snmpcontextv3pool.java

无线网络管理

    byte [] res = null;
    if (context != null)
    {
        res = context.encodeDiscoveryPacket(msg_type, rId, errstat, errind, ve, obj);
    }
    return res;
}


public byte [] encodePacket(byte msg_type, int rId, int errstat,
      int errind, Enumeration ve, Object obj)
      throws java.io.IOException, EncodingException
{
    byte [] res = null;
    if (context != null)
    {
        res = context.encodePacket(msg_type, rId, errstat, errind, ve,
        obj);
    }
    return res;
}

public void sendPacket(byte[] packet)
{
    if (context != null)
    {
        context.sendPacket(packet);
    }
}

/**
 * Releases the resources held by this context. This method will
 * decrement the reference counter. When the reference counter reaches
 * zero the actual context is removed from the pool and destroyed.
 */
public void destroy()
{
    try
    {
        if (hasChanged == true)
        {
            context = getMatchingContext();
        }
    }
    catch (java.io.IOException exc) 
    {
        if (AsnObject.debug > 0)
        {
            System.out.println(getClass().getName() + ".destroy(): " + exc.getMessage());
        }
    }

    if (context != null)
    {
        String hashKey = getHashKey();
        synchronized(contextPool)
        {
            int count = 0;
            SnmpContextPoolItem item = (SnmpContextPoolItem) contextPool.get(hashKey);
            if (item != null)
            {
                count = item.getCounter();
                count--;
                item.setCounter(count);
            }

            if (count <= 0)
            {
                contextPool.remove(hashKey);
                context.destroy();
                context = null;
            }
        }
    }
}

/**
 * Destroys all the contexts in the pool and empties the pool. 
 *
 * @see #destroy()
 * @since 4_14
 */
public void destroyPool()
{
    Hashtable copyOfPool = null;

    synchronized(contextPool)
    {
        synchronized(contextPool)
        {
            copyOfPool = (Hashtable) contextPool.clone();
        }
        contextPool.clear();
    }
    context = null;
    hasChanged = true;

    Enumeration keys = copyOfPool.keys();
    while (keys.hasMoreElements())
    {
        String key = (String) keys.nextElement();
        SnmpContextPoolItem item = (SnmpContextPoolItem) copyOfPool.get(key);
        if (item != null)
        {
            SnmpContextBasisFace cntxt = (SnmpContextBasisFace) item.getContext();
            cntxt.destroy();
        }
    }
    copyOfPool.clear();
}


public boolean isDestroyed()
{
    boolean isDestroyed = true;
    if (context != null)
    {
        isDestroyed = context.isDestroyed();
    }
    return isDestroyed;
}

/**
 * Returns a context from the pool.
 * This methods checks for an existing context that matches all our
 * properties. If such a context does not exist, a new one is created and
 * added to the pool.
 *
 * @return A context from the pool
 * @see #getHashKey
 */
protected SnmpContextv3 getMatchingContext()
throws java.io.IOException, IllegalArgumentException
{
    SnmpContextPoolItem item = null;
    SnmpContextv3 newContext = null;
    String hashKey = getHashKey();

    synchronized(contextPool)
    {
        int count=0;
        if (contextPool.containsKey(hashKey))
        {
            item = (SnmpContextPoolItem) contextPool.get(hashKey);
            newContext = (SnmpContextv3) item.getContext();
            count = item.getCounter();
        }
        else
        {
            newContext = new SnmpContextv3(hostname, hostPort, bindAddr, socketType);
            newContext.setContextEngineId(contextEngineId);
            newContext.setContextName(contextName);
            newContext.setUserName(userName);
            newContext.setUseAuthentication(useAuthentication);
            newContext.setUserAuthenticationPassword(userAuthenticationPassword);
            newContext.setAuthenticationProtocol(authenticationProtocol);
            newContext.setUsePrivacy(usePrivacy);
            newContext.setUserPrivacyPassword(userPrivacyPassword);
            newContext.setUsmAgent(usmAgent);

            item = new SnmpContextPoolItem(newContext);
            contextPool.put(hashKey, item);
        }
        hasChanged = false;
        count++;
        item.setCounter(count);
    }
    return newContext;
}

/**
 * Dumps the pool of contexts. This is for debug purposes.
 * @param title The title of the dump
 */
public void dumpContexts(String title)
{
    try
    {
        if (hasChanged == true)
        {
            context = getMatchingContext();
        }
    }
    catch (java.io.IOException exc) 
    {
        if (AsnObject.debug > 0)
        {
            System.out.println(getClass().getName() + ".dumpContexts(): " + exc.getMessage());
        }
    }

    System.out.println(title + " " + contextPool.size() + " context(s)");
    Enumeration keys = contextPool.keys();
    int i=0;
    while (keys.hasMoreElements())
    {
        String key = (String) keys.nextElement();
        SnmpContextPoolItem item = (SnmpContextPoolItem) contextPool.get(key);
        if (item != null)
        {
            int count = item.getCounter();
            SnmpContextv3 cntxt = (SnmpContextv3) item.getContext();

            if (cntxt == context)
            {
                System.out.println("\tcurrent context: ");
            }
            System.out.println("\tcontext " + i + ": " + key + ", count: " + count
                + ", " + cntxt.toString() + "\n"
                + ", " + cntxt.getDebugString());
            i++;
        }
    }
    System.out.println("\thasChanged: " + hasChanged);
}


/**
 * Returns the hash key. This key is built out of all properties. It
 * serves as key for the hashtable of (v3) contexts.
 *
 * @return The hash key
 */
public String getHashKey()
{
    StringBuffer buffer = new StringBuffer();
    buffer.append(hostname);
    buffer.append("_").append(hostPort);
    buffer.append("_").append(bindAddr);
    buffer.append("_").append(socketType);
    buffer.append("_").append(useAuthentication);
    buffer.append("_").append(authenticationProtocol);
    buffer.append("_").append(userAuthenticationPassword);
    buffer.append("_").append(userName);
    buffer.append("_").append(usePrivacy);
    buffer.append("_").append(userPrivacyPassword);
    buffer.append("_").append(SnmpUtilities.toHexString(contextEngineId));
    buffer.append("_").append(contextName);
    buffer.append("_v").append(getVersion());

    return buffer.toString();
}

public void addTrapListener(TrapListener l) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addTrapListener(l);
}

public void removeTrapListener(TrapListener l) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeTrapListener(l);
}

public void addTrapListener(TrapListener l, int port) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addTrapListener(l, port);
}

public void removeTrapListener(TrapListener l, int port) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeTrapListener(l, port);
}


public void addTrapListener(TrapListener l, ListeningContextPool lcontext) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addTrapListener(l, lcontext);
}

public void removeTrapListener(TrapListener l, ListeningContextPool lcontext) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeTrapListener(l, lcontext);
}


public void addRequestPduListener(RequestPduListener l) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addRequestPduListener(l);
}

public void removeRequestPduListener(RequestPduListener l) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeRequestPduListener(l);
}

public void addRequestPduListener(RequestPduListener l, int port) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addRequestPduListener(l, port);
}

public void removeRequestPduListener(RequestPduListener l, int port) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeRequestPduListener(l, port);
}


public void addRequestPduListener(RequestPduListener l, ListeningContextPool lcontext) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.addRequestPduListener(l, lcontext);
}

public void removeRequestPduListener(RequestPduListener l, ListeningContextPool lcontext) throws java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }
    context.removeRequestPduListener(l, lcontext);
}


public Pdu processIncomingPdu(byte [] message)
throws DecodingException, java.io.IOException
{
    if (hasChanged == true || context == null)
    {
        context = getMatchingContext();
    }

    Pdu pdu = null;
    pdu = context.processIncomingPdu(message);
    return pdu;
}

/**
 * Returns a string representation of the object.
 * @return The string
 */
public String toString()
{
    String res = "";
    try
    {
        if (hasChanged == true || context == null)
        {
            context = getMatchingContext();
        }
        res = context.toString();
    }
    catch (java.io.IOException exc) 
    {
        if (AsnObject.debug > 0)
        {
            System.out.println(getClass().getName() + ".toString(): " + exc.getMessage());
        }
    }

    return res;
}

/**
 * This method is not supported. It will throw a CloneNotSupportedException.
 *
 * @since 4_14
 */
public Object clone() throws CloneNotSupportedException
{
    throw new CloneNotSupportedException();
}

}