeer(Long.toString(mgmtId),data);
        if (Request.requiresSequentialExecution(data)) {
          AgentAttache attache=(AgentAttache)link.attachment();
          if (attache != null) {
            attache.sendNext(Request.getSequence(data));
          }
 else           if (s_logger.isDebugEnabled()) {
            logD(data,"String_Node_Str" + Request.parse(data).toString());
          }
        }
        return;
      }
 else {
        if (Request.isRequest(data)) {
          super.doTask(task);
        }
 else {
          final Response response=Response.parse(data);
          AgentAttache attache=findAttache(response.getAgentId());
          if (attache == null) {
            s_logger.info("String_Node_Str" + response.getAgentId() + "String_Node_Str"+ response.getSequence()+ "String_Node_Str"+ response.toString());
            return;
          }
          if (!attache.processAnswers(response.getSequence(),response)) {
            s_logger.info("String_Node_Str" + attache.getId() + "String_Node_Str"+ response.getSequence()+ "String_Node_Str"+ response.toString());
          }
        }
        return;
      }
    }
  }
  finally {
    txn.close();
  }
}