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package com.sun.jmx.snmp.daemon;



// java imports
//
import java.util.Vector;
import java.util.Enumeration;

// jmx imports
//
import com.sun.jmx.snmp.SnmpOid;

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

The class is used for building a tree representation of the different root oids of the supported MIBs. Each node is associated to a specific MIB.
/** * The class is used for building a tree representation of the different * root oids of the supported MIBs. Each node is associated to a specific MIB. */
final class SnmpMibTree { public SnmpMibTree() { defaultAgent= null; root= new TreeNode(-1, null, null); } public void setDefaultAgent(SnmpMibAgent def) { defaultAgent= def; root.agent= def; } public SnmpMibAgent getDefaultAgent() { return defaultAgent; } public void register(SnmpMibAgent agent) { root.registerNode(agent); } public void register(SnmpMibAgent agent, long[] oid) { root.registerNode(oid, 0, agent); } public SnmpMibAgent getAgentMib(SnmpOid oid) { TreeNode node= root.retrieveMatchingBranch(oid.longValue(), 0); if (node == null) return defaultAgent; else if(node.getAgentMib() == null) return defaultAgent; else return node.getAgentMib(); } public void unregister(SnmpMibAgent agent, SnmpOid[] oids) { for(int i = 0; i < oids.length; i++) { long[] oid = oids[i].longValue(); TreeNode node = root.retrieveMatchingBranch(oid, 0); if (node == null) continue; node.removeAgent(agent); } } public void unregister(SnmpMibAgent agent) { root.removeAgentFully(agent); } /* public void unregister(SnmpMibAgent agent) { long[] oid= agent.getRootOid(); TreeNode node= root.retrieveMatchingBranch(oid, 0); if (node == null) return; node.removeAgent(agent); } */ public void printTree() { root.printTree(">"); } private SnmpMibAgent defaultAgent; private TreeNode root; // A SnmpMibTree object is a tree of TreeNode // final class TreeNode { void registerNode(SnmpMibAgent agent) { long[] oid= agent.getRootOid(); registerNode(oid, 0, agent); } TreeNode retrieveMatchingBranch(long[] oid, int cursor) { TreeNode node= retrieveChild(oid, cursor); if (node == null) return this; if (children.isEmpty()) { // In this case, the node does not have any children. So no point to // continue the search ... return node; } if( cursor + 1 == oid.length) { // In this case, the oid does not have any more element. So the search // is over. return node; } TreeNode n = node.retrieveMatchingBranch(oid, cursor + 1); //If the returned node got a null agent, we have to replace it by //the current one (in case it is not null) // return n.agent == null ? this : n; } SnmpMibAgent getAgentMib() { return agent; } public void printTree(String ident) { StringBuilder buff= new StringBuilder(); if (agents == null) { return; } for(Enumeration<SnmpMibAgent> e= agents.elements(); e.hasMoreElements(); ) { SnmpMibAgent mib= e.nextElement(); if (mib == null) buff.append("empty "); else buff.append(mib.getMibName()).append(" "); } ident+= " "; if (children == null) { return; } for(Enumeration<TreeNode> e= children.elements(); e.hasMoreElements(); ) { TreeNode node= e.nextElement(); node.printTree(ident); } } // PRIVATE STUFF //--------------
Only the treeNode class can create an instance of treeNode. The creation occurs when registering a new oid.
/** * Only the treeNode class can create an instance of treeNode. * The creation occurs when registering a new oid. */
private TreeNode(long nodeValue, SnmpMibAgent agent, TreeNode sup) { this.nodeValue= nodeValue; this.parent= sup; agents.addElement(agent); } private void removeAgentFully(SnmpMibAgent agent) { Vector<TreeNode> v = new Vector<>(); for(Enumeration<TreeNode> e= children.elements(); e.hasMoreElements(); ) { TreeNode node= e.nextElement(); node.removeAgentFully(agent); if(node.agents.isEmpty()) v.add(node); } for(Enumeration<TreeNode> e= v.elements(); e.hasMoreElements(); ) { children.removeElement(e.nextElement()); } removeAgent(agent); } private void removeAgent(SnmpMibAgent mib) { if (!agents.contains(mib)) return; agents.removeElement(mib); if (!agents.isEmpty()) agent= agents.firstElement(); } private void setAgent(SnmpMibAgent agent) { this.agent = agent; } private void registerNode(long[] oid, int cursor, SnmpMibAgent agent) { if (cursor >= oid.length) //That's it ! // return; TreeNode child = retrieveChild(oid, cursor); if (child == null) { // Create a child and register it ! // long theValue= oid[cursor]; child= new TreeNode(theValue, agent, this); children.addElement(child); } else if (agents.contains(agent) == false) { agents.addElement(agent); } // We have to set the agent attribute // if(cursor == (oid.length - 1)) { child.setAgent(agent); } else child.registerNode(oid, cursor+1, agent); } private TreeNode retrieveChild(long[] oid, int current) { long theValue= oid[current]; for(Enumeration<TreeNode> e= children.elements(); e.hasMoreElements(); ) { TreeNode node= e.nextElement(); if (node.match(theValue)) return node; } return null; } private boolean match(long value) { return (nodeValue == value) ? true : false; } private Vector<TreeNode> children= new Vector<>(); private Vector<SnmpMibAgent> agents= new Vector<>(); private long nodeValue; private SnmpMibAgent agent; private TreeNode parent; }; // end of class TreeNode }