resourcemonitor.java

来自「First of all, the Applet-phone is a SIP 」· Java 代码 · 共 60 行

/*
 * ResourceMonitor.java
 *
 * Created on July 28, 2003, 9:45 AM
 */

package gov.nist.security.bcs.monitor;

import org.apache.log4j.Logger;

/**
 * Class monitoring the instruction resources allocated for a service
 * @author DERUELLE Jean
 */
public class ResourceMonitor {
    /** log4j logging*/
    private static Logger logger = Logger.getLogger(ResourceMonitor.class);
    /**the number of instructions read at this time*/
    private int currentInstructionCount=0;    
    /**the service*/
    private String service=null;     
    /**the access control context of the jvm with wich we will check the resource permission*/
    private java.security.AccessControlContext context=null;
    /** 
     * Creates a new instance of ResourceMonitor 
     * @param mainClass - the main class where is the resource monitor
     */
    public ResourceMonitor(String mainClass) {
        service=mainClass;
        SecurityManager securityManager=System.getSecurityManager();
        if (securityManager != null) 
            context = (java.security.AccessControlContext) securityManager.getSecurityContext();  
    }
    
    /**
     * This is called before a basic block is entered. 
     * @param instructionCount -the number of instructions executed in the basic block.      
     */
    public void countInstructions(int instructionCount) {
        currentInstructionCount +=instructionCount;                 
        try{
            gov.nist.security.permissions.InstructionResourcePermission instructionResourcePermission=new gov.nist.security.permissions.InstructionResourcePermission(Integer.toString(currentInstructionCount),"allowed");
            //System.out.println("Checking in your group policy file for the following RESOURCE PERMISSION : "+ instructionResourcePermission);
            context.checkPermission(instructionResourcePermission);                  
        }
        catch(Exception e){
            System.out.println("The service "+service+" has overstepped its instructions limits ");            
            System.out.println("The service "+service+" is exited");            
            System.exit(1); 
        }                                                             
    }
    
    /**
     *  Reinitializes the currentInstructionCount to zero
     */
    public void restartCounting(){
        currentInstructionCount=0;        
    }
}