mmepunit.java

一个完整的XACML工程,学习XACML技术的好例子!

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package issrg.pba.rbac.policies;


/**
 * This class represents a MMEP unit -- it includes a forbiddenCardinality and a privilege set 
 * which comprises several mutually exclusive privileges with the forbiddenCardinality.  
 *
 * @author W.Xu
 * @version 0.1
 */
  public class MMEPUnit {

      private int forbiddenCardinality;
      private int matchCount = 0;  
      java.util.Vector mmep;  // this is a vector of class UserAction
      java.util.Vector mmepBackup;

    /**
     * This constructor creates the MMEPUnit object. 
     *
     * @params forbiddenCardinality is the forbidden cardinality of this MMEP unit.  
     * @params mmep is a vector of MMEP i.e. mutually exclusive privileges. 
     * 
     */
      public MMEPUnit(int forbiddenCardinality, java.util.Vector mmep) {
          this.forbiddenCardinality = forbiddenCardinality;
          this.mmep = mmep;  
      }

     /**
      * This method returns the current match count of MMEP, 
      * i.e. until now, how many MMEP have been matched by the user actions this MMEP Unit. 
      */
      public int getMatchCount(){
          return matchCount;
      }

     /**
      * This method starts a new matching between user actions and this MMEP unit.  
      */
      public void startMatch(){
          mmepBackup = (java.util.Vector) mmep.clone();
          matchCount = 0;
      }

    /**
     * This method compare mmep with the input user action and target, 
     * to determine if this action and target pair match any mmep privileges. Once matched, matchCount is increased by 1, 
     * and if matchCount reaches forbiddenCardinality, then this MMEP rule is broken by the user, true will be returned; 
     * otherwise, false will be returned. 
     * 
     * return true if this user action and target matches any one of the MMEP privilege and the forbeddenCardinality
     * is reached; otherwise return false.  
     */
      public boolean MMEPMatches(String action, String target) {
          if (mmepBackup == null) { 
              return false; 
          }

          for (int i=mmepBackup.size()-1; i>=0 ; --i )    {
              UserAction ua = (UserAction) mmepBackup.get(i); 
              if ( (ua.getAction()).compareTo(action) == 0 && ua.getTarget().compareTo(target) ==0 )  {  // they are equal 
                mmepBackup.remove(i); 
                matchCount++;
                if (matchCount >= forbiddenCardinality) {
                  // System.out.println("rule broken " );
                  return true; 
                }
                break; 
              }
          }

          return false; 
      }

     /**
      * This method is to output all the MMEP action information as a String. This is for testing purposes. 
      */
      public String toString(){
		// testing code here
		  int size = mmep.size();
		  StringBuffer result = new StringBuffer();
		  for (int i = 0; i< size ; i++ ) {
			    UserAction ua = (UserAction) mmep.get(i);
				result.append ( ua.toString() );
		  }
		  
		  return result.toString();
	  }  

  }