snmpmibgroup.java

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

/* 
 * @(#)file      SnmpMibGroup.java 
 * @(#)author    Sun Microsystems, Inc. 
 * @(#)version   1.25 
 * @(#)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;

// java imports
// 
import java.io.Serializable;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Vector;

// jmx imports
//
import com.sun.jmx.snmp.SnmpOid;
import com.sun.jmx.snmp.SnmpValue;
import com.sun.jmx.snmp.SnmpVarBind;
import com.sun.jmx.snmp.SnmpStatusException;

// SNMP Runtime imports
//
import com.sun.jmx.snmp.agent.SnmpMibOid;
import com.sun.jmx.snmp.agent.SnmpMibNode;

/**
 * Represents a node in an SNMP MIB which corresponds to a group.
 * This class allows subnodes to be registered below a group, providing
 * support for nested groups. The subnodes are registered at run time
 * when registering the nested groups in the global MIB OID tree.
 * <P>
 * This class is used by the class generated by <CODE>mibgen</CODE>.
 * You should not need to use this class directly.
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject 
 * to change without notice.</b></p>
 * @version     4.3     10/29/99
 * @author      Sun Microsystems, Inc
 */

public abstract class SnmpMibGroup extends SnmpMibOid 
    implements Serializable {

    // We will register the OID arcs leading to subgroups in this hashtable.
    // So for each arc in varList, if the arc is also in subgroups, it leads
    // to a subgroup, if it is not in subgroup, it leads either to a table
    // or to a variable.
    protected Hashtable subgroups = null;

    /**
     * Tells whether the given arc identifies a table in this group.
     *
     * @param arc An OID arc.
     *
     * @return <CODE>true</CODE> if `arc' leads to a table.
     */
    public abstract boolean      isTable(long arc);

    /**
     * Tells whether the given arc identifies a variable (scalar object) in 
     * this group.
     *
     * @param arc An OID arc.
     *
     * @return <CODE>true</CODE> if `arc' leads to a variable.
     */
    public abstract boolean      isVariable(long arc);

    /**
     * Tells whether the given arc identifies a readable scalar object in 
     * this group.
     *
     * @param arc An OID arc.
     *
     * @return <CODE>true</CODE> if `arc' leads to a readable variable.
     */
    public abstract boolean      isReadable(long arc);


    /**
     * Gets the table identified by the given `arc'.
     *
     * @param arc An OID arc.
     *
     * @return The <CODE>SnmpMibTable</CODE> identified by `arc', or 
     *    <CODE>null</CODE> if `arc' does not identify any table.
     */
    public abstract SnmpMibTable getTable(long arc);

    /**
     * Checks whether the given OID arc identifies a variable (scalar 
     * object).
     *
     * @exception If the given `arc' does not identify any variable in this
     *    group, throws an SnmpStatusException.
     */
    public void validateVarId(long arc, Object userData) 
	throws SnmpStatusException {
	if (isVariable(arc) == false) 
	    throw noSuchObjectException;
    }
	
	
    // -------------------------------------------------------------------
    // We use a hashtable (subgroup) in order to determine whether an
    // OID arc leads to a subgroup. This implementation can be changed if 
    // needed...
    // For instance, the subclass could provide a generated isNestedArc() 
    // method in which the subgroup OID arcs would be hardcoded.
    // However, the generic approach was prefered because at this time
    // groups and subgroups are dynamically registered in the MIB.
    //
    /**
     * Tell whether the given OID arc identifies a sub-tree
     * leading to a nested SNMP sub-group. This method is used internally.
     * You shouldn't need to call it directly.
     *
     * @param arc An OID arc.
     *
     * @return <CODE>true</CODE> if the given OID arc identifies a subtree
     * leading to a nested SNMP sub-group.
     *
     */
    public boolean isNestedArc(long arc) {
	if (subgroups == null) return false;
	Object obj = subgroups.get(new Long(arc));
        // if the arc is registered in the hashtable, 
	// it leads to a subgroup.
	return (obj != null);
    }

    /**
     * Generic handling of the <CODE>get</CODE> operation.
     * <p>The actual implementation of this method will be generated
     * by mibgen. Usually, this implementation only delegates the
     * job to some other provided runtime class, which knows how to
     * access the MBean. The current toolkit thus provides two 
     * implementations:
     * <ul><li>The standard implementation will directly access the
     *         MBean through a java reference,</li>
     *     <li>The generic implementation will access the MBean through
     *         the MBean server.</li>
     * </ul>
     * <p>Both implementations rely upon specific - and distinct, set of
     * mibgen generated methods.
     * <p> You can override this method if you need to implement some
     * specific policies for minimizing the accesses made to some remote
     * underlying resources.
     * <p>
     *
     * @param req   The sub-request that must be handled by this node.
     *
     * @param depth The depth reached in the OID tree.
     *
     * @exception SnmpStatusException An error occurred while accessing 
     *  the MIB node.
     */
    abstract public void get(SnmpMibSubRequest req, int depth) 
	throws SnmpStatusException;

    /**
     * Generic handling of the <CODE>set</CODE> operation.
     * <p>The actual implementation of this method will be generated
     * by mibgen. Usually, this implementation only delegates the
     * job to some other provided runtime class, which knows how to
     * access the MBean. The current toolkit thus provides two 
     * implementations:
     * <ul><li>The standard implementation will directly access the
     *         MBean through a java reference,</li>
     *     <li>The generic implementation will access the MBean through
     *         the MBean server.</li>
     * </ul>
     * <p>Both implementations rely upon specific - and distinct, set of
     * mibgen generated methods.
     * <p> You can override this method if you need to implement some
     * specific policies for minimizing the accesses made to some remote
     * underlying resources.
     * <p>
     *
     * @param req   The sub-request that must be handled by this node.
     *
     * @param depth The depth reached in the OID tree.
     *
     * @exception SnmpStatusException An error occurred while accessing 
     *  the MIB node.
     */
    abstract public void set(SnmpMibSubRequest req, int depth) 
	throws SnmpStatusException;

    /**
     * Generic handling of the <CODE>check</CODE> operation.
     *
     * <p>The actual implementation of this method will be generated
     * by mibgen. Usually, this implementation only delegates the
     * job to some other provided runtime class, which knows how to
     * access the MBean. The current toolkit thus provides two 
     * implementations:
     * <ul><li>The standard implementation will directly access the
     *         MBean through a java reference,</li>
     *     <li>The generic implementation will access the MBean through
     *         the MBean server.</li>
     * </ul>
     * <p>Both implementations rely upon specific - and distinct, set of
     * mibgen generated methods.
     * <p> You can override this method if you need to implement some
     * specific policies for minimizing the accesses made to some remote
     * underlying resources, or if you need to implement some consistency
     * checks between the different values provided in the varbind list.
     * <p>
     *
     * @param req   The sub-request that must be handled by this node.
     *
     * @param depth The depth reached in the OID tree.
     *
     * @exception SnmpStatusException An error occurred while accessing 
     *  the MIB node.
     */
    abstract public void check(SnmpMibSubRequest req, int depth) 
	throws SnmpStatusException;

    // --------------------------------------------------------------------
    // If we reach this node, we are below the root OID, so we just
    // return.
    // --------------------------------------------------------------------
    public void getRootOid(Vector result) {
	return;
    }

    // -------------------------------------------------------------------
    // PACKAGE METHODS
    // -------------------------------------------------------------------
    
    // -------------------------------------------------------------------
    // This method can also be overriden in a subclass to provide a 
    // different implementation of the isNestedArc() method.
    // => if isNestedArc() is hardcoded, then registerSubArc() becomes
    //    useless and can become empty.
    /**
     * Register an OID arc that identifies a sub-tree
     * leading to a nested SNMP sub-group. This method is used internally.
     * You shouldn't ever call it directly.
     *
     * @param arc An OID arc.
     *
     */
    void registerNestedArc(long arc) {
	Long obj = new Long(arc);
	if (subgroups == null) subgroups = new Hashtable();