snmprequesttree.java

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

/* 
 * @(#)file      SnmpRequestTree.java 
 * @(#)author    Sun Microsystems, Inc. 
 * @(#)version   1.27 
 * @(#)date      08/09/12 
 * 
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */ 
package com.sun.jmx.snmp.agent;

import java.util.Vector;
import java.util.ArrayList;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Arrays;
import com.sun.jmx.snmp.SnmpVarBind;
import com.sun.jmx.snmp.SnmpStatusException;
import com.sun.jmx.snmp.SnmpDefinitions;
import com.sun.jmx.snmp.SnmpOid;
import com.sun.jmx.snmp.SnmpPdu;
import com.sun.jmx.snmp.SnmpEngine;
import com.sun.jmx.trace.Trace;

//  XXX: things to do: use SnmpOid rather than `instance' for future
//       evolutions.
//  XXX: Maybe use hashlists rather than vectors for entries?
//       => in that case, the key should be SnmpOid.toString()
//
/**
 * This class is used to register varbinds from a SNMP varbind list with
 * the SnmpMibNode responsible for handling the requests concerning that
 * varbind. 
 * This class holds a hashtable of Handler nodes, whith the involved 
 * SnmpMibNode as a key. 
 * When the involved SnmpMibNode is a group, the sublist of varbind is
 * directly stored in the Handler node. 
 * When the involved SnmpMibNode is a table, the sublist is stored in a 
 * sorted array indexed by the OID of the entry involved. 
 */
final class SnmpRequestTree {

    // Constructor:
    // @param  req The SnmpMibRequest that will be segmented in this
    //         tree. It holds the original varbind vector passed
    //         by the SnmpSubRequestHandler to this MIB. This
    //         varbind vector is used to retrieve the "real"
    //         position of a varbind in the vector. There is no other easy 
    //         way to do this - since as a result of the segmentation the
    //         original positions will be lost.
    // @param  creationflag indicates whether the operation involved
    //         allows for entry creation (ie: it is a SET request).
    // @param  pdutype indicates the type of the request PDU as defined
    //         in SnmpDefinitions
    //
    SnmpRequestTree(SnmpMibRequest req, boolean creationflag, int pdutype) {
	this.request = req;
	this.version  = req.getVersion();
	this.creationflag = creationflag;
	this.hashtable = new Hashtable();
	setPduType(pdutype);
    }

    public static int mapSetException(int errorStatus, int version) 
	throws SnmpStatusException {

	final int errorCode = errorStatus;

	if (version == SnmpDefinitions.snmpVersionOne) 
	    return errorCode;
	
	int mappedErrorCode = errorCode;
	
	// Now take care of V2 errorCodes that can be stored
	// in the varbind itself:
	if (errorCode == SnmpStatusException.noSuchObject)
	    // noSuchObject => notWritable
	    mappedErrorCode = SnmpStatusException.snmpRspNotWritable;
	
	else if (errorCode == SnmpStatusException.noSuchInstance)
	    // noSuchInstance => notWritable
	    mappedErrorCode = SnmpStatusException.snmpRspNotWritable;

	return mappedErrorCode;
    }

    public static int mapGetException(int errorStatus, int version) 
	throws SnmpStatusException {

	final int errorCode = errorStatus;
	if (version == SnmpDefinitions.snmpVersionOne)
	    return errorCode;
	
	int mappedErrorCode = errorCode;
	
	// Now take care of V2 errorCodes that can be stored
	// in the varbind itself:
	if (errorCode == 
	    SnmpStatusException.noSuchObject)
	    // noSuchObject => noSuchObject
	    mappedErrorCode = errorCode;
	
	else if (errorCode == 
		 SnmpStatusException.noSuchInstance)
	    // noSuchInstance => noSuchInstance
	    mappedErrorCode = errorCode;
	
	// Now we're going to try to transform every other
	// global code in either noSuchInstance or noSuchObject,
	// so that the get can return a partial result.
	//
	// Only noSuchInstance or noSuchObject can be stored
	// in the varbind itself.
	//
	
	// According to RFC 1905: noAccess is emitted when the
	// the access is denied because it is not in the MIB view...
	// 
	else if (errorCode ==
		 SnmpStatusException.noAccess)
	    // noAccess => noSuchInstance
	    mappedErrorCode = SnmpStatusException.noSuchInstance;
	
	// According to RFC 1905: (my interpretation because it is not
	// really clear) The specified variable name exists - but the
	// variable does not exists and cannot be created under the
	// present circumstances (probably because the request specifies
	// another variable/value which is incompatible, or because the
	// value of some other variable in the MIB prevents the creation)
	//
	// Note that this error should never be raised in a GET context
	// but who knows?
	//
	else if (errorCode == SnmpStatusException.snmpRspInconsistentName)
	    // inconsistentName => noSuchInstance
	    mappedErrorCode = SnmpStatusException.noSuchInstance;
	
	// All the errors comprised between snmpRspWrongType and
	// snmpRspInconsistentValue concern values: so we're going
	// to assume the OID was correct, and reply with noSuchInstance.
	//
	// Note that this error should never be raised in a GET context
	// but who knows?
	//
	else if ((errorCode >= SnmpStatusException.snmpRspWrongType) &&
		 (errorCode <= SnmpStatusException.snmpRspInconsistentValue))
	    mappedErrorCode = SnmpStatusException.noSuchInstance;
	
	// We're going to assume the OID was correct, and reply 
	// with noSuchInstance.
	//
	else if (errorCode == SnmpStatusException.readOnly)
	    mappedErrorCode = SnmpStatusException.noSuchInstance;
	
	// For all other errors but genErr, we're going to reply with
	// noSuchObject
	//
	else if (errorCode != SnmpStatusException.snmpRspAuthorizationError &&
		 errorCode != SnmpStatusException.snmpRspGenErr)
	    mappedErrorCode = SnmpStatusException.noSuchObject;
	
	// Only genErr will abort the GET and be returned as global
	// error.
	//
	return mappedErrorCode;
	
    }

    //-------------------------------------------------------------------
    // This class is a package implementation of the enumeration of
    // SnmSubRequest associated with an Handler node.
    //-------------------------------------------------------------------

    static final class Enum implements Enumeration {
	Enum(SnmpRequestTree hlist,Handler h) {
	    handler = h;
	    this.hlist = hlist;
	    size = h.getSubReqCount();
	}
	private final Handler handler;
	private final SnmpRequestTree hlist;
	private int   entry = 0;
	private int   iter  = 0;
	private int   size  = 0;
	
	public boolean hasMoreElements() {
	    return iter < size;
	}

	public Object nextElement() throws NoSuchElementException  {
	    if (iter == 0) {
		if (handler.sublist != null) {
		    iter++;
		    return hlist.getSubRequest(handler);
		}
	    }
	    iter ++;
	    if (iter > size) throw new NoSuchElementException();
	    Object result = hlist.getSubRequest(handler,entry); 
	    entry++;
	    return result;
	}
    }

    //-------------------------------------------------------------------
    // This class is a package implementation of the SnmpMibSubRequest
    // interface. It can only be instantiated by SnmpRequestTree.
    //-------------------------------------------------------------------

    static final class SnmpMibSubRequestImpl implements SnmpMibSubRequest {
	SnmpMibSubRequestImpl(SnmpMibRequest global, Vector sublist, 
			   SnmpOid entryoid, boolean isnew, 
			   boolean getnextflag, SnmpVarBind rs) {
	    this.global = global;
	    varbinds           = sublist;
	    this.version       = global.getVersion();
	    this.entryoid      = entryoid;
	    this.isnew         = isnew;
	    this.getnextflag   = getnextflag;
	    this.statusvb      = rs;
	}

	final private Vector         varbinds;
	final private SnmpMibRequest global;
	final private int            version;
	final private boolean        isnew;
	final private SnmpOid        entryoid;
	final private boolean        getnextflag;
	final private SnmpVarBind    statusvb;

	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public Enumeration getElements() {
	    return varbinds.elements();
	}
	
	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public Vector getSubList() {
	    return varbinds;
	}
	
	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public final int getSize()  {
	    if (varbinds == null) return 0;
	    return varbinds.size();
	}

	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public void addVarBind(SnmpVarBind varbind) {
	    // XXX not sure we must also add the varbind in the global 
	    //     request? or whether we should raise an exception:
	    //     in principle, this method should not be called!
	    varbinds.addElement(varbind);
	    global.addVarBind(varbind);
	}

	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibSubRequest interface.
	// See SnmpMibSubRequest for the java doc.
	// -------------------------------------------------------------
	public boolean isNewEntry() {
	    return isnew;
	}
	
	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibSubRequest interface.
	// See SnmpMibSubRequest for the java doc.
	// -------------------------------------------------------------
	public SnmpOid getEntryOid() {
	    return entryoid;
	}
	
	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public int getVarIndex(SnmpVarBind varbind) {
	    if (varbind == null) return 0;
	    return global.getVarIndex(varbind);
	}

	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibRequest interface.
	// See SnmpMibRequest for the java doc.
	// -------------------------------------------------------------
	public Object getUserData() { return global.getUserData(); }


	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibSubRequest interface.
	// See SnmpMibSubRequest for the java doc.
	// -------------------------------------------------------------
	
	public void registerGetException(SnmpVarBind var,
					 SnmpStatusException exception)
	    throws SnmpStatusException {
	    // The index in the exception must correspond to 
	    // the SNMP index ...
	    //
	    if (version == SnmpDefinitions.snmpVersionOne)
		throw new SnmpStatusException(exception, getVarIndex(var)+1);

	    if (var == null) 
		throw exception;

	    // If we're doing a getnext ==> endOfMibView
	    if (getnextflag) {
		var.value = SnmpVarBind.endOfMibView;
		return;
	    }

	    final int errorCode = mapGetException(exception.getStatus(),
						  version);

	    // Now take care of V2 errorCodes that can be stored
	    // in the varbind itself:
	    if (errorCode == 
		SnmpStatusException.noSuchObject)
		// noSuchObject => noSuchObject
		var.value= SnmpVarBind.noSuchObject;

	    else if (errorCode == 
		     SnmpStatusException.noSuchInstance)
		// noSuchInstance => noSuchInstance
		var.value= SnmpVarBind.noSuchInstance;

	    else 
		throw new SnmpStatusException(errorCode, getVarIndex(var)+1);

	}
	
	// -------------------------------------------------------------
	// Implements the method defined in SnmpMibSubRequest interface.
	// See SnmpMibSubRequest for the java doc.
	// -------------------------------------------------------------
	public void registerSetException(SnmpVarBind var,
					 SnmpStatusException exception)
	    throws SnmpStatusException {
	    // The index in the exception must correspond to