snmpmibgroup.java

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

        // registers the arc in the hashtable.
	subgroups.put(obj,obj);
    }

    // -------------------------------------------------------------------
    // The SnmpMibOid algorithm relies on the fact that for every arc 
    // registered in varList, there is a corresponding node at the same 
    // position in children.
    // So the trick is to register a null node in children for each variable
    // in varList, so that the real subgroup nodes can be inserted at the 
    // correct location. 
    // registerObject() should be called for each scalar object and each 
    // table arc by the generated subclass.
    /**
     * Register an OID arc that identifies a scalar object or a table.
     * This method is used internally. You shouldn't ever call it directly.
     *
     * @param arc An OID arc.
     *
     */
    protected void registerObject(long arc) 
	throws IllegalAccessException {

        // this will register the variable in both varList and children
        // The node registered in children will be null, so that the parent
        // algorithm will behave as if no node were registered. This is a
        // trick that makes the parent algorithm behave as if only subgroups
        // were registered in varList and children.
	long[] oid = new long[1];
	oid[0] = arc;
	super.registerNode(oid,0,null);
    }

    // -------------------------------------------------------------------
    // registerNode() will be called at runtime when nested groups are
    // registered in the MIB. So we do know that this method will only
    // be called to register nested-groups.
    // We trap registerNode() in order to call registerSubArc()
    /**
     * Register a child node of this node in the OID tree.
     * This method is used internally. You shouldn't ever call it directly.
     *
     * @param oid The oid of the node being registered.
     * @param cursor The position reached in the oid.
     * @param node The node being registered.
     *
     */
    void registerNode(long[] oid, int cursor ,SnmpMibNode node) 
	throws IllegalAccessException {
	super.registerNode(oid,cursor,node);
	if (cursor < 0) return;
	if (cursor >= oid.length) return;
        // if we get here, then it means we are registering a subgroup.
        // We will thus register the sub arc in the subgroups hashtable.
	registerNestedArc(oid[cursor]);
    }
    
    // -------------------------------------------------------------------
    // see comments in SnmpMibNode
    // -------------------------------------------------------------------
    void findHandlingNode(SnmpVarBind varbind, 
			  long[] oid, int depth, 
			  SnmpRequestTree handlers) 
	throws SnmpStatusException {

	int length = oid.length;
	SnmpMibNode node = null;
	
	if (handlers == null)
            throw new SnmpStatusException(SnmpStatusException.snmpRspGenErr);

	final Object data = handlers.getUserData();

	if (depth >= length) {
	    // Nothing is left... the oid is not valid
            throw new SnmpStatusException(SnmpStatusException.noAccess);
	}

	long arc = oid[depth];

	if (isNestedArc(arc)) {
	    // This arc leads to a subgroup: delegates the search to the
	    // method defined in SnmpMibOid
	    super.findHandlingNode(varbind,oid,depth,handlers);
	    return;
	} else if (isTable(arc)) {
	    // This arc leads to a table: forward the search to the table.
	    
	    // Gets the table
	    SnmpMibTable table = getTable(arc);
	    
	    // Forward the search to the table
	    table.findHandlingNode(varbind,oid,depth+1,handlers);

	} else {
	    // If it's not a variable, throws an exception
	    validateVarId(arc, data);

	    // The trailing .0 is missing in the OID
	    if (depth+2 > length)
		throw noSuchInstanceException;

	    // There are too many arcs left in the OID (there should remain
	    // a single trailing .0)
	    if (depth+2 < length)
		throw noSuchInstanceException;

	    // The last trailing arc is not .0
	    if (oid[depth+1] != 0L) 
		throw noSuchInstanceException;

	    // It's one of our variable, register this node.
	    handlers.add(this,depth,varbind);
	}
    }

    // -------------------------------------------------------------------
    // See comments in SnmpMibNode.
    // -------------------------------------------------------------------
    long[] findNextHandlingNode(SnmpVarBind varbind, 
				long[] oid, int pos, int depth, 
				SnmpRequestTree handlers, AcmChecker checker) 
	throws SnmpStatusException {
	
	int length = oid.length;
	SnmpMibNode node = null;
	
	if (handlers == null)
	    // This should be considered as a genErr, but we do not want to
	    // abort the whole request, so we're going to throw
	    // a noSuchObject...
	    //
            throw noSuchObjectException;

	final Object data = handlers.getUserData();
	final int pduVersion = handlers.getRequestPduVersion();


	// The generic case where the end of the OID has been reached is
	// handled in the superclass
        // XXX Revisit: this works but it is somewhat convoluted. Just setting
        //              arc to -1 would work too.
	if (pos >= length) 
	    return super.findNextHandlingNode(varbind,oid,pos,depth,
					      handlers, checker);

	// Ok, we've got the arc.
	long arc = oid[pos];

	long[] result = null;

	// We have a recursive logic. Should we have a loop instead?
	try {

	    if (isTable(arc)) {
		// If the arc identifies a table, then we need to forward
		// the search to the table.

		// Gets the table identified by `arc'
		SnmpMibTable table = getTable(arc);

		// Forward to the table
		checker.add(depth, arc);
		try {
		    result = table.findNextHandlingNode(varbind,oid,pos+1,
							depth+1,handlers,
							checker);
		}catch(SnmpStatusException ex) {
		    throw noSuchObjectException;
		} finally {
		    checker.remove(depth);
		}
		// Build up the leaf OID
		result[depth] = arc;
		return result;
	    } else if (isReadable(arc)) {
		// If the arc identifies a readable variable, then two cases:

		if (pos == (length - 1)) {
		    // The end of the OID is reached, so we return the leaf
		    // corresponding to the variable identified by `arc'

		    // Build up the OID
		    // result = new SnmpOid(0);
		    // result.insert((int)arc);
		    result = new long[depth+2];
		    result[depth+1] = 0L;
		    result[depth] = arc;

		    checker.add(depth, result, depth, 2);
		    try {
			checker.checkCurrentOid();
		    } catch(SnmpStatusException e) {
			throw noSuchObjectException;
		    } finally {
			checker.remove(depth,2);
		    }
		    
		    // Registers this node
		    handlers.add(this,depth,varbind);
		    return result;
		} 

		// The end of the OID is not yet reached, so we must return
		// the next leaf following the variable identified by `arc'.
		// We cannot return the variable because whatever follows in
		// the OID will be greater or equals to 0, and 0 identifies
		// the variable itself - so we have indeed to return the 
		// next object. 
		// So we do nothing, because this case is handled at the 
		// end of the if ... else if ... else ... block.

	    } else if (isNestedArc(arc)) {
		// Now if the arc leads to a subgroup, we delegate the 
		// search to the child, just as done in SnmpMibNode. 
		// 
  
		// get the child ( = nested arc node). 
		// 
		final SnmpMibNode child = getChild(arc); 
		
		if (child != null) { 
		    checker.add(depth, arc); 
		    try { 
			result = child.findNextHandlingNode(varbind,oid,pos+1, 
							    depth+1,handlers,  
							    checker); 
			result[depth] = arc; 
			return result;
		    } finally {
			checker.remove(depth);
		    }
		}
	    }
	    
	    // The oid is not valid, we will throw an exception in order
	    // to try with the next valid identifier...
	    //
	    throw noSuchObjectException;

	} catch (SnmpStatusException e) {
	    // We didn't find anything at the given arc, so we're going
	    // to try with the next valid arc
	    //
	    long[] newOid = new long[1];
	    newOid[0] = getNextVarId(arc,data,pduVersion);
	    return findNextHandlingNode(varbind,newOid,0,depth,
					handlers,checker);
	}
    }

}