snmpinformrequest.java

Mobile 应用程序使用 Java Micro Edition (Java ME) 平台

     * Parses the inform response packet. If the agent responds with error set,
     * it does not parse any further.
     */
    synchronized void parsePduPacket(SnmpPduRequestType rpdu) {
        
        if (rpdu == null)
            return;
	
        errorStatus = rpdu.getErrorStatus();
        errorIndex = rpdu.getErrorIndex();
	
        if (errorStatus == snmpRspNoError) {
            updateInternalVarBindWithResult(((SnmpPdu)rpdu).varBindList);
            return;
        }
	
        if (errorStatus != snmpRspNoError)  
            --errorIndex;  // rationalize for index to start with 0.
	
        if (isTraceOn()) {
            trace("parsePduPacket", "received inform response. ErrorStatus/ErrorIndex = " + errorStatus + "/" + errorIndex);
        }
    }
    
    /**
     * Calls the user implementation of the <CODE>SnmpInformHandler</CODE> interface.
     */
    private void handleSuccess() {
        
        setRequestStatus(stResultsAvailable);

        if (isTraceOn()) {
            trace("handleSuccess", "Invoking user defined callback...");
        }

        deleteRequest();  // delete only non-poll request.
        notifyClient();
		
        requestPdu = null;
	//responsePdu = null;
        internalVarBind = null;

        try {  // catch all user exception which may happen in callback.
            if (callback != null)
                callback.processSnmpPollData(this, errorStatus, errorIndex, getVarBindList());
        } catch (Exception e) {
            if (isDebugOn()) {
                debug("handleSuccess", "Exception generated by user callback");
                debug("handleSuccess", e);
            }
        } catch (OutOfMemoryError ome) {
            if (isDebugOn()) {
                debug("handleSuccess", "OutOfMemory Error generated by user callback");
                debug("handleSuccess", ome);
            }
            Thread.currentThread().yield();
        }
        return;
    }

    /**
     * Calls the user implementation of the <CODE>SnmpInformHandler</CODE> interface.
     */
    private void handleTimeout() {
        
        setRequestStatus(stTimeout);
        
        if (isDebugOn()) {
            debug("handleTimeout", "Snmp error/index = " + snmpErrorToString(errorStatus) + "/" +
                  errorIndex + ". Invoking timeout user defined callback...");
        }
        deleteRequest();
        notifyClient();

        requestPdu = null;
	responsePdu = null;
        internalVarBind = null;

        try {
            if (callback != null) 
                callback.processSnmpPollTimeout(this);
        } catch (Exception e) {  // catch any exception a user might not handle.
            if (isDebugOn()) {
                debug("handleTimeout", "Exception generated by user callback");
                debug("handleTimeout", e);
            }
        } catch (OutOfMemoryError ome) {
            if (isDebugOn()) {
                debug("handleTimeout", "OutOfMemory Error generated by user callback");
                debug("handleTimeout", ome);
            }
            Thread.currentThread().yield();
        }
        return;
    }
  
    /**
     * Calls the user implementation of the <CODE>SnmpInformHandler</CODE> interface.
     */
    private void handleError(String msg) {
        
        setRequestStatus(stResultsAvailable);

        if (isDebugOn()) {
            debug("handleError", "Snmp error/index = " + snmpErrorToString(errorStatus) + "/" +
                  errorIndex + ". Invoking error user defined callback...\n" + getVarBindList());
        }
        deleteRequest();
        notifyClient();
		
        requestPdu = null;
	responsePdu = null;
        internalVarBind = null;
		
        try {
            if (callback != null)
                callback.processSnmpPollData(this, getErrorStatus(), getErrorIndex(), getVarBindList());
        } catch (Exception e) {  // catch any exception a user might not handle.
            if (isDebugOn()) {
                debug("handleError", "Exception generated by user callback");
                debug("handleError", e);
            }
        } catch (OutOfMemoryError ome) {
            if (isDebugOn()) {
                debug("handleError", "OutOfMemory Error generated by user callback");
                debug("handleError", ome);
            }
            Thread.currentThread().yield();
        }
    }

    /**
     * Calls the user implementation of the <CODE>SnmpInformHandler</CODE> interface.
     */
    private void handleInternalError(String msg) {
        
        setRequestStatus(stInternalError);
        if (reason == null)
            reason = msg;

        if (isDebugOn()) {
            debug("handleInternalError", "Snmp error/index = " + snmpErrorToString(errorStatus) + "/" +
                  errorIndex + ". Invoking internal error user defined callback...\n" + getVarBindList());
        }

        deleteRequest();
        notifyClient();

        requestPdu = null;
	responsePdu = null;
        internalVarBind = null;
		
        try {
            if (callback != null) 
                callback.processSnmpInternalError(this, reason);
        } catch (Exception e) {  // catch any exception a user might not handle.
            if (isDebugOn()) {
                debug("handleInternalError", "Exception generated by user callback");
                debug("handleInternalError", e);
            }
        } catch (OutOfMemoryError ome) {
            if (isDebugOn()) {
                debug("handleInternalError", "OutOfMemory Error generated by user callback");
                debug("handleInternalError", ome);
            }
            Thread.currentThread().yield();
        }
    }

    void updateInternalVarBindWithResult(SnmpVarBind[] list) {
     
        if ((list == null) || (list.length == 0))
            return;
    
        int idx = 0;
        
        for(int i = 0; i < internalVarBind.length && idx < list.length; i++) {
            SnmpVarBind avar = internalVarBind[i];
            if (avar == null)
                continue;
                
            SnmpVarBind res = list[idx];
            avar.setSnmpValue(res.getSnmpValue());
            idx++;
        }
    }
    
    /**
     * For SNMP Runtime internal use only.
     */
    final void invokeOnResponse(Object resp) {
        if (resp != null) {
            if (resp instanceof SnmpPduRequestType) 
                responsePdu = (SnmpPduRequestType) resp;
            else 
                return;
        }
        setRequestStatus(stReceivedReply);
        queueResponse();
    }
    
    /**
     * This method cancels an active inform request and removes it from the polling list.
     */
    private void stopRequest() {
        
        // Remove the clause synchronized of the stopRequest method.
        // Synchronization is isolated as possible to avoid thread lock.
        // Note: the method removeRequest from SendQ is synchronized.
        // fix bug jaw.00392.B
        //
        synchronized(this) {
            setRequestStatus(stAborted);
        }
        informSession.getSnmpQManager().removeRequest(this);
        synchronized(this) {
            requestId = 0;
        }
    }
    
    final synchronized void deleteRequest() {
        informSession.removeInformRequest(this);
    }
    
    /**
     * For SNMP Runtime internal use only.
     * Gets the active <CODE>SnmpVarBindList</CODE>. The contents of it
     * are not guaranteed to be consistent when the inform request is active.
     * @return The list of <CODE>SnmpVarBind</CODE> objects.
     */
    final synchronized SnmpVarBindList getVarBindList() {
        return varBindList;
    }

    /**
     * For SNMP Runtime internal use only.
     * You should specify the <CODE>SnmpVarBindList</CODE> at SnmpInformRequest creation time. 
     * You cannot modify it during the life-time of the object.
     */
    final synchronized void setVarBindList(SnmpVarBindList newvblst) {
        varBindList = newvblst;
        if (internalVarBind == null || internalVarBind.length != varBindList.size()) {
            internalVarBind = new SnmpVarBind[varBindList.size()];
        }
        varBindList.copyInto(internalVarBind);
    }

    /**
     * For SNMP Runtime internal use only.
     */
    final synchronized void setErrorStatusAndIndex(int stat, int idx) {
        errorStatus = stat;
        errorIndex = idx;
    }
    
    /**
     * For SNMP Runtime internal use only.
     */
    final synchronized void setPrevPollTime(long prev) {
        prevPollTime = prev;
    }

    /**
     * For SNMP Runtime internal use only.
     */
    final  void setRequestSentTime(long sendtime) {
        numTries++;
        setPrevPollTime(sendtime);
        waitTimeForResponse = prevPollTime + timeout*numTries;
        setRequestStatus(stWaitingForReply);
    
        if (isTraceOn()) {
            trace("setRequestSentTime", "Inform request Successfully sent");
        }
    
        informSession.getSnmpQManager().addWaiting(this);
    }

    /**
     * Initializes the request id from the request counter.
     */
    final synchronized void initNewRequest() {
        requestId = requestCounter.getNewId();
    }

    /**
     * For SNMP Runtime internal use only.
     */
    long timeRemainingForAction(long currtime) {
        switch (reqState) {
        case stWaitingToSend :
            return nextPollTime - currtime;
        case stWaitingForReply :
            return waitTimeForResponse - currtime;
        default :
            return -1;
        }
    }

    /**
     * Returns the string state corresponding to the specified integer state.
     * @param state The integer state.
     * @return The string state.
     */
    final static String statusDescription(int state) {
        switch (state) {
        case stWaitingToSend :
            return "Waiting to send.";
        case stWaitingForReply :
            return "Waiting for reply.";
        case stReceivedReply :
            return "Response arrived.";
        case stAborted  :
            return "Aborted by user.";
        case stTimeout :
            return "Timeout Occured.";
        case stInternalError :
            return "Internal error.";
        case stResultsAvailable :
            return "Results available";
        case stNeverUsed :
            return "Inform request in createAndWait state";
        }
        return "Unknown inform request state.";
    }

    /**
     * Sets the request status to the specified value.
     * @param reqst The new status request.
     */
    final synchronized void setRequestStatus(int reqst) {
        reqState = reqst;
    }

    /**
     * Gives a status report of the request.
     * @return The status report of the request.
     */
    public synchronized String toString() {
        StringBuffer s = new StringBuffer(300) ;
        s.append(tostring()) ;
        s.append("\nPeer/Port : " + address.getHostName() + "/" + port) ;

        return s.toString() ;
    }
    
    private synchronized String tostring() {
        StringBuffer s = new StringBuffer("InformRequestId = " + requestId);
        s.append("   " + "Status = " + statusDescription(reqState));
        s.append("  Timeout/MaxTries/NumTries = " + timeout*numTries + "/" +
                 + getMaxTries() + "/" + numTries);

        if (prevPollTime > 0) {
            debugDate.setTime(prevPollTime);
            s.append("\nPrevPolled = " + debugDate.toString());
        } else
            s.append("\nNeverPolled");
        s.append(" / RemainingTime(millis) = " + 
                 timeRemainingForAction(System.currentTimeMillis()));

        return s.toString();
    }

    // TRACES & DEBUG
    //---------------
    
    boolean isTraceOn() {
        return Trace.isSelected(Trace.LEVEL_TRACE, Trace.INFO_ADAPTOR_SNMP);
    }

    void trace(String clz, String func, String info) {
        Trace.send(Trace.LEVEL_TRACE, Trace.INFO_ADAPTOR_SNMP, clz, func, info);
    }

    void trace(String func, String info) {
        trace(dbgTag, func, info);
    }
    
    boolean isDebugOn() {
        return Trace.isSelected(Trace.LEVEL_DEBUG, Trace.INFO_ADAPTOR_SNMP);
    }

    void debug(String clz, String func, String info) {
        Trace.send(Trace.LEVEL_DEBUG, Trace.INFO_ADAPTOR_SNMP, clz, func, info);
    }

    void debug(String clz, String func, Throwable exception) {
        Trace.send(Trace.LEVEL_DEBUG, Trace.INFO_ADAPTOR_SNMP, clz, func, exception);
    }
    
    void debug(String func, String info) {
        debug(dbgTag, func, info);
    }
    
    void debug(String func, Throwable exception) {
        debug(dbgTag, func, exception);
    }
    
}