blockpdu.java

snmp zip 包开发snmp协议

// NAME
//      $RCSfile: BlockPdu.java,v $
// DESCRIPTION
//      [given below in javadoc format]
// DELTA
//      $Revision: 3.13 $
// CREATED
//      $Date: 2006/01/17 17:43:53 $
// COPYRIGHT
//      Westhawk Ltd
// TO DO
//

/*
 * Copyright (C) 2000 - 2006 by Westhawk Ltd
 * <a href="www.westhawk.co.uk">www.westhawk.co.uk</a>
 *
 * Permission to use, copy, modify, and distribute this software
 * for any purpose and without fee is hereby granted, provided
 * that the above copyright notices appear in all copies and that
 * both the copyright notice and this permission notice appear in
 * supporting documentation.
 * This software is provided "as is" without express or implied
 * warranty.
 * author <a href="mailto:[e-mail]">Tim Panton</a>
 */
 
package uk.co.westhawk.snmp.pdu;
import uk.co.westhawk.snmp.stack.*;
import java.util.*;

/**
 * The BlockPdu class is a wrapper class that will block until it
 * receives the answer. 
 *
 * @see uk.co.westhawk.snmp.stack.Pdu
 *
 * @author <a href="mailto:[e-mail]">Birgit Arkesteijn</a>
 * @version $Revision: 3.13 $ $Date: 2006/01/17 17:43:53 $
 */
public class BlockPdu extends Object 
{
    private static final String     version_id =
        "@(#)$Id: BlockPdu.java,v 3.13 2006/01/17 17:43:53 birgit Exp $ Copyright Westhawk Ltd";

    /**
     * The GET PDU type.
     */
    public final static int GET = 0;
    /**
     * The SET PDU type.
     */
    public final static int SET = 1;
    /**
     * The GETNEXT PDU type.
     */
    public final static int GETNEXT = 2;
    /**
     * The GETBULK PDU type. Note, the getBulkRequest was introduced in
     * SNMPv2c. For that reason it should not be sent with SNMPv1.
     */
    public final static int GETBULK = 3;

    protected Vector reqVarbinds;
    private SnmpContextBasisFace context;
    private Pdu pdu;
    private int type = GET;
    private int non_rep = 0;
    private int max_rep = 0;
    private int retry_intervals[] = null;

/**
 * Constructor.
 *
 * @param con The context of the request
 */
public BlockPdu(SnmpContextBasisFace con)
{
    context = con;
    reqVarbinds = new Vector(1,1);
}

/** 
 * Adds an OID to the PDU. 
 *
 * @param oid The oid 
 * @see uk.co.westhawk.snmp.stack.Pdu#addOid(String)
 */
public void addOid(String oid)
{
    varbind vb = new varbind(oid);
    addOid(vb);
}

/** 
 * Adds an OID to the PDU and the value that has to be set. 
 * This is only useful for the SET type.
 *
 * @param oid The oid 
 * @see uk.co.westhawk.snmp.stack.SetPdu#addOid(String, AsnObject)
 * @see #SET
 */
public void addOid(String oid, AsnObject val)
{
    varbind vb = new varbind(oid, val);
    addOid(vb);
}

/** 
 * Adds an OID (object identifier) to the PDU and the value that has
 * to be set. 
 * This is only useful for the SET type.
 *
 * @param oid The oid 
 * @param val The value 
 * @see Pdu#addOid(AsnObjectId, AsnObject)
 * @see varbind
 * @since 4_12
 */
public void addOid(AsnObjectId oid, AsnObject val) 
{
    varbind vb = new varbind(oid, val);
    addOid(vb);
}

/** 
 * Adds an OID (object identifier) to the PDU. The OID indicates which
 * MIB variable we request or which MIB variable should be set.
 *
 * @param oid The oid 
 * @see Pdu#addOid(AsnObjectId)
 * @see varbind
 * @since 4_12
 */
public void addOid(AsnObjectId oid) 
{
    varbind vb = new varbind(oid);
    addOid(vb);
}

/** 
 * Adds an OID (object identifier) to the PDU. 
 *
 * @param var The varbind 
 * @see #addOid(String)
 */
public void addOid(varbind var)
{
    reqVarbinds.addElement(var);
}

/** 
 * Sets the getBulkRequest parameters. 
 * This is only useful for the GETBULK type.
 * If these parameters are not set, they both default to zero.
 *
 * @param nr The non repeaters.
 * @param mr The max repetitions. 
 * @see uk.co.westhawk.snmp.stack.GetBulkPdu#setMaxRepetitions(int)
 * @see uk.co.westhawk.snmp.stack.GetBulkPdu#setNonRepeaters(int)
 * @see #GETBULK
 */
public void setBulkParameters(int nr, int mr)
{
    non_rep = nr;
    max_rep = mr;
}

/** 
 * Adds a list of OIDs to the PDU.
 *
 * @param oids The OIDs to be added
 */
public void addOid(String[] oids)
{
    for (int i=0; i<oids.length; i++)
    {
        varbind vb = new varbind(oids[i]);
        reqVarbinds.addElement(vb);
    }
}

/**
 * Sets the type of PDU. The type indicates the kind of request, i.e.
 * the getRequest (the default), the setRequest, the getNextRequest, or
 * the getBulkRequest.
 *
 * @param newType The type of request
 * @see #GET
 * @see #SET
 * @see #GETNEXT
 * @see #GETBULK
 */
public void setPduType(int newType)
{
    type = newType;
}

/**
 * Sets the retry intervals of the PDU. This method overwrites the
 * default values in the PDU class.
 *
 * @param retryIntervals The interval in msec of each retry
 * @see uk.co.westhawk.snmp.stack.Pdu#setRetryIntervals(int[])
 */
public void setRetryIntervals(int retryIntervals[])
{
    retry_intervals = retryIntervals;
}

/**
 * Sends the request and waits (blocks) for the response. Returns the
 * value of the first variable binding in the response. If no response was 
 * received, this will be null.
 * 
 * @return The value of the first variable binding in the response
 * @see #sendAndWait()
 */
public AsnObject getResponseVariable() 
throws PduException, java.io.IOException
{
    AsnObject value = null;
    varbind[] vars = sendAndWait();
    if (vars != null && vars.length > 0)
    {
        value = vars[0].getValue();
    }
    return value;
}

/**
 * Sends the request and waits (blocks) for the response. Returns the
 * values of the variable bindings in the response. If no response was 
 * received, this will be null.
 * 
 * @return The values of the variable bindings in the response
 * @see #sendAndWait()
 */
public AsnObject[] getResponseVariables() 
throws PduException, java.io.IOException
{
    AsnObject[] values = null;
    varbind[] vars = sendAndWait();
    if (vars != null)
    {
        values = new AsnObject[vars.length];
        for (int i=0; i<vars.length; i++)
        {
            values[i] = vars[i].getValue();
        }
    }
    return values;
}

/**
 * Sends the request and waits (blocks) for the response. Returns the
 * first variable binding in the response. If no response was received, this
 * will be null.
 * 
 * @return The first variable binding in the response
 * @see #sendAndWait()
 */
public varbind getResponseVariableBinding() 
throws PduException, java.io.IOException
{
    varbind var = null;
    varbind[] vars = sendAndWait();
    if (vars != null && vars.length > 0)
    {
        var = vars[0];
    }
    return var;
}

/**
 * Sends the request and waits (blocks) for the response. Returns the
 * variable bindings in the response. If no response was received, this
 * will be null.
 * 
 * @return The variable bindings in the response
 * @see #sendAndWait()
 */
public varbind[] getResponseVariableBindings() 
throws PduException, java.io.IOException
{
    varbind[] vars = sendAndWait();
    return vars;
}

/**
 * Sends the request and waits (blocks) for the response. This is the core 
 * of the blocking getResponseVariableX() methods.
 * 
 * @return The response, can be null if there was a timeout
 * @see uk.co.westhawk.snmp.stack.Pdu#send()
 * @see uk.co.westhawk.snmp.stack.Pdu#waitForSelf()
 * @see uk.co.westhawk.snmp.stack.Pdu#getResponseVarbinds()
 */
protected synchronized varbind[] sendAndWait() 
throws PduException, java.io.IOException
{
    int sz = reqVarbinds.size();
    switch (type)
    {
        case SET:
        {
            pdu = new SetPdu_vec(context, sz);
            break;
        }
        case GETNEXT:
        {
            pdu = new GetNextPdu_vec(context, sz);
            break;
        }
        case GETBULK:
        {
            pdu = new GetBulkPdu(context);
            ((GetBulkPdu)pdu).setNonRepeaters(non_rep);
            ((GetBulkPdu)pdu).setMaxRepetitions(max_rep);
            break;
        }
        default:
        {
            pdu = new GetPdu_vec(context, sz);
        }
    }
    for (int i=0; i<sz; i++)
    {
        varbind var = (varbind) reqVarbinds.elementAt(i);
        pdu.addOid(var);
    }
    if (retry_intervals != null)
    {
        pdu.setRetryIntervals(retry_intervals);
    }
    pdu.send();
    pdu.waitForSelf();
    varbind [] vars = pdu.getResponseVarbinds();
    return vars;
}

/**
 * Returns the error index of the PDU.
 * This will only have been set after the response is received.
 * Thanks to Maga Hegde ([e-mail]) to requesting this method.
 *
 * @see uk.co.westhawk.snmp.stack.Pdu#getErrorIndex()
 * @return The error index
 */
public int getErrorIndex()
{
    return pdu.getErrorIndex();
}

/**
 * Returns the error status of the PDU.
 * This will only have been set after the response is received.
 *
 * @see uk.co.westhawk.snmp.stack.Pdu#getErrorStatus()
 * @return The error status
 */
public int getErrorStatus()
{
    return pdu.getErrorStatus();
}


/**
 * Returns the error status string of the PDU.
 * This will only have been set after the response is received.
 *
 * @see uk.co.westhawk.snmp.stack.Pdu#getErrorStatusString()
 * @return The error status string
 */
public String getErrorStatusString()
{
    return pdu.getErrorStatusString();
}

}